the portrait of the Earth
This page represents the attempt to make the general portrait of our planet 25 MY in the future in view of a present condition and known tendencies of change of the planet. The review of geography, flora and fauna of continents and major islands is given.
|Antarctica and subantarctic islands|
|Islands of Atlantic ocean|
|Islands of Pacific ocean|
|Islands of Indian ocean|
In the Neocene, the continent of Europe still endures the
influence of the northward movement of Africa during the Cenozoic. During the
Neocene, this movement has completely closed off the Strait of Gibraltar, which
had previously served as a physical border between two continents. The consequences
of this were catastrophic. Most important of all was the complete drying out
of the Mediterranean Sea. At the northern end of Europe, the gradual raising
of the northern edge of lithospheric plates has caused a shallowing and regression
of the North Sea. The British isles joined to the continent, and the Baltic
Sea has turned to the Wenedian Lake - a freshwater reservoir gradually filling
with sediments brought to it by rivers.
In the Neocene, to the south of the Alps, between Africa and Europe, there is now a huge depression; during the age of man it had been the bottom of the Mediterranean Sea. Layers of the salts once dissolved in water have formed here, and a significant extent of the Mediterranean depression is completely unsuitable for life. Here, day time heat is replaced with the chill of night, and lack of fresh water makes plant and animal life virtually impossible. In the centre of this hollow, separate hyper-saline lakes are doted across the landscape, and closer to the Alps, there are extensive salt swamps filling from time to time with rains washed down through the rivers flowing down from the Alps. The edges of the Mediterranean hollow are comprised of semidesert with separate oases receiving water from the rivers. Practically all rivers flowing down from the southern slopes of the Alps form deltas and turn into ephemeral swamps and lakes which more often than not dry up in the summer and the autumn. In the Mediterranean hollow, there are also the "oases" formed of the tops of mountains that were originally islands in the Mediterranean sea. They exist due to condensation of atmospheric moisture on stones because of the significant daily temperature drops.
To the north of the mountain ranges of the Alps, climatic conditions are completely different The climate of Northern Europe is determined substantially by the North Atlantic and Arctic Oceans. The northern coast of Europe is covered in extensive plains made up of loose river sediments. In fact, all rivers flow to the north, forming extensive deltas and marshes submitting to the tidal influence of the ocean.
The movement of Africa to the north and its slow collision against Europe became the reason for the increase of tectonic activity in the Alps and the other mountain systems. In Southern Europe, there are some active volcanoes erupting periodically. Peaks in the Alps are covered with glaciers whose area is less than what it was during the age of man because of the warmer climate.
In fact, all of the mountain lakes of the Alps that existed during the age of man were filled with river sediments over the course of several millenia and had turned to marshes, replaced then by meadows and forests. The ice age at the boundary of the Holocene and Neocene epochs had left behind some other lakes which also had disappeared during the early Neocene. In the Alpine valleys, there are still a few large lakes gradually filling with river sediments.
The mountain ranges of the Balkans and Caucasus differ in the large number of caves that in some cases form extensive cave systems.
Scandinavia is yet another place in Europe where it is possible to see glaciers. They are located in the mountains in the northern part of Scandinavia and from there, short rivers full of rapids flow down into Wenedian Lake. Many other rivers in the northeast of Europe also run into this lake. From Wenedian Lake, water flows to the Atlantic as a wide boggy stream vaguely similar to the Everglades (Florida) of the age of man. The central and northeastern portions of Europe are places where a continental climate dominates and the change of seasons is expressed most dramatically. Summer is warm here, but winters are snowy and bitterly cold.
Map of Fourseas.
At the north the Three-Rivers-Land is visible; at the southwest there is a Mediterranean hollow with “oases” and hyperhaline lakes. Picture by Carlos Pizcueta (Electreel )
Along the border of Europe and Asia, there is one huge reservoir
that is the spiritual successor to the Mediterranean: Fourseas. It was formed
after the northern part of the Caspian Depression was flooded, uniting the Black,
Azov, Caspian and Aral seas. During the ice age, 5 million years after extinction
of mankind, these seas had dried up, but later reappeared. Because of orogenic
processes the straits of the Bosporus and Dardanelles have closed, and Fourseas
has no connection with the oceans. Its level had risen, and in the Neocene the
Crimean peninsula has become an island. The eastern part of Fourseas is shallower;
near the coast there is a vast region of shallows and temporarily existing islands.
The rivers of Central Asia run into Fourseas, forming large deltas, rich in
reed beds. The western part of Fourseas is deeper; it gets warm much slower
in summer, but also cools down much slower in winter. The Caucasus in the Neocene
has become a large mountainous peninsula jutting into Fourseas from the south.
Although the northeastern coasts of Fourseas may get cold enough to freeze over, the western and southern coasts are much warmer , and so never freeze. Fourseas forms the greatest influence on the climate of southeastern Europe, making it milder and more humid. The area along the northern coast of Fourseas is called Three-Rivers-Land: the rivers from the lowland parts of Eastern Europe flow in ancient channels of the lower reaches of the Volga, Don and Dnieper rivers.
Although they are old and eroded to a great degree, the Ural mountains serve as a natural boundary of Europe in the east. During the most recent ice age, the Urals have been substantially ground off by glaciers and smoothed over.
The climate of the coasts of Europe is determined by the influence of a cold current called the Antigulf Stream, flowing from the Arctic Ocean to the north. Because of it, the Gulf Stream has strongly deviated to the west and the climate at the west coast of Europe became cooler and much more humid. At night, large coastal fogs and plentiful dew are the norm.
The climate of the Neocene in general is damper and warmer
than in the age of man, and in the southeast of Europe, in the Caspian Depression,
Fourseas was formed - a huge lake with brackish water. Around this reservoir,
the conditions became more favorable for the growth of plants - the climate
is considerably more equable and humid. Plants from the forests surrounding
Fourseas to the south and west have obvious features of a tropical rainforest
flora. They have wide leaves with the extended tips forming guttation droplets.
But true tropical species have not penetrated to the north: their advance has
been halted by the savannas of the Sahara, the Alps and mountains of Asia Minor,
and also by the Mediterranean depression, whose marshes and saline soils are
undoubtedly adverse for the growth of tropical plants. Therefore, the flora
of the northern subtropics has formed from the stock of local species which
had independently developed adaptations to life in a warm climate. A large number
of endemic plant species live on the Caucasian peninsula which juts out into
Fourseas: the phenomenon of altitudinal zonation, and also the presence of isolated
habitats makes the area a species factory. There are much fewer endemics inhabiting
Crimea Island, which is located very close to continental Europe.
Forests, especially on the Caucasian peninsula and in the Balkans, are rather young and multileveled (some species of European flora have only "just evolved" into trees), therefore forest canopy is "loose", made up of trees of various height. It allows a large amount of sunlight to penetrate into the underbrush where the flora of shade-loving and moisture loving plants (eg. mosses and ferns) has developed. In the middle level of the forest lianas prosper - perennial descendants of ivy and grapes, reaching enormous sizes. Descendants of ivy became hardy evergreen lianas with strong leathery leaves; they have adapted to cold climates farther to the north, and now live in all parts of Western Europe. To the north, they have much smaller leaves, and some species have dissected leaves. Southern descendants of ivy have evolved into evergreen ligneous lianas with thick trunks, rough bark, and roots adapted for tree-climbing. Their trunks frequently creep on the ground, bounding with roots of trees and making some parts of forest almost impassable where they grow. Descendants of grapes have evolved into deciduous plants with large soft leaves, allowing them to go into a state of partial hibernation in the winter. They prefer humid areas near to waterways. Epiphytic plants are present as various ferns and small angiosperms, which are characteristic for the subtropical forests of Europe (especially in the southeast, on the coast of Fourseas). Growing on them are "epiphytic baskets" of mosses and lichens, forming meter-long "beards" like the Usnea lichen in the present day.
On the ground, orchids grow - larger descendants of species of today, these are perennial bulb plants with large single flowers (the single flower of an orchid represents the reduced cluster). Also on trunks and plank-buttress roots of large trees, at a height of up to two meters above the ground, lichens and ferns are plentiful.
The flora is particularly luxurious close to the coast of Fourseas. As one travels deeper into Europe, features of the subtropical vegetation gradually fade, and the flora of Central Europe (to the north of the Alps) is more similar to the one that existed in the age of man. The European forests are largely made up of oak, beech and chestnut; to the south the plane tree is added to them. To the north, small-leaved forests of birch and poplars grow. Wetland habitats near lakes and rivers are clothed with willow trees of various species. Although in subtropical forests maple descendants are dominant, to the north, maple grows only as one of many species of tree in the deciduous forests.
A unique complex of vegetation has developed on the coast of Western Europe. Here, along the coast, the extensive littoral strip stretches, being replaced further inland with brackish marshes. Significant areas of wetlands are occupied by halicole grasses. In addition, a portion of land from Wenedian Lake through former the Skagerak and Kattegat passages resembling the Everglades of Florida exists - a wide, shallow and boggy river through which the surplus of water is removed from the lake. On the littoral area of the North Sea coast line, the landscape is dynamic and very changeable, and on the coastal strip small islands made by inflow of water appear regularly. The treelike vegetation at such areas is present as separate thickets of moisture loving species, like the willow tree. Other trees grow only further inland, where the ground is drier and the influence of the salty sea is not felt as strongly. Because of the cold Antigulf Stream, summertime on the coast is cool and damp, and fogs come off from the sea.
The vegetation of the Alps expresses the phenomenon of altitudinal zonation. Higher in the mountains, deciduous forests are replaced with mixed ones, and even higher up coniferous forests are widespread. On the tops of mountains, alpine meadows dominate, and right on the doorstep of the glaciers the vegetation is similar to the tundra of the far north.
To the south of the Alps, the climate is completely different - here, the hot and dry "breath" of Northern Africa and the Mediterranean depression is felt. Here, plants are forced to struggle for survival on the narrow strip of semideserts between the Alps and the saline soils of the Mediterranean. These regions receive significant amounts of salt dust with the southern wind and only some rain from clouds moving south from the North Sea that manage to pass through the Alps.
The westernmost part of Europe (the isthmus of Gibralter) and areas near the Mediterranean depression (to the south of the Alps) are covered with dry forests and thickets of bushes (maquis). Laurels, treelike and bushy myrtles, and drought-resistant species of oaks and olive trees dominate here. Closer to the Mediterranean depression, light forest and maquis are replaced by semidesert, with deposits of saline soils left by the receding sea. Only sickly, woody vegetation grows here, but the halicole grasses, which do not form a continuous grassy cover, appear here and dominate in some places. Also, on the edges of the Mediterranean depression, succulent plants, including descendants of introduced cactuses, are characteristic. In the spring, in the area to the south of the Alps, a period of short-term, but plentiful moistening of the ground occurs, when snow caps thaw on the tops of mountains and the streams flow down to semi arid areas and form temporary reservoirs. At this time, rapid growth of tuberous and bulbous plants begins; for most of the year they stay under ground in a dormant state. They only have a few weeks to flower, produce seeds, and to save up a surplus of nutrients, and the annual part of the plant dies off.
On the Atlantic coast of Europe, at the same latitude of the Gibraltar isthmus and the Iberian Peninsula the dry climate is contrasted with the plentiful morning fogs, and grassy plants have developed adaptations for catching atmospheric moisture.
The numerous islands of the Mediterranean have turned to "oases," separated from each other by salt deserts and receive rain which is condensed at the tops of mountains. Here, woody vegetation grows, under which a world of mosses and ferns prospers. Plants soak up water like a sponge, and thus support their own existence, being similar in this respect to a tropical forest.
The north of Europe (from Scandinavia up to the Urals) is located in the zone of a clearly expressed, seasonal climate with cold winters, with polar days and polar nights. Winters are snowy and usually frosty, therefore the prevailing type of vegetation is made up of coniferous forests with small areas of broad-leaved forests. In the Far North, the permafrost has gradually thawed, enabling the growth of grasses. The short-term period of the existence of marshy tundra had been followed by an epoch where northern meadows flourished, dominated by graminoids and sedges. The general climatic warming in the Neocene in northern Europe is counteracted by the existence of the Antigulf Stream, which appeared after the Bering Strait closed once the Arctic Ocean became a virtually landlocked "polar lake." Nevertheless, there is enough summer heat here for plentiful growth of grassy plants. The characteristic tundra vegetation, including undersized humifuse trees and evergreen under-shrubs, has retreated to wetlands and mountain tops.
To the south of the Northern polar belt, the coniferous and mixed forests extend, replaced gradually by oak groves further to the south. For the forest zone of eastern Europe peat bogs are typical, especially in the north. As one travels south, bogs become rarer, and the forest vegetation gradually moves to river valleys, and beyond the waterways grasslands and steppe vegetation proliferate.
On the northern coast of Fourseas the typical grassland vegetation is formed of graminoids and other grassy plants with small areas of trees and bushes in the river valleys. Glaciers have left the valleys formed in the lower reaches of three major rivers of the region - Volga, Dnieper and Don - largely untouched, and areas of steppes along the northern coast of Fourseas are named Three-Rivers-Land because of it. The belt of steppes stretches along the coast of Fourseas to the east, deep into Central Asia. In river valleys and near cutoff meanders, separate islets of woodland vegetation have sprouted, and in river deltas thickets of trees and bushes able to endure flooding flourish. The climate in these areas is highly seasonal: cool, rainy winters and dry, warm summers. The salinity of the water in Fourseas is low, and it permits aquatic plants to grow profusely. Thus, the coasts of Fourseas are, in places, are overgrown with rich reed beds, and in deeper waters, perennial aquatic grasses prosper.
The fauna of Europe represents a part of the Holarctic realm.
The low percentage of endemic animals groups is characteristic of this realm.
Western Europe is joined to Africa with the help of the Isthmus of Gibraltar,
and thus circumstance has prompted the appearing of some African groups of animals
in Western Europe: including large descendants of hyraxes, massive representatives
of viverrids, and also monkeys and ostriches.
Only a few groups of mammals are endemic to Europe. They include rabbit burrowers, a family of burrowing lagomorphs that evolved after the human extinction. The dwarf otterseal, the last species of pinniped on Earth, an inhabitant of Wenedian Lake, is one of more unique endemics of Europe. One more group of European endemics are large predators descended from hedgehogs. Large carnivorous hedgehogs look more like the long-extinct creodonts than the more advanced true carnivores; they represent a branch of relicts from an early Neocene radiation of small mammals. The active medium-sized predator niche is occupied across the continent by the European spinywolf, a large dog-sized animal. In the maquis of the south, its smaller relative lives; the hedgejackal, a scavenger and small animal hunter. One more species of large hedgehog is the southern European chagrin, a large omnivorous species leaning toward carnivory from the forests of Southern Europe (the Balkans, and the coasts of Fourseas). It is a general analogue of badger, but it doesn't build dens and does not hibernate.
Harelopes are the group most characteristic for the Holarctic; these are small and medium-sized herbivorous mammals, ecological analogues of deer and small antelopes, but descended from hares of the Holocene epoch. In areas where the continental climate dominates, harelopes share their habitats with titanolagids, one more group of hare descendants that evolved into large herbivores. Alongside such specialized forms of herbivores, the true hares and rabbits, and also numerous rodents (squirrels, mice and so on) live in Europe. Among the rodents a group of carnivorous descendants of dormice have evolved, competing with small carnivores.
To the south of the Alps, in the maquis at the edges of the Mediterranean depression, whistlehorns live; these mammals are representatives of a group of ungulates of Asian ancestry, descendants of bovids.
In the "oases" of the Mediterranean depression, mammals are a great rarity. No large forms live here and there are only local representatives of rodents and insectivores. Through convergent evolution, many species of rodents developed independently from each other the adaptations for desert living, allowing them to make metabolic water, while tiny species of insectivores simply lick dew or receive their moisture from prey. Moreover, tops of mountains of these "oases" are covered with forest or bush-lands, serve as "rain magnets," and small reservoirs, more often than not in karstic caves protected from the sun's heat, are occasionally formed here. Rodents and insectivores of the "oases" are not the most numerous small animals, being largely outcompeted by a variety to birds and reptiles.
In Europe there are large representatives of the trunk boars, another newly evolved group of Neocene herbivores.Externally resembling elephants and tapirs, they eat mainly soft vegetative food e.g leaves and grasses, and also roots, tubers and fruits. Compared to harelopes and titanolagids, they prefer more humid habitats, although some species live in the dry maquis.
The family of porcippulas is a result of an attempt of pigs to produce a specialized, running grazer, adapted to life in open areas. Porcippulas are related to trunk boars and inhabit the steppes of Thee-Rivers-Land and open areas to the east of Fourseas. Some species even penetrate into taiga and the foothills of Central Asian mountain ranges. Porcippulas in general are natives of temperate and warm-temperate areas of the Holarctic, and, more precisely, the Palearctic.
The true pigs also live in Europe, but their number is far less than in the Holocene
Endemic families of predators are not present in Europe. In comparison with the age of man, the set of families has almost not changed, except for the complete extinction of bears. Small and medium-sized predators include mustelids and small cats (descendants of feral domestic cats). These are mainly forest predators. Large predators of Europe include heavily-built mustelids (in the north of Europe, cold-temperate and polar areas), cats and canids (most parts of Europe), and also large viverrids (the west and the south of Europe).The presence of viverrids in the European fauna is a result of the land connection between Africa and Europe - European viverrids are closely related to North African species. There are also viverrids of Asian origin (Zibetonyx) inhabits the steppes of southeastern Europe, the Three-Rivers-Land. Descendants of the North American raccoon, introduced in human epoch has partly replaced ursids in Neocene Europe; they are omnivores with a bias toward herbivory. The largest species among them is a bearaccoon, the false panda. In addition some small arboreal species live in forests of Central Europe and in the European subtropics along the coast of Fourseas. These species are less derived from their ancestors than the bearaccoons, but go down on the ground less often than modern raccoons.
The birds of Europe express a smaller degree of endemism compared to the mammals; it is connected to their great migrations and the absence of natural barriers that would impede it. A family of running rallids includes the ostrich rail in the steppes of Three-Rivers-Land, and is common across Europe and Asia.
The influence of the Antigulf Stream had resulted in the settling of some northern forms to the south. On the Atlantic coast of Europe, large flightless loons, birds of Arctic origin, are characteristic.
The land bridge between Eurasia and Africa promoted the appearing of ostriches in Western Europe. Ostriches has also spread to the edges of the Mediterranean depression, and separate dwarf species of ostrich inhabit some of the "oases." Some species of birds have adapted to life amongst the salt flats and saline swamps. In the salt swamps, ground-dwelling flightless flamingos live.
Otherwise, the endemism of European birds is expressed at the genus level. The fauna of forest birds at the family level is almost the same as it was in the age of man. A number of groups of birds characteristic of the Holocene died out from human actions: these include large falcons, eagles, griffon vultures, and also cranes. Modern representatives of large flesh-eating birds include various species of eagleravens of the Carnocorvidae family. This family of birds is endemic to the Holarctic and prefers the cold and temperate areas of Eurasia and North America. Among the carnocorvids there are species living on the coast of the Arctic Ocean, in forests of the temperate zone of Eurasia, and also in the steppes of Three-Rivers-Land. The genus of predatory and scavenging birds Tanatopterus has settled in all parts of the mountain belts across Eurasia, from the east to west, forming a continuous chain of species indistinctly separated from each other - the next species are connected by intermediate forms. Species from warmer and dryer areas have naked skin on the front part of the head and neck, unlike the inhabitants of the Alps and Himalayas.
Galliforme birds of Europe represent various descendants of the common partridge, pheasants and quails. European quails have moved to some islands of the Atlantic, having evolved into a number of endemic species there. Tetraornids are extremely cold-resistant birds inhabiting the northern and mountain areas of Europe. They are mainly descendants of white grouse and hazel grouse.
Among nightjars, there are is a large species from the steppes of the southeast of Europe - the merlette, a short-billed, eagle-sized nightjar that hunts birds and bats by night.
The reptiles of Europe have remained approximately at the same level as in the age of man in the diversity of families. The majority of species of reptiles have large ranges; to the north their variety is greatly reduced, and only a few species can withstand the polar regions. The variety of reptiles is much greater in the southern areas of Europe: on the Balkans and Apennines and on the edges of the Mediterranean depression. In the south and west the herpetofauna of Europe is has obvious Western Asian and African influences. The turtles of Europe are not too numerous. The southern coasts of Fourseas are inhabited by several species of turtle, and separate species live in Central and Western Europe. Wenedian Lake is the northern border of turtle populations in Europe. The variety of tortoises is greatest at the borders of Mediterranean depressionTurtles of Europe are not too various. Southern coasts of Fourseas are inhabited by some species of turtles, and separate species live in Central and Western Europe. Wenedian Lake is the northern border of turtle area. The variety of tortoises is great at the borders of Mediterranean lowland. In the "oases" one large species of tortoise and several smaller ones live. Also, tortoises live in the subtropical forests of the Balkans.
In large areas of Europe, representatives of the true lizard family (Lacertidae) are widespread; in the valleys of the Alps there are several endemic species. At the southern end of Europe, representatives of the blind worm family also live; one very large species inhabits the subtropical forests of the Balkans. In the maquis south of the Alps, representatives of other families live - geckos, skinks and agamids. These reptiles have produced many endemic species in the "oases" of the Mediterranean depression, and one species of skink has adapted to life in hyper-saline lakes. The top predators of the "oases" are lizards and snakes: the animals that are most able to grow to large sizes, to live for a long time, and needing little food in order to do it. This allows them to form large populations on poor food resources of the "oases". Agamids and geckos live in the subtropical forests on the southern and western coasts of Fourseas, and some species of agamids live in the steppes of Three-Rivers-Land. Monitor lizards live only in the westernmost parts of Europe, and are doubtless immigrants from Africa.
Among the snakes, there is an endemic family of aquatic natricids, represented by the atargatis - a completely aquatic, nonvenomous snake from Fourseas. Other snakes include representatives of the adder and colubrid families. On the Isthmus of Gibraltar, there are representatives of the elapid snakes of African origin.
Amphibians of Europe include only caudates and anurans. Some species of caudate amphibians living in temperate areas of Eastern Europe reach great sizes, and their close relatives are huge species from the swamps of Western Siberia. The majority of caudate amphibians from Europe are small - these are newts and salamanders, more speciose in the Neocene than in the age of man. Representatives of the tailless amphibians include true frogs, toads and fire-bellied toads. Among fire-bellied toads, there are some species that have very potent poison for defense. Relic species of toads live in some "oases" of the Mediterranean depression, having evolved into tiny inhabitants of karstic clefts and leaf litter. In the caves of the Alps, a few endemic species exist. In the Far North of Europe, only a few newts, toads and true frogs are able to withstand the cold temperatures.
The variety of fishes of the inland waterways of Europe at the family level also does not differ from those in the human epoch. The number and variety of sturgeons was reduced considerably - they survived only in Fourseas, but they have evolved into one of the largest species of European fishes. In freshwater, there are representatives of cyprinid fishes and true loaches, as well as gobies, perches and pikes. Among the largest fishes of Europe are catfishes; among them, there is one predatory species able to drag a terrestrial animal weighing up to 40 kg under water. The presence of eleotrid fishes, descendants of the Amur sleeper (Perccottus glenii) introduced by people, in the fresh waters of Europe is an ever present reminder of the hand of man. In the Neocene, eels have moved to freshwater permanately in Europe; they managed to breed there due to their new adaptations toward vivipary.
Among the anadrom fishes of Europe, croakers inhabit most rivers in Western Europe. Blennies and eels, adapted to changing salinity and temporary life on land, live in littoral swamps on the coast of the North Sea. In many large rivers, flounders live, growing fat in fresh water and spawning in the sea.
The rich ichthyofauna of the Mediterranean Sea has died out with the collapse of the sea, but at the northern edges of the Mediterranean depression there are some relic salt lakes whose existence are supported rivers flowing down from the Alps. The true marine fishes - the last representatives of the Mediterranean fauna (dwarf croakers, gobies and blennies) - live here.
A few species of fishes live in caves of the Balkan and in "oases" of the Mediterranean depression.
Among the invertebrates of Europe, the evolution of scuds in Fourseas is most remarkable: here, these crustaceans express a perfect example of adaptive radiation, having evolved into a menagerie of forms - from tiny planktonic organisms up to active predators. Also in Fourseas, some species of fully aquatic, pelagic insects permanately living far from the shore have evolved.
Franz Jozef Land, Arctic Ocean
Atlantic coast of Southern Europe
Salt marshes of Mediterranean lowland
Brackish sea-like lake in South-Eastern Europe (not translated, Russian version only!)
South-Eastern Europe, northern coast of Fourseas (not translated, Russian version only!)
Steppes of Southern Europe (not translated, Russian version only!)
Steppes of Southern Europe (subterranean animals) (not translated, Russian version only!)
Wenedian Lake (northwest of Europe) - fishes and crustaceans (not translated, Russian version only!)
|Some minutes of sunlight||
Edge of Cyprus mountain ridge in Mediterranean hollow; inhabitants of desert and subterranean reservoir. (not translated, Russian version only!)
South-western Europe, edge of Mediterranean hollow.
(written by Bhut) (not translated, Russian version only!)
In the Neocene, Asia is still the largest continent on Earth.
The movement of Africa to the north has a much smaller influence to the geography
of Asia in comparison with Europe. The African lithosperic plate, because of
its movement to the north, pushes the Arabian plate into the Eurasian one and
interferes with Red Sea rift expansion. As a result of it, there is a lot of
tectonic activity in the areas of Arabia and the Near East. The Red Sea has
lost its connection to the Indian Ocean and has turned into a deep hollow, at
the bottom of which the salts once dissolved in seawater have accumulated. Not
one river runs into it, and it has dried up over the course of countless centuries.
The Persian Gulf does not exist in the Neocene, and in its place, a young and still rather low mountain range has risen. The great deposits of oil in the region were exhausted in the human epoch, but tectonic activity has raised deep rock layers containing residual deposits of oil on the surface, and in some places near the Persian Ridge there are natural asphalt lakes similar to the La Brea tar pits of California.
The massive Indo-Australian lithosperic plate has continued its movement to the northeast, putting pressure on the Chinese lithosperic plate. The result is the continuation of the growth of the Himalayas and massive volcanic activity in the Greater Sundas island chain. Large islands have gradually merged into a long and narrow land strip - the Jakarta Coast.
The continental part of Asia is made of four lithosperic plates: Eurasian (stretching to the east beyond Ural), Chinese (including the Far East and Southeast Asia), Indian (Hindustan) and North American (Northeast Asia: a part of Eastern Siberia, Kamchatka and Chukotka). The melting of most of the world's glaciers after the Holocene-Neocene boundary has caused a raising of the northern edge of the Eurasian plate that has resulted in rivers changing their course and the occurrence of extensive swamps on the plains of Western Siberia, right up to the Ural mountains. As a result of the Atlantic Ocean spreading and the movement of the North American plate to the west, the tectonic activity in Northeastern Asia has amplified, and in place of the Bering Strait, the Beringean isthmus was formed. Northeastern Asia in the Neocene is still a mountainous area, separated from the lowlands of Western Siberia by an extensive plateau.
The Far East in the Neocene is also made up of hilly terrain; the main area of tectonic activity here is at the coastal areas, the place where the Pacific lithosperic plate is moving under the edge of the Chinese plate. The result of this is the volcanic activity on the islands along the Pacific coast of Asia - from Japan north to Kamchatka. The Kurile Islands in the Neocene have considerably increased their area and have turned into the Big Kuriles. They have almost entirely separated the Sea of Okhotsk from the Pacific Ocean - its connection to the ocean is supported only by narrow passages between the islands of the Big Kuriles and Japan. The Philippine plate has drifted much closer to the continent, and a land bridge between the Philippine archipelago and continental Asia, with the help of a chain of newly formed volcanic islands, has appeared.
In Central Asia in the Neocene, the opening of the Baikal rift zone is the most evident change in geography. It has resulted in expansion of Lake Baikal - the deepest and oldest lake on the planet.
Asia is a vast landmass, and the interior is dominated by a continental climate, despite the general climatic warming in the Neocene. A significant part of Asia to the north of the Himalayas and the mountain ranges of the Near East clearly express a highly seasonal climate with cold, snowy winters and hot, baking summers. Lake Baikal softens the climate in its vicinities slightly. On the coast of the Pacific Ocean the climate is much milder than it is in the centre of the continent, but rains and hurricanes often occur here. As a result, on the coast, especially in areas of a subtropical climate, floods are frequent. Southeast Asia has a monsoonal climate, and the southern coast of Asia (Jakarta Coast and the islands to the east of it) is basking in an equatorial climate - with an abundance of rain and year round heat and humidity.
Western Siberia is comprised of an extensive boggy plain, where in the river valleys, a circuit of lakes and cutoff meanders is formed. In due course, river channels change direction sharply, forming new sedimentary deposits and destroying already existing ones. In Eastern Siberia, the direction of rivers is determined mainly by features of the landscape made of hard rocks. The rivers of Western Siberia reach the seas of the Arctic Ocean basin, separating into a number of branches, while the Eastern Siberian rivers frequently flow in narrow gorges and sometimes reach the ocean as waterfalls. In mountainous regions, there are a large number of lakes formed by the changing river channels. After the glaciers receded in these areas, they left behind oligotrophic lakes with clear water and rather poor aquatic life, but during the subsequent millenia they have disappeared almost completely: having filled in with river sediments, they turned to bogs and have since overgrown with forests. From a backdrop of short-term existing lakes of glacial origin, Lake Baikal looks like the greatest exception. Over millions of years of existence, this reservoir's depth has decreased very little, but the width and length have increased dramatically.
On the coast of the Pacific Ocean (Kamchatka, the Big Kuriles, and Japan) in mountain valleys, a number of geothermal springs exist and there are even small lakes, warmed by underground heat.
The coast of South and Southeast Asia, and also the islands of Indonesia, are made of rather fragile rocks, and rivers in these areas twist on flat plains, forming circuits of channels and cutoff meanders. In the mountainous areas of Indochina, rivers flow in mountain valleys where they have washed out deep gorges over millions of years. In mountain valleys there are lakes, and the age of some of them are millions of years old.
Sea currents mainly influence the climate of the Pacific coast of Asia. Warm southern currents considerably soften the climate of the coastal areas of the continent, and promote the settling of warmth-loving, subtropical species to the north. The closure of the Bering Strait and the significant temperature difference between the Arctic Ocean and the northern edge of the Pacific Ocean results in high northern winds carrying cold air to Beringia, and also a significant amount of snow in winter.
The warming that followed the Holocene-Neocene boundary had
caused the thawing of permafrost in the north of Eurasia. It actually has resulted
in the disappearance of tundras and their replacement with floral communities
resembling steppes and based on graminoids and sedges. The same has happened
in Europe, with the tundra vegetation remaining only in the mountains, near
Increasing rainfall has resulted in the replacement of the northern subpolar graminoid and sedge communities by elfine woods of hardy deciduous and coniferous tree species which, further south, form the extensive zone of northern forests stretching from Western Siberia through Beringia to the east of North America. Compared to the taiga forest of the Holocene epoch, the northern forests of the Neocene differ in their greater diversity of plants and do not form a "monotonous" forest stand because of the presence of large herbivorous mammals in the fauna of Northern Asia, which make wide, migratory pathways in the coniferous forests, becoming overgrown with grass, bushes and deciduous trees that promote the occurrence of various habitats and enrichment of the woodland flora.
The swamps of Western Siberia represent a place of plentiful growth and the remarkable development of marsh flora. Short, but hot and humid summers promoted the evolution of large, fast-growing grassy plants with perennial tubers and rhizomes. Some monocots from sedge communities in areas of warmer summers and an abundance of moisture have developed into undersized, treelike forms resembling Pandanus and Dracaena from the tropics, but these "trees" are deciduous. Also in the swamps and rivers of Western Siberia, perennial aquatic and amphibious grasses are widespread.
Central Asia is located in an area of a strong continental climate, and only around Lake Baikal are its features softened a little. To the south of the zone of coniferous and mixed forests, the steppe vegetation stretches, passing an area of semi-deserts to the south. The warming and humidifying of climatic conditions in the Neocene has resulted in milder conditions in the deserts of Central Asia in comparison with the human epoch. The rivers from mountain ranges in Central Asia water the landscape and promote the growth of extensive thickets of bushes and low-growing deciduous trees. Due to regeneration with the help of root shoots which new branches sprout from, these plants can endure sand storms and other natural disasters, quickly being restored after them.
The mountain ranges stretching across the entire continent that fade into the mountains of Europe show a perfect example of altitudinal zonation. On the southern slopes of mountains, plants from the subtropics and tropics of Southern Asia manage to survive, replaced by immigrants from the north closer to the summits. The numerous mountain valleys are isolated from each other, and ranges separated by valleys are habitats of various endemic plant species, mainly grasses.
In the Far East, due to warm ocean currents, deciduous forests of the subtropical variety grow further north than is typical. Characteristic plants of such forests belong to the Araliaceae family, whose species vary from perennial grasses up to small fast-growing trees. The forests of the Far East are formed by various representatives of mainly southern families, including various species of walnut and chestnut trees. Species of oaks and maples, distinguished by large, fancifully shaped leaves are also common. The understory is made up of large, broadleaved grasses and small bushes. In Japan the "tree of death" lives - it is one of the largest species of poisonous plants on Earth. Species of the sumac family closely related to this tree are widespread in forests across the Far East and range from the size of bushes up to small trees. In the mountains, rhododendrons are widespread, varying in size from low bushes up to small trees. The forests of Japan, the Big Kurils and the southern coast of the Sea of Okhotsk are the northern limit of the distribution of epiphytic plants. Communities of epiphytes here are made up exclusively of medium-sized ferns and mosses, but, to the south, orchids and other typical epiphytes also exist, and ferns become far more diverse. Various species of bamboo, from small plants only 2 meters in height, up to very large ones about 10 meters tall, grow here.
Western Asia and the areas around the Mediterranean depression are in a remarkably dry climate with significant daily temperature shifts. Various succulent plants and also bulb ephemeroids vegetating for some weeks in the year live here. The woody vegetation includes oaks with creeping trunks, and on the island "oases" of the Mediterranean depression, dwarf drought-resistant oaks grow. For the edges of the Mediterranean depression and Western Asia, various descendants of prickly pear cactuses introduced by people during the age of man are characteristic.
Eastern Asia, in the area of subtropical and tropical climates, is a the place where humid winds from the ocean meet a mountain barrier and pushes up moisture that falls as rain. The floodplains are made of fine and easily washed away sediments, and the rivers frequently change their course, overflowing and flooding extensive areas. The woodland vegetation of the plains is able to survive these inundations. In the mountains, where there is no danger of flooding, heat-loving citrus trees and representatives of the Theaceae family, and also ficuses and palm trees form large forests.
Various ficuses and legumes are the dominant woodland flora of southern Asia. These plants form a wide spectrum of life-forms - from grassy plants and bushes up to lianas and large trees. In addition, in these forests, palm trees and treelike species of various plant families grow: spurges, sumacs, Vitaceae, Asteraceae etc. Grassy plants are present by plants of the following families: gingers, aroids, orchids, begonias and many others. Among begonias, in the Neocene, fast-growing begonia trees have evolved - it was a successful attempt to develop a new life-form. In mountainous areas, bamboos of various species grow up to altitudes where snow falls very heavily in winter. In lowland forests, bamboo species expand in areas of damaged forest, but it is gradually replaced by tall tree vegetation.
Along the coast of Indian Ocean, in the area of a tropical and equatorial climate, mangrove forests grow, and in river mouths there are thickets of Pandanus trees. Among aquatic plants, lotus is common and is fairly typical (probably due to cultivating in the human epoch), and water lilies are widespread and frequently reach a great size.
The equatorial climate of the forests of the Jakarta Coast and the islands of Indonesia favours the formation of true tropical rainforests. At the level of botanical families, the variety of flora resembles the condition in the Holocene, but a significant amount of species have died out at the border of the Holocene and Neocene or later, replaced by new plants settling in restored forests. Characteristic plants of tropical forests include giant grasses, and descendants of the banana tree cultivated in the human epoch. Among grassy plants, the richest in variety include gingers and aroids, among which there are numerous amphibious and aquatic grasses, and also tuber grasses. One more characteristic family of plants of south and southeast Asia is the Nepenthaceae family of insect-eating plants with specialized pitcher leaves. Among them there are medium-sized grassy plants, epiphytes, and large lianas.
The fauna of Asia belongs to two zoogeographic realms: the
Holarctic and the Oriental. Animals practically do not mix between these realms
across almost all of Asia from the west to east due to the presence of the mountain
ranges separating the continent lengthwise. Only in the Far East is there a
mixture of fauna and penetration of northern species to the south, and southern
ones to the north takes place. Inhabitants of the mountains in Central Asia
belong mainly to Holarctic families, but there are some species of southern
To the north of the mountains of Central Asia, the characteristic complex of fauna of the Holarctic realm is present. Various descendants of pigs are typical representatives of the mammal fauna. Porcippulas living in steppes and light forests along the southern edge of the forest zone are larger than the species from the European steppes. In addition, the largest species of trunk boar, the Siberian shurga, also lives here. The most atypical group of pigs is the small family of predatory pigs whose representatives are similar to the fossil entelodonts. They are scavengers and unspecialized predators in steppes and light forests of Central Asia; one species lives in forests in the Far East and has settled far to the south, up to northern borders of the Oriental realm. For the Asian part of the Holarctic, titanolagids are typical: the obda, the largest species of this group, lives here. In the Far North, the umingmak lives; it is the only species of titanolagids that have settled in the New World using Beringia. Also, harelopes are typical for the wooded areas of Asia; they are larger than varieties from Europe and Africa. The entire complex of small species of harelopes lives in the forests of the Far East and penetrates into the Japanese archipelago. Also, in Asia, typical lagomorphs live - hares, rabbits and pikas.
Bovids in the Holarctic are present as uncommon, specialized species like Saigochenia and the bald rambull from Central Asia. Large deer of heavy builds, the descendants of barking deer are species with a southern origin in the fauna of the Far East. Bulldeer from China and shishigami from Japan belong to this group.
Predators of the Asian Holarctic are mainly felines, mustelids and canids. Among cats, there are large forms descended from domestic and subsequently feral cats of the human epoch. The heavy-built species, the Siberian sabertooth, a descendant of the lynx, is the alpha-predator among them. Canids are present as various descendants of red foxes and arctic foxes. Some of them occupy the ecological niche of the wolf and hunt large herbivores. For the Asian part of the Holarctic a small family of bear-like dogs, the descendants of the raccoon dog, is unique. Separated from the rest of the family, zibetonyx, a running species of viverrid, lives on the steppes near Fourseas. Among mustelids, a large variety of body types is apparent: small arboreal and ground forms, large ground predators (berl) and heavily-built omnivorous species (arctomeles). Viverrids are atypical inhabitants of the Holarctic; they are diverse only on the border of the Oriental realm. In the Far East, there are several species of omnivorous arboreal viverrids, and to the south, in the swamps of China, there are semi-aquatic, omnivorous and piscivorous forms of viverrids, and also specialized species that feed on crustaceans and molluscs. Primates are only a small part of the Holarctic fauna, as it is the northern limit of their range. Large species of the separate parapongid family, the false-apes, are representatives of primates here. In addition to forest species, parapongids have adapted wonderfully to terrestrial life in cold, montane climates. In Japan, the kappa lives - it is a specialized, semi-aquatic species of macaque.
Lake Baikal is the habitat of a relic cetacean species, the Baikal hard-beaked dolphin. The second relic species of Neocene cetaceans lives in lakes in China; it is a dwarf species of porpoise, the descendant of the finless porpoise.
Rodents of the Asian sector of the Holarctic realm include various sciurids (squirrels, susliks, marmots), mice and hamsters. In Asia Minor, on the coast of Fourseas, in the Balkan region and in areas surrounding the Mediterranean depression, porcupines live. In arid areas, jerboas are numerous. Insectivores, as well as in the age of man, include hedgehogs, moles and shrews. In the Far East, there are members of an aquatic shrew family - rather large, zoophagous forms similar to desmans in their way of life.
Among birds in the Asian part of the Holarctic, the amount of endemic groups is rather insignificant. The crail family related to rallids and numbering several species in temperate areas of the northern hemisphere, are typical. The family of running rails, including the ostrich rail, is common across both Europe and Asia. True rallid birds have produced a number of species in marshes of Western Siberia and are common. Their migratory paths go above mountainous areas to the coast of the Indian Ocean, and some species spend the winter on the southern coast of Fourseas.
The true ostriches live in Asia only on the edges of the Mediterranean depression.
On the coast of the Arctic Ocean, representatives of an original group of cetornitids or gannetwhales, live; these animals are extremely specialized pelecaniform birds evolved into ecological analogues of seals and small dolphins. They lay eggs and bring up offspring mainly on the islands far from the continental coast. This group of birds has also settled on the islands of the Atlantic ocean.
Anseriform birds are diverse in the northern and eastern parts of Asia, and a significant number of species of ducks and geese live in the Far North. The bustardgoose, which lives in the dry steppe areas of Central Asia, is a large grazing species of bird. In the subtropics of the Far East, paradise ducks - waterfowl remarkable in the brightness of their plumage - are characteristic. Teratanatids, a family of birds endemic to Asia, is a group of large, flightless anseriforms feeding on macroalgae and aquatic flowering plants. The northern branch of this family lives along the northern coasts of the Pacific Ocean, while the southern branch is characteristic for the Oriental realm.
In the forests of northern Asia, pigeons are common, but their greatest variety falls to the Far East. Here is the northern border of the range of fruit doves - a special group of columbiform birds more typical for tropical forests of the Old World.
Large owls of the subfamily of griffon owls, including the largest flying birds, which exceed the size eagles during the age of man, live in the forests of the Far East. Other owls differ only slightly from the species known in the Holocene.
Another group of predatory birds, eagleravens, is widely distributed in the forests of Siberia and the Far East. One of the largest species lives on the coast of the Arctic Ocean. Forest-dwelling and mountain species differ from each other little, while rather small and long-legged species living on the coast of Japan differ from them strongly.
At the level of families, the variety of passerine birds of the Asian Holarctic remain comparable to the human epoch. Sawbeaks, semi-aquatic birds descended from corvids, are one family endemic to Asia. In the Far East, several species of these birds live, and some of them settled in mountainous areas of Central Asia, and one lives in Japan. The southern edge of the range of these birds is located at the edge of the Oriental realm.
Reptiles of northern Asia are not very diverse because of the continental climate with cold winters that interfere with the migration to the north of warmth-loving species. Tortoises, for the most part, do not live in the Asian part of the Holarctic; they live only in semideserts and bush thickets in Central Asia. In the Far East, there are several species of freshwater turtle. Tortoises, including rather large ones, inhabit Southwest Asia in areas of arid climate. In cold and temperate areas, lizards include only lacertids with few small or medium-sized species. In the south, agamids and monitor lizards enrich the hepetofauna. The running monitor from grasslands in Central Asia has evolved the ability to bipedally run. Southwest Asia has a richer fauna of reptiles. Desert jumpies, atypical agamids with the ability to jump and climb on plants with the help of well-developed hind legs, are one endemic group of this region. Huge, herbivorous pangolizard skinks also live here. Among snakes, very large, poisonous illuyiankas are remarkable; adders, elapids and colubrid snakes, including poisonous species, are numerous as well.
Among amphibians, the swampers - huge, caudate amphibians of the Western Siberian swamps, although they have relatives in temperate regions in eastern Europe - are very unique. Caudate amphibians are more diverse in the Far East, though they do not grow to such huge sizes as in Western Siberia. Anuran amphibians - toads and true frogs - are diverse. Among frogs of Siberia, there is a characteristic group called the dwarf midgefrogs; the adult individuals live only one season. In Lake Baikal, completely aquatic decendents of true frogs have evolved.
Fishes of northern and eastern Siberia are not very diverse. Among them, cyprinids, percids, pikes, salmons, whitefishes and ciscoes are characteristic. The diversity of the salmon family is much lower than in the Holocene epoch - a result of anthropogenic influence. Hardy representatives of eleotrids - descendants of Amur sleeper - are characteristic. They reach their great diversity in Lake Baikal, having superseded the groups that existed in this lake during the age of man. In the warm-temperate zone of Asia, catfishes of several families (true catfishes, bagrid catfishes, and bagariids in mountainous areas) live.
Among new groups of fresh-water fishes, sticklebacks frequently grow up to large sizes, and medium-sized sharks that have transitioned to life in fresh water are also common.
Among invertebrates, the fauna of Lake Baikal is remarkable in its richness and abundance of endemics. Also, in the early Neocene, the settling of some groups of decapod crustaceans in fresh water has taken place. In the Far East, freshwater decapods - crayfishes and shrimps - are diverse. Among insects, the variety of families remains largely the same, and a visible result of the general climate warming is the occurrence in the Far East of large species, including species belonging to tropical groups. In the swamps of China, mantids adapted for a semi-aquatic lifestyle have evolved.
To the south of the mountains, in India and Indochina, there is a different zoogeographic realm: the Oriental realm.
The mammal fauna is appreciably different from the Holarctic realm. The variety of artiodactyls is far greater in the Oriental realm. The family of thunderhorns, descendants of bovids, is endemic to Eurasia, and the majority of its representatives live in the East. In India, the nanditherium lives - it is the largest of its kind. Smaller and lightly built whistlehorns penetrate into the Holarctic realm: they live in Western Asia and the European maquis. Descendants of small Asian muntjac deer have evolved into large bull-like forms that inhabit both dry and marshy forests. Some species live far to the north, up to Japan. The rare shevrotain family inhabits swamps, forested riverbanks and mangrove thickets in the tropical zone of the continent.
In the Oriental realm, diverse Old World monkeys are characteristic; here, one group has evolved into the para-apes (parapongids). Some parapongids live in Holarctic realm, but the majority of species inhabits the tropics of Asia. Kong - the largest primate in the Neocene - belongs to this group. Also in the Oriental realm, other monkeys are typical - descendants of langurs and macaques of the age of man. Apes in Asia - gibbons and orangutans - died out in the Holocene or shortly thereafter, in a period of a great, global ecological crisis.
Predators of the Oriental realm are mainly felids and viverrids; canids and mustelids are less diverse. Cursorial descendants of mongooses live in the mountains of Central Asia. Heavily-built arboreal and ground viverrids live in tropical forests and in the foothills. The forest-dwelling predatory catshrew shows one attempt to compete with the true carnivores; it is a relict of an early Neocene radiation of insectivores, a singular attempt to occupy the ecological niche of small, arboreal predators. Among insectivores, only shrews and hedgehogs (absent on the Jakarta Coast) are widespread. Among shrews there is a remarkable large aquatic form - the phisonia living in the rivers of India; also, in mountainous areas, there are representatives of the aquatic shrew family. From the Holocene, pangolins have survived and among them, one specialized, burrowing species has evolved.
Among shore birds, various species of storks and herons are numerous and variable. In the order of anserine birds, the filter-feeding scoopbeaks have appeared. These birds have successfully adapted to the tropics of the Old World from Africa and Zinj Land through tropical Asia east to Meganesia. Ducks of various genera - from the large to the dwarf - are usual and widely settled.
Among wood birds, the parrots belonging to the group of true parrots are diverse. In Southeast Asia, in the point of contact to the Australasian realm, small species of cockatoo appear. In the Oriental realm, loreetos live; this is a group comprising a separate family of nectar-sucking parrots. They are endemic to the islands of Indonesia and the Jakarta Coast, and they represent a very deviant family in the parrot order that have converged on sunbirds, Nectariniidae, and hummingbirds. Swifts live mainly in the mountains, and in forests they are replaced by basket-mouths - specialized, insect-eating descendants of swifts. One kind of basket-mouth has penetrated to the Holarctic realm and inhabits the mountains of Central Asia.
The variety of pigeons is comparable to that in the Holocene; in the Neocene, in this order, a new family of fruit doves have evolved. Its representatives are large coorrows, numerous and diverse frugivorous forest birds of the Old World tropics.
In the Oriental realm, representatives of the falconiformes - hawks, eagles and vultures - have remained. One large eagle has developed an almost terrestrial lifestyle and lives on islands of Indonesia and the Jakarta Coast. Among hawks, the dwarf species that live in forest canopies are remarkable. Another group of flesh-eating birds of the Oriental realm includes large descendants of butcherbirds that have evolved into analogues of falcons and hawks. Eagleravens do not inhabit the Oriental realm.
In the Neocene, the faunal exchange between the Oriental and Ethiopian realms is much easier because of the split of Africa. There are no flightless terrestrial animals common to these realms yet, but among birds there is a family of spike-headed starlings that inhabit India, Indochina and Zinj Land. Among the nectarivorous birds of the Oriental realm, the endemic family of flowerpeckers is typical. From other passerine birds, primitive broadbills and pittas representing the Suboscines suborder are characteristic. Songbirds include finches, wagtails, flycatchers, titmouses, weavers, estrildid finches, corvids and many others.
Reptiles of the Oriental realm are much more diverse than in the Holarctic due to a more favorable climate. Tortoises have the greatest variety and, among them, large forms weighting up to 50 kg are not rare. Very large turtles of the emydids and three-clawed turtle families live in rivers, and small varieties are also diverse. In addition to turtles, representatives of an aquatic monitor family, common in Africa and Zinj Land as well, live in the waterways. Terrestrial monitor lizards also are diverse, and in Southeast Asia there are large species of them. Skinks, geckos and agamids are diverse; lacertids are rare. Snakes of the Oriental realm belong to numerous families. Among them, there are blind snakes, large pythons, and numerous colubrid snakes. Poisonous snakes include viperids (adders) and numerous elapids. Some snakes have also adapted to life in fresh-water.
The fauna of amphibians is distinct in the very small number of species of the Caudata order (there are a few species of newts and salamanders in the mountains of Central Asia). Anurans, in contrast, have a high diversity of species. Some have adapted entirely to life in the forest canopy, and do not need reservoirs for spawning. Some insular species of toads grow to great sizes whereas some representatives of tree frogs (Hylidae) are among the tiniest of amphibians. There are also digging forms living permenately in leaf litter. Also, caecilians - ground-digging and semi-aquatic worm-like species - represent a very bizarre group. Representatives of this conservative order have barely changed at all from the age of man.
Among freshwater fishes, the cyprinids, true loaches, and various catfishes (true catfishes, bagrid catfishes, schilbid catfishes, airsac catfishes, clarid catfishes, in mountainous areas also bagariids) are characteristic. Another important group of freshwater fishes includes the labyrinth fishes; the majority of which are small, but there are some large ones. Descendants of cichlids, introduced by humans, also became a characteristic component of the ichthyofauna of the Oriental realm. Snakeheads can grow to huge sizes, partly replacing crocodiles as the top predators of freshwater ecosystems. Eleotrids (sleepers) and freshwater gobies have acheived a great variety. Also in the rivers and lakes of the Oriental realm, the spiny eels (Mastacembeliformes) live; this group includes digging benthophags and ambush predators that feed on invertebrates and small fish. Descendants of introduced guppies have spread widely through the rivers of the Asian tropics, evolved into a number of species of small viviparous fishes. Garfishes, fresh-water pufferfishes and pipefishes are characteristic. In lower reaches of rivers, sharks, rays, flounders, grunters and croakers live. Mudskippers live in mangrove thickets.
The fauna of invertebrates is diverse due to a tropical climate. Insects are numerous, among which large species are not uncommon. Aquatic swallowtails are unusual - caterpillars of these butterflies lead an aquatic way of life. Large ichneumons parasitizing on vertebrates (including mammals) are endemics of the Oriental realm. Among two-winged flies the leechflies, which parasitize vertebrates, and scavenging infectioflies are characteristic. Among decapod crustaceans, fresh-water and terrestrial crabs are usual; some species grow to huge sizes. Some freshwater crabs have evolved to lead an arboreal way of life. Shrimps are various, but they are mainly small species; some shrimps inhabit cold mountain rivers. Large terrestrial leeches are characteristic inhabitants of tropical rainforests. These worms are also predators, feeding on small vertebrates.
|Rainforest of South-Eastern Asia|
|Inhabitants of Himalayas|
|Island in Indonesia, rainforest|
|Plains of China, swamps|
|Swamps of Western Siberia (not translated, Russian version only!)|
|Persian ridge - mountains replaced Gulf of Persia (not translated, Russian version only!)|
|The island in Kuril island chain (not translated, Russian version only!)|
|Mountain rainforests of Southern China (not translated, Russian version only!)|
|Baikal Lake and its inhabitants from surface to depth. (not translated, Russian version only!)|
|Rainforest of South-Eastern Asia and its inhabitants, animals and plants.|
|Eastern Siberia. Representatives of megafauna, their parasites, simbiotes and predators.|
|Karakum delta||Fourseas, delta of middle Asian Uzboy river; inhabitants of delta - birds and their neighbours. (not translated, Russian version only!)|
|The walley of hot lakes||Inhabitants of geothermal reservoirs of Kamchatka, wintering of migrating birds. (not translated, Russian version only!)|
|Jungle hermits||Life in jungles of Hindustan - megafauna and allies. (not translated, Russian version only!)|
|Slopes of ancient mountains||Life in mountains and valleys of Caucasus Peninsula. (not translated, Russian version only!)|
|Adopted in Eden||Steppes of Middle Asia, to the east from Fourseas, animals and plants. (not translated, Russian version only!)|
|Inhabitants of the kingdom of frost||
Small inhabitants of Eastern Siberia taiga - bats, birds, reptiles and invertebrates.
(written by Bhut) (not translated, Russian version only!)
In Neocene Africa makes a single whole with Eurasia. Gradual
movement of African lithospheric plate to the north began in early Cenozoic
and it had resulted in connection of Africa and Eurasia and in disappearance
of ancient Tethys sea. In himan epoch its rest, Mediterranean Sea, still existed.
But the further movement of Africa had caused the closing of strait of Gibraltar
in early Neocene, and as a result Mediterranean Sea had dried up, having left
the Mediterranean hollow – perhaps, the most inhospitable place for life at
the Earth of Neocene epoch. The presence of wast waterless area of land determines
in many respects a climate of northern part of Africa in Neocene.
The district along southern edge of Mediterranean hollow represents desert in which mountain plateaus are located in some places. Rains fall here extremely seldom – winds from Atlantic bring rain clouds so far into land area very seldom, and high Alpes stop rain clouds from North Sea.
Northern border of Africa is mark by Atlas mountains. They get a part of water carried by winds from Atlantic, therefore in mountains the short rivers appear and run into lakes and bogs at the bottom of mountains.
The largest river of Northern Africa is Saharan Nile. This river is not as deep, as its great predecessor of human epoch: after great split of Africa sources of White Nile are located in Zinj Land, and Saharan Nile exists only due to Blue Nile and some other inflows. Saharan Nile is the river meandering in Libyan Desert and merging with Niger river at the west. Valley of Saharan Nile is made of easily washing away deposits, therefore the river changed its channel for many times. For a short time Saharan Nile even abandoned its undercurrent, flowing down to Mediterranean hollow as a waterfall. But further the river made a new channel upstream and continued the way in Sahara, overflowing the channel and breaking up to the set of arms. Saharan Nile flows between Ennedi plateau and Tibesti mountains, includes a hollow of Chad lake into its channel, forms there a circuit of marshes and lakes, and continues flowing to the west, merging with Niger. In dry season the part of marshes and lakes in Saharan Nile valley dries up.
The northeast part of Africa represents a hilly landscape. Mountains take a part of rainfall from ocean, and in valleys short rivers and small lakes appear. Here the source of Saharan Nile – Blue Nile – is located.
The western coast of Africa is located in the field of influence of cool current and humid winds from Atlantic. Large rivers do not exist here, but lowlands along the coast are covered with marshes and from uplands bordering Sahara short rivers flow down. Summer temperatures are not too high here, and winter is humid and cool. But such microclimate is formed only along the narrow coastal strip. The presence of huge area of the deserts which are quickly heated up and quickly cooling down, results in sharp alternation of high and low temperatures: in the morning heating of air above Sahara causes movement of humid airmasses from the ocean, that bear fogs and rains. And at night the desert cools down quickly, and at the coast dry and cold wind from Sahara blows. Farther from ocean coast climate becomes droughtier.
Eastern coast of Africa represents mountain area, the result of split of the continent in early Neocene. In human epoch Great Rift Valley was here, in which there were lakes Nyassa, Tanganyika, Victoria and some others. In Neocene lakes had disappeared, and their coasts became a part of the coast of Tanganyika passage. Rains fall on hilly landscape, and the significant part of water flows to the west – into the valleys of Central Africa where the majority of inflows of large Congo river originates.
Central Africa represents the lowland surrounded with low mountains. When Zinj Land splitted off, Congo river had kept the most part of inflows and is the deepest river of Neocene Africa. Furthermore winds bearing rains from Tanganyika passage reach its basin much faster, rather than winds from Indian ocean in human epoch. In Central Africa rather equable, humid and hot equatorial climate dominates.
Southern part of Africa is rather dry hilly area. Here rivers are short and frequently dry up, and lakes exist for rather short time. To the south of equator Zambezi is the largest river. The low mountain ridges stretch along the coast, separating inner areas of continent from humid ocean winds, and the inner areas of Southern Africa represent savanna and semidesert. In some mountain valleys small lakes and marshes exist. The climate of these places is seasonal, differing in cool winter, short rainy spring and hot summer and an autumn. Namib desert had remained as barren area; its conditions became even more inclement because of the displacement of Antarctica aside Meganesia and the weakening of cold Benguela current. As a result the contrast of temperatures between sea and land is less expressed, and the amount of the moisture brought by fogs had decreased.
Types of vegetation of Africa depend directly on climatic conditions.
North of the continent represents the edge of Mediterranean hollow, the extremely
arid area with sharp daily temperature drop. Vegetation is extremely poor here:
trees are absent, and grassy plants are presented by drought-resistant perennial
grasses. Also in Northern Africa there are numerous species of bulb ephemeroids
of some families: Alliaceae, Liliaceae and Amaryllidaceae. Human activity had
left the trace in flora of Africa: it is the presence of cactuses, descendants
of prickly pear introduced by people. In deserts at the north of the continent
cactuses look as low non-lignifying plants.
Northwest of Africa is richier in vegetation, rather than the north. It is an area of Gibraltar isthmus and Atlas mountains. Here the rains moving from the ocean promote the growth of bushes and drought-resistant trees – oaks and laurels. In Atlas mountains pine trees closely related to European species grow, and in flora of Africa and Western Europe there are many common species of plants.
Along the Atlantic coast of Africa to the south of Gibraltar isthmus the special type of vegetation is formed; these plants have an ability to absorb and to stock a plenty of water from fogs brought from the ocean. The basis of plant communities here is made of plants of orpine family (Crassulaceae) and medium-sized succulent spurges looking outwardly like cactuses.
In northeast of Africa the communities of drought-resistant mountain plants are formed. Plant species growing there are closely related to ones from Arabia and Middle East. In areas nearest to the ocean palm trees and acacias grow alongside with other drought-resistant trees (belonging, in particular, to Anacardiaceae family), forming light forests. The zone of dense forests exists only at the coast where the most part of rains falls, and in valleys of Ethiopian mountains. Some species of Eucalyptus descending from plants introduced in human epoch grow here. In places where coasts are low and sandy mangrove forests grow, but their area is very small in comparison with forests of Southern Asia, because eastern coast of Africa is mostly rocky, and large rivers appear only to the south of equator (Zambezi).
To the south of deserts of Northern Africa the area of moderate amount of rainfall stretches, allowing to drought-resistant trees to grow. The main waterway of these places is Saharan Nile, the large river originating in mountains of Ethiopia. Along the river the complex of moistureloving marsh plants is formed: papyrus (not related to the species of human epoch), bulrush and large reeds. The large kinds of ground grasses also are various; they grow in places with sufficient humidifying and form dense thickets replacing fallen trees. On the islets in the channel of the river the moistureloving trees grow, forming small groves. In shallow backwaters various species of water lilies, Aponogeton, pondweed and other water plants develop.
Far from waters of Saharan Nile the vegetation of savanna type dominates; the typical feature is a prevalence of perennial graminoids and separate groups of trees, including the varieties casting off their leaves in dry season. One kind of trees of savannas of Northern Africa is a sugar tree, the baobab descendant. Also treelike succulent spurges having characteristic candelabrum-like crone shape are widely settled.
Coast of Gulf of Guinea is an area where continuous evergreen forests begin. At the northern coast of the gulf they are made of tree species adapted to seasonal changes of amount of precipitation, and closer to equator they are replaced by the species typical for tropical rainforest.
Central Africa (Congo river basin) is an empire of tropical rainforest, swamps and lakes. The wood flora of Central Africa was kept a little bit better, rather than in Asia and New World, because the countries of this region in human epoch were backward economically and the industry could not cause so great damage to the nature, as in other places. Besides the forest cutting was interfered by the unhealthy climate of these places favorable for development and distribution of diseases. Therefore tropical forests of Central Africa demonstrate the great degree of preservation and similarity to natural communities of Holocene epoch. Among trees of African tropical forests huge ficuses and also very large palm trees with plumose leaves more than 10 meters long are characteristic. In forests there are descendants of plants cultivated in human epoch: cocoa tree, rubber tree, some tropical fruiters and coffee. Among grassy plants descendants of cultural banana and its hybrids with wild species of banana are widely settled. Lianes are present as large species of aroid family oftenly having fanciful deeply dissected lobed leaves. Plants of family Dioscoreaceae, forming large ground caudex covered by suberizated bark, with long annual grassy stalks rising on the next trees are very characteristic. In mountain areas there are bamboo thickets, and in damp shady valleys treelike ferns grow. Epiphytic plants are characteristic for the top levels of tropical rainforest. They include ferns, spikemosses (Selaginella) and mosses, and also orchids and aroid plants.
At the coast of Gulf of Guinea mangrove forests grow. They are especially wast at the coast of Congo river.
To the south of area of tropical rainforests the territories of summer-green forests and tropical savannas spread. In southern hemisphere they have the smaller area, rather than at the north, because of a relief: the significant part of the south of Africa represents a dry hilly landscape. The tree vegetation is locally distributed here, in river valleys and near more or less long-existing lakes. Kalahari in Neocene remained a desert, but it receives little bit more water from rains, rather than earlier, therefore local reservoirs exist here till a significant part of year. For this area the seasonally growing aridophilous vegetation, including mainly graminoids, is characteristic. Light forests here are formed of plants of bean family – acacias and the related species capable to grow on poor soil due to nitrifying bacteria living on their roots.
The area of Namib desert had reduced because of expansion of savanna zone at the north from it. The reduction of amount of the moisture carried by fogs had resulted in impoverishment of desert flora and extinction of species more exacting to moisture. Aizoaceae of South Africa number plenty of species and form life-forms from succulent grasses up to low subshrubs. Only supersucculent species of them distinguished by slow growth and high abilities to storage and preservation of moisture survive in Namib desert. The true number of plants in Namib desert can be estimated only after pouring rain, approximately once in two or three years. Then all plants begin to blossom simultaneously and on monotonous background of desert bright spots appear – the beds of plants imperceptible before open flowers of bright colour appreciable from apart.
South Africa is a dry hilly area, and also Carroo desert. Dominant type of vegetation here represents light forests of treelike species of aloe, like in human epoch. Due to agriculture some species of aloe got an opportunity to survive, and in Neocene their descendants had restored the lost specific variety. Some species of these plants look similar to American agave. Also others succulent plants of Liliaceae family are usual here. Aizoaceae of mountain areas represent bushy plants with thick, sometimes even spherical leaves covered with glands and wax layer. At the eastern coast of South Africa descendants of cultivated pineapple grow.
Cap Floristic Region is located at the far south of Africa. Due to influence of ocean the local climate is more equable and humid, though it also cooler in comparison with arid areas at the north. Proteaceae and treelike heathers form forests and bush thickets on slopes of Cap Fold Belt along the coast of Africa. From among grassy plants various species of perennial geraniums, including subshrub kinds, and various kinds of Asparagus are characteristic. In deserts and semidesertic areas perennial ephemeroid plants – Iridaceae, Amaryllidaceae and Liliaceae – are richly present. Coniferous plants of South Africa are pine species (Pinus) descended from ones introduced in human epoch. They grow mainly in mountain areas. Eucalyptus is one more genus of introduced plants.
The fauna of Africa almost entirely belongs to Ethiopian zoogeographical
realm, except for the north of the continent which is included to Holarctic
realm. In Neocene the connection between Africa and Europe had became more expressed
after the forming of Gibraltar isthmus that had allowed to migrate freely between
continents to the representatives of various groups of animals; the originality
of African fauna is kept at the family level. A number of African groups of
animals had penetrated into the Western Europe, and in general there is greater
number of African migrants in Europe, rather than of European ones in Africa.
Predatory mammals of Africa are present as various species of felids and viverrids; other families are presented much poorer. Viverrids are settled at the whole continent and evolved to ground and arboreal forms which diet varies from strict meat-eating up to mixed with prevalence of vegetative food. One of large predators of northern part of Africa is deadlynetta, the saber-toothed animal of heavy constitution adapted to large prey hunting. In the same place with it smaller panther genettas live, being the ecological analogues of leopards. In tropical forests the number of species of arboreal viverrids grows, and one species has gliding membrane and inhabits tops of trees. In South Africa omnivorous ground viverrids live, able to eat carrion and leaves of succulent plants, and also pardinia lives there – the species adapted to chasing of swift-footed prey. In Northern Africa there is an endemic family of grumbling ant-mungos descended from viverrids (they are descendants the mongooses). These animals eat insects and are remarkable the ability to bipedal run.
South Africa is the house for the last species of hyenas of the Earth, the frightening marafil. It is one of the largest species of ground predatory mammals, eating large prey. Males and females differ in sharply expressed sexual dimorphism.
Felids of Africa are presented by descendants of small species of cats (last species of big cats, noonda, lives in near Zinj Land). Independently from each other some of them had grown up, but such kinds are not numerous. Barbed herzogcat, one of such species, lives in savannas of Northern Africa. The majority of small cats lives in forests of Central Africa, in mountains of Eastern and South Africa.
African mustelids represent not numerous kinds living in Atlas mountains and settled along the western coast of continent. In rivers of Western Africa, including Congo basin, some species of semi-aquatic mustelids live.
The representatives of canid family are various foxes, especially numerous in South Africa. These animals hunt small mammals, but there are also omnivorous and insectivorous varieties. The unusual representative of canids is chootie – the tiny species of foxes living in deserted areas of Northern Africa and eating insects.
Insectivores of Africa are rather diverse, and some of their representatives reach big size. The majority of African insectivores belongs to various species of shrews, and also to hedgehogs of typical shape livind everywhere on the continent. From Mediterranean maquis in foothills of Atlas mountains hedgejackal comes; it is the representative of original European group of predatory hedgehogs. Central Africa is a motherland of endemic family of wormtonguers. These heavy-built shrew descendants are the specialized analogues of anteaters, and one of their species lives in water, is good swimmer and eats aquatic invertebrates.
African chiropterans are diverse and inhabit in fact the whole continent, except for the most arid areas of Mediterranean hollow. Among them there are insectivorous and frugivorous forms, and also some predators hunting small vertebrates.
The most obvious feature of Holarctic influence to African fauna is the presence of various kinds of harelopes in northern half of the continent. They are the animals of open areas preferring dry climate. Among them there are the desert species able to exist without water drinking for a long time, but the majority of species belongs to savanna grazers. At the western coast browsing forms of harelopes live, preferring a mosaic landscape: open district with separate groups of trees and bushes. Whistlehorns, the original group of artiodactyls descending from bovids and living in semideserts at the edges of Mediterranean hollow represent an element of influence of Oriental realm to the fauna.
To the south of equator the not numerous family of tall browsing artiodactyls lives – the bonehorns similar to primitive giraffes. They are also descendants of bovids and endemics of Africa.
The most typical inhabitants of savannas of the north of Africa are representatives of hyraxes order. In Neocene descendants of small animals had turned to large ones and became more diverse in their habit of life. Savanna is inhabited by large four-footed herbivores – flathorns and embolohyraxes. “Semi-bipedal” ndipinotheres prefer light forests and live in a southern belt of savannas, and the most primitive kind of them, xenondipina, lives even in boggy forests of Central Africa and is able to swarm up trees. Semi-aquatic descendants of hyraxes are ipopos: reed ipopo inhabits river valleys, and sea ipopo settles in mangrove forests and can eat sea grasses. The attempt of hyraxes to become analogues of horses and antelopes resulted in appearing of hyracolope family endemic for the north and the east of Africa.
Among ungulates pigs make a competition to giant hyraxes. The boaropotamus lives in swamps and rivers of the north of Africa; it is the descendant of bush pig. In southern part of Africa the terrestrial group of descendants of bush pig lives – horned hogs distinguished in large size, heavy constitution (they resemble bulls or Clydesdale horses) and large bone outgrowths on muzzle. Horned hogs also inhabit Zinj Land, but local African forms have one unpaired horn on the muzzle, and at kinds from Zinj Land have thinner horns growing as a symmetric pair.
One more group received opportunities for evolution in Neocene are shevrotains. Some species of these ungulates live in tropical forests of Central Africa, and one large species of shevrotains lives in basin of Saharan Nile. In southern part of Africa the separate family of cursorial deerlike ungulates descended from them – false deer remarkable in their forked not falling antlers representing bony outgrowths of skull.
Rodents of Africa are as various, as in human epoch. Representatives of squirrel family are widely settled: they inhabit all forested areas of the continent, including tropical rainforest of Central Africa. In South Africa squirrel family is present mainly by ground forms, but at the far south, in Cap Floristic Region, the majority of their kinds is arboreal. Susliks live only in northwest of Africa, in area of Atlas mountains. Mice and rats inhabit the entire continent; in tropical forests there are many arboreal forms. Among rats there are large forest species eating firm nuts. These rodents are diverse in deserts of the south of Africa, and also in mountain areas at the east and northeast. The porcupines similar to species of Holocene epoch live in savannas and light forests, and jerboas live in arid areas. Very large rodents (mighty grasscutters and kangoohoppers) live in savannas of Northern Africa where the original complex of “new herbivores” is formed of large herbivorous mammals of new systematic groups first evolved in Neocene. Rodents of the south of Africa are more conservative.
In fauna of primates changes also took place. Apes had died out in human epoch or soon after its terminating, and their place in African ecosystems is occupied by baboons. Among baboons the forest-dwelling forms, some medium-sized arboreal species of tropical forest and also forms having bias to carnivorousness had evolved. The representative of the latter, the furiobaboon, has intelligence very close to level of apes and has some skills of tool making. Guenons settled farther to the north, to the Western Europe and to Gibraltar isthmus. They lead mostly arboreal or semi-arboreal habit of life and have well appreciable parts of brightly coloured hairless skin on head and various hair “ornaments”. Among guenons there are specialized arboreal forms, for example, dwarf squirrel guenons living in tropical forest in crones of emergent trees.
Also in Africa there are representatives of other groups of mammals: pangolines and elephant shrews.
The fauna of African birds in Neocene epoch is remarkable in variety; there are some endemic groups at the continent.
Ostriches were among the largest animals survived at the edge of Holocene and Neocene. Probably, they had survived due to human activity: people farmed them in captivity and had settled them in places where they had died out in wild. Neocene ostriches grow to giant size – the giraffe ostrich from savannas of Northern Africa is the largest bird on Earth. Other ostriches of smaller size live in zone of semideserts around the Mediterranean hollow; these ones are one-toed ostrich and the entire complex of related dwarf species in “oases” of Mediterranean hollow.
Anserine birds settled everywhere in Africa, living in places where there are constant or temporarily existing reservoirs. These are diverse species of ducks differing in diet, and mainly herbivorous geese. Among ducks there are the species filtering microalgae in top layers of water. Other water birds represent various kinds of herons, rails and moorhens. Some storks grow to very large size. Also for freshwater reservoirs and sea coasts gulls and terns are typical, and at the far south of Africa, at the sea coast, colonies of flightless penguigulls live. These birds became the ecological analogues of penguins of Holocene epoch, which had almost died out in Neocene. Sandpipers live at the coasts of freshwater and brackish reservoirs.
Gallinaceous birds represent only species of guinea fowl and pheasant families. Pheasant birds include descendants of quails and francolins, but among them there are also descendants of primitive breeds of domestic chicken turned feral in epoch of decline of mankind. Chicken descendants inhabit savannas, but live also in forests of Central Africa. Guinea fowls live in dry areas of southern and eastern parts of Africa, preferring savanna with separate islets of scrub vegetation and trees.
Among columbiform birds pigeons are widely settled, and representatives of fruit doves family – some species of coorrows – live in tropical forests of Central Africa and along the coast of Gulf of Guinea.
Parrots of Neocene Africa descend from rather small number of ancestors, including lovebirds and some parakeets. In savannas of Northern Africa among parrots there are the carnivorous species able to crack bones and being the original analogues of griffons and vultures. In addition to them in forested areas many varieties leading more typical habit of life live. One of such species is the beekeeper parrot adapted for feeding on stinging hymenopters.
Among woodpeckers the entire new group of carnivorous species appeared; the largest woodpeckers of Africa – large griffon woodpecker and related species belong to it. One of such woodpeckers is adapted to feeding on tortoises which shells it breaks by beack impacts. Alongside with these atypical woodpeckers there is a plenty of smaller species feeding on insects. Woodpeckers settle mainly in forested areas, but among them there are also the varieties living in treeless savanna and nesting in termitaries. The related group of honeyguides includes species with atypical diet – waxeater eats wax constructions of wild bees, and corpse bird (cadaverornis) feeds on dead animals.
In Africa coraciiform birds and cuckooes have great variety of species. Among Coraciiformes there are many kinds of halcyons – from small up to rather large ones. Cuckooes include the species which stand at different stages of the adaptation to brood parasitism. Among them there are insectivorous species, and also some predators hunting small mammals, birds and reptiles.
Among songbirds weaverbirds are very diverse; some of them nest in very big colonies or gather in flocks numbering tens thousand individuals. Among weaverbirds there are some species having unusual diet – partial haemathophags feeding on blood of large ungulates in parallel with extraction of parasites from under their skin. Crownhead birds living in tropical forests and light forests form the family endemic for Africa and related to weaverbirds. Also corvine birds are diverse. Some of them had occupied an ecological niche of ground hornbills of Holocene epoch: they are large ground birds eating insects and small vertebrates.
In fauna of reptiles the basic change is the replacement of crocodiles as dominant aquatic predators by other groups of reptiles. In Africa crocodiles had died out almost everywhere, and only in tropical forests the small group of descendants of dwarf crocodile was kept as ground predators of underbrush.
The place of large aquatic predator in Saharan Nile basin is occupied by crocoturtle – the giant variety of soft-shelled turtle attacking even water birds and small mammals. Tortoises are quite numerous; their greatest variety is observed in arid areas. Various turtles of emydid family live in rivers; one of their representatives, ink turtle, has a special way of protection against predators. At the eastern coast of Africa (coast of Tanganyika passage) algal turtle lives – it is a representative of tortoises adapted to life in sea water.
The tropical climate favours to existence of various lizards. For forested areas chameleons, mainly small or medium-sized, are characteristic. True lizards presented only by terrestrial forms live mainly at the north, penetrating from Europe through Gibraltar isthmus, and along the edges of Mediterranean hollow. Some true lizards at the western coast of continent had settled up to Central Africa. Families of tropical areas – agamids, skinks and girdle-tail lizards – are more typical for Africa. Agamas are very diverse in tropical forests and inhabit there mainly tree crones, and also they live in deserts. The original “grass fish” is an agamid having deep body compressed from sides and living in dense grass of savanna. Skinks are mainly digging or simply ground forms. Representatives of geckos are typical; usually they are small or medium-sized nocturnal lizards eating insects or small reptiles and amphibians. Some of them demonstrate fine examples of mimicry.
Monitor lizards are very diverse and often grow to great size. Among desert species there are active predators and scavengers. In Congo basin and to the south from it the role of large aquatic predators had passed from crocodiles to water monitors – the separate family of squamates related to typical monitor lizards. Water monitors live also at nearby Zinj Land.
Snakes of Africa belong to the same families, as in human epoch. Among colubrid snakes the kinds remarkable in strict specialization had evolved. Drillsnake eats only the contents of eggs of birds and large reptiles, and blind cavesnake is hermaphroditic reptile inhabiting caves and eating bat cubs and cave insects. In savannas and light forests at the north and northeast of Africa endemic wide-tailed snakes live – the insect-eating reptiles of gracile constitution. In adder family the thermovisor adder able to see infra-red radiation is remarkable. Various representatives of boa family live in tropical forests of the Central Africa and often reach very large size. Among them worm-tailed pythons had developed an original way of hunting with the help of tail serving for prey attraction.
At the territory of Africa only amphibians of orders Anura and Gymnophiona live. In Northern Africa anurans are numerous only in Atlas mountains and in Ethiopia, and at the edge of Mediterranean hollow their number is vanishingly small and only separate representatives of toad family live there. The greatest variety of amphibians is observed in Central Africa. Widespread and rather usual tongueless frogs, related to South American pipas – various descendants of clawed frogs – live here. In drier areas Microhylidae frogs live. Large trapmouth frog of true frog family inhabits river system of Saharan Nile and Niger. Its tadpoles are partly neotenic predatory forms. In forests tree frogs (Hylidae) are widely settled. Among them some poisonous kinds using “borrowed” poison of insects for protection had appeared.
Caecilians inhabit only forested areas with damp ground and thick layer of wood litter.
Fishes of Africa are most diverse in the central part of continent, in Congo river basin. Split of the continent had caused the extinction of numerous species of endemic fishes of Great African lakes. In rivers of Indian ocean basin there are freshwater and anadromous sharks, and some of their populations live in rivers all the time. Large freshwater electric ray inhabits the lower reaches of Congo. Also in lower reaches of rivers of Indian ocean basin stingrays are usual.
African lungfishes had survived and prosper despite of great age of this group of fishes; they live to the north from Congo basin, but one species lives in swamps of Congo and had lost an ability to go through drought season in cocoon. Also for Africa bichirs and reedfishes are characteristic; they kept from human epoch and changed only a few. The endemics of Ethiopian realm are mormyrids (elephant fishes) of the bone-tongues order (Osteoglossiformes); they often reach great size. The characoid order, common with South America, even in human epoch did not include any common family. In rivers of Central and Western Africa numerous characoid fishes of several families live. The majority of them represents small omnivorous and insect-eating forms, but also large herbivorous forms exist. Large characoids, barracuda phagos, are active fish-eating predators. Among characoid fishes in Neocene the separate family endemic for Central Africa had evolved – the comb-lipped tetras. These ones are specialized herbivorous forms eating floating plants, mainly duckweed. At the south and east of the continent cyprinids are widespread; in most cases they represent small omnivorous forms. Catfishes are represented by several families: upside-down catfishes (Synodontis and allies), airbreathing catfishes, bagrid and electric catfishes. From percoid fishes cichlids living in non-drying off reservoirs are very characteristic. Cichlids of Great Lakes have died out almost all at the split of Africa, and in ichthyofauna there are only few descendants of these fishes. The majority of cichlids of Africa represents descendants of mouthbrooders and related forms from Congo and Nile-Niger basins. The fishes adapted to air breath inhabit areas where seasonal drought is usual; such ones are snakeheads and labyrinth fishes. Characteristic fishes of rivers of tropical Africa are spiny eels – eel-like sand-digging forms of medium and large size, eating invertebrates and fishes.
At the far south of Africa galaxiid fishes live – it is a heritage of ancient Antarctic fauna.
Fauna if invertebrates is very rich, especially in forested. Among predatory beetles there are various tiger beetles, soldier beetles (including very poisonous ones), ground beetles, bombardier beetles and various lighting bugs. Polyphaga beetles frequently reach large size. In forests capricorn beetles and stag beetles, frequently having freakish horns, and also brightly coloured flower chafers are especially typical. Among wood-drilling beetles jewel beetles are usual. In savanna and light forests where large herbivores live, dung beetles live, including rather freakish ones. One of their representatives, the mirror beetle, lives in arid areas of the north of Africa.
Cockroaches inhabit mainly forested areas and belong to the same families, as in human epoch. Termites, including manure-eating ones, are diverse. Original complexes of species of invertebrates develop around constantly renewed manure heaps of large herbivores. Among butterflies swallowtails, pierids and nymphalids are typical. Ants are diverse in size and habit of life. One of the largest of them is a horror of tropical forest – large adumbulu ant. Numerous mosquitoes live in marshlands. Among flies there are parasitic forms – leechflies (some species are common with Oriental realm and even with Holarctic). Predatory and carrion-eating flies grow to large size; among them poisonous sambio robberflies attacking small vertebrates are remarkable.
Scorpions are usual everywhere in Africa. In arid areas they are very diverse, but mostly small, and in humid forest habitats large forms live. Large spiders are not rare; among them there are jumping spiders attacking lizards, and orb-web spiders making spiderwebs measuring some meters in diameter. In deserts of Northern Africa thumblespider lives – a particular species of wolf spiders. Also large centipeds, including poisonous scolopendras, are characteristic.
Ground snails are diverse; desert species developed the adaptations, allowing going through drought season. Ground leeches attacking vertebrates live in tropical forests. Freshwater leeches are diverse, among them there are large predatory fish-eating forms.
|Savannas of Northern Africa, large herbivores and predators|
|Savannas of Northern Africa, smaller animals|
|Nile-Niger - the largest river system of Northern Africa|
|Savannas of Northern Africa. (not translated, Russian version only!)|
|North African savanna - scavengers and dung eaters.|
|Fortress on the tree||Rainforest of Equatorial Africa, forest canopy. (not translated, Russian version only!)|
|Poisonous fellowship||Rainforest of Equatorial Africa, small inhabitatnts of the forest. (not translated, Russian version only!)|
|Between sun and salt||The migration of savanna dwellers of Northern Africa to Malta mountains. (not translated, Russian version only!)|
|Zambezi in Neocene||
Inhabitants of rivers and riverbanks of the east of Africa.
(written by Bhut) (not translated, Russian version only!)
The rift system in Eastern Africa in human epoch.
In fact Zinj Land (East African subcontinent) represents the
most mountainous part of Africa split away from the mainland. Maybe, Tanganyika
passage will turn to the ocean like Atlantic after many millions years, but
in Neocene it is rather narrow passage (the width of about 100 kms) completely
separating two parts of the continent being unite earlier. At the bottom of
Tanganyika passage volcanic processes express in full degree: from the bottom
hot springs sprout, and in some places underwater volcanos erupt. Eastern branch
of East African rift penetrates deeply from the north into the landmass of Zinj
Land, having formed the narrow Turcana gulf separating the northwest part of
subcontinent (about half of its area). Split of continental plate proceeds –
after some million years Zinj Land itself will split along the eastern branch
of East African rift. Earthquakes are often here, and from time to time volcanic
eruptions take place.
The prevailing form of relief of Zinj Land is mountain plateaus; the most part of subcontinent is elevated to 1 – 2 thousand meters above sea level and represents strongly eroded plateaus with the smoothed relief. In addition Zinj Land had carried away the highest mountains of Africa – Kenya and Kilimanjaro. The volcanic processes accompanying the split of Africa express not only under water, but also on land: along the coast of Tanganyika passage the long chain of young active volcanoes had appeared. Split of Africa caused also eruptions of Karisimbi and other volcanos, which activity was low in human epoch. Tectonic processes had caused a small inclination of eastern piece of African lithospheric plate that had caused changes in direction of river flowing.
Because of large height above sea level at the significant part of subcontinent dry climate dominates. All humid winds from ocean leave water in coastal areas making rather small part of the territory. According the degree of humidity it is possible to determine two areas of Zinj Land: western and eastern. The western part of subcontinent is a narrow strip between the chain of volcanos and coast of Tanganyika passage. Hillsides are abrupt enough, and coasts in some places are steep. Here there are only few rivers, and the existing ones are short, full of rapids and having numerous waterfalls. Only in the area of equatorial climate the western coast of Zinj Land gets enough rainwater for growth of trees.
Eastern part of Zinj Land is an area under the influence of winds from Indian ocean. Here rivers are more numerous and deeper. They flow in mountain valleys and consequently their channels had remained recognizeable even despite of time past from human epoch. In mountain valleys there are lakes, and in the central part of subcontinent, where Victoria Lake was located earlier, the swampland is stretched – it represents the rests of this lake. This place, between the coast of Tanganyika passage and Turcana gulf, is humidified rather well.
Northeast part of Zinj Land is more arid, rather than central one located in area of equatorial climate. Due to plentiful rains in valleys of central and southern part of Zinj Land rivers flow and lakes exist.
In general the flora of Zinj Land and Africa is very similar.
The difference is caused by features of relief of Zinj Land – here vegetative
communities, characteristic for mountain areas, prevail obviously, and there
are some unique communities of Alpine flora of tropical origin.
The northwest part of Zinj Land is an area of savannas and light forests. Graminoids and drought-resistant trees – acacia, baobabs and Eucalyptus – grow plentifully here. The latter trees are descendants of the species introduced by people in historical epoch, naturalized and evolved successfully. In this part of subcontinent moistureloving kinds of plants grow only in river valleys. Closer to the coast of Turkana gulf savannas are replaced by light forests where acacias dominate.
Northwest coast (the coast of Tanganyika passage) represents the place of the least favorable conditions for plant growth. Fewer amounts of rain fall here, rather than at the eastern coast at the same latitude, and in flora drought-resistant species prevail obviously. In this area succulent spurges with reduced leaves and prickly candelabrum-like stalks, and also large kinds of aloe grow.
The significant part of territory of Zinj Land has the complex relief combining lowlands and heights, and the results of it are variety and mosaicism of landscapes. At the highlands condition are drier, and here the various kinds of graminoids forming high grass savanna, and also separate species of trees prevail. The grassy plants not related to graminoids grow in such places less often and settle mainly on slopes where graminoids do not form the continuous turf. In gorges and river valleys more humid microclimate develops, and it favours to development of tree vegetation. Along river valleys some species of trees of tropical forest penetrate from eastern coast farther to the west, where at the highlands species steadier to dry conditions dominate. For such places palm trees of various genera are characteristic; quite often the same species grows in different number both in forests and in savanna.
In Alpine areas the unique complex of species of tropical by origin, but cold-resistant Alpine flora develops; such plants have leaves covered with wax or hair for protection against night colds. In mountain areas very large plants of Asteraceae family grow – mainly bushes, but some ones are treelike. Among grassy plants and non-branching lignifying “grass trees” plants of Gesneriaceae and Lobeliaceae families prevail. During the blossoming thickets of these species are decorated with bright flowers involving birds and insects. From Alpine meadows up to lowland marshes various species of genus Sansevieria are widespread. Among them there are the undersized plants forming dense turf, and large kinds with gristle-hard leaves.
Large areas of tropical rainforests may be found only at the coast of Indian ocean and in southern part of subcontinent. The variety of plant species comparable to forests of Central Africa is typical for them; the difference is expressed at the level of species within the common genera. In mountain forests in the south of subcontinent the bamboo of various species grows, forming continuous thickets. In high mountains the special type of mossy forest is developed, where the number of species of mosses and lichens is very high. Also in mountain forests tree ferns grow, forming an underbrush in areas of rarefied forest stand. A result of human influence to flora is the presence in Zinj Land forests of eucalyptus species descending from the varieties introduced in historical time. Eucalypts of special varieties adapted to life in conditions of tropical rainforest make the uppermost level, towering above forest canopy one by one or in small groups. New group of plants for forests of subcontinent is the group of begonia trees – woody plants evolved at the islands of Indian ocean and inhabited also the coasts of Asia and Madagascar.
On flat eastern coasts of Zinj Land in rivers mouths mangrove forests grow plentifully. At the coast of Tanganyika passage mangrove thickets are rare, and only in depth of Turcana gulf mangroves occupy the extensive areas, but their specific structure is much poorer, rather than at the Asian coast.
The fauna of Zinj Land belongs to Ethiopian realm and inherits
many features of African fauna.
The sign group of Neocene fauna of African mammals is the hyraxes order. Their evolution at the continent had caused the rising of diverse forms of large herbivores inhabiting various ecological niches. Hyraxes of Zinj Land are more conservative: they had not formed such freakish forms and have kept more features of similarity to ancestors. Various species of horned conies live in forests and mountains, being remarkable by bone outgrowths on nose bridge. One of endemic groups is ashkokos family including tree-climbing browsing forms, and among them very large (ngoloko) and highly specialized (ventrohyrax) ones. From continental descendants of damans on Zinj Land sea ipopo lives – the species able to cross sea passages. It lives at all coasts of Zinj Land, especially at the eastern coast of subcontinent where mangrove forests are more usual.
Elephant shrews had reacher the special variety on Zinj Land. Some of their kinds had developed new habitats: there is one species living in mountain streams and similar to desman. The majority of elephant shrew species represents medium-sized forms from arid areas of northeast of Zinj Land, but there is a large omnivorous form from tropical forests of the south and southeast. Insectivorous mammal include hedgehogs living mainly in savanna area, and shrews widespread everywhere at the subcontinent. On Zinj Land representatives of aardwark group had survived. Very large species of these animals is megaardwark, the bipedal animal eating insects and carrion.
Herbivores are presented by numerous ungulates. Ruminants include various goatlopes descended from feral domestic goats. They greatly vary in size from small ones up to very large kinds, eat grass and leaves, and are most diverse in savannas and light forests. In tropical forests various horned hogs live; their size is from small up to medium. Horned hogs of Zinj Land are forms having two large paired horns, as against to one-horned African ones. Some horned hogs penetrate into savanna. Harelopes could not penetrate to Zinj Land, and it had allowed to be kept to the initial fauna including ungulates. Among them domestic goats began to dominate quickly and had superseded descendants of other groups.
The whole subcontinent is settled by large rodents, among which “the armoured porcupine” cataphractherium is the largest one. The majority of rodents, however, is present by small and medium-sized species. Among them there are digging, ground and tree-climbing forms belonging to mice, squirrel, hamster and porcupine families.
Primates of Zinj Land include various prosimians descended from bushbaby, and also guenons, both ground and arboreal ones. Bushbaby descendants are mainly zoophagous, live both on trees, and on the ground; in tropical woods there are some almost completely ground-dwelling species. Guenons are most various in mosaic landscape of northeast of the subcontinent.
Carnivores of Zinj Land at the family level are similar to African ones. In fauna canids (descendants of foxes and the jackal), mustelids, viverrids and felids are present. Canids are most various on open spaces – at the highlands of northeast part of subcontinent. Forest-dwelling are more rare – they are replaced by representatives of other families. Among viverrids mongooses and civets – the ground-dwelling forms living in forests – are diverse. The majority of felids and all mustelids are small predators (among mustelids there are aquatic ones). Among large predators of subcontinent the last representative of large cats (genus Panthera) – noonday, the descendant of leopard – is remarkable. The part of smaller predators is taken not by cats, but by large cat-looking viverrids (maladomini).
Chiropterans have the greatest variety in forests where numerous frugivorous and nectar-sucking forms live. In addition to them there are separate species of predatory chiropterans hunting small vertebrates. In northeast of subcontinent mainly small insectivorous varieties live, exterminating blood-sucking insects near herds of large herbivores. Alpine bats exist in conditions of low night temperatures; therefore they fly in daytime and run into catalepsy at night. The solar flying fox lives in top level of tropical forests; it is large, slowly flying and mainly tree-climbing kind of flying foxes.
The fauna of birds of Zinj Land expresses a lot of similarity to African one: the common features are noticeable at the level of orders and the most part of families. In Zinj Land ornithofauna, nevertheless, endemic families exist, which had appeared after its split off the African continent.
Dwarf forest-dwelling ostriches live in forests of subcontinent; they are similar in anatomy to African species. Also there is a medium-sized omnivorous species of ostrich in savannas of northeast.
Water birds are most diverse in southern and central part of subcontinent, and also in lowland areas along the coast of Indian ocean. The flamingos, preserved from human epoch, almost had not changed, as against the species from Mediterranean hollow, and inhabit lakes in northeast (in savanna zone) and in a southwest, near to Victoria marshes. Fauna of stork birds is rich: storks, including rather large ones, herons, and also original social hammer cop forming numerous colonies in coastal thickets and boggy woods. In marsh lands various rails and allied forms live; the part of their species is adapted to life in high grass savanna. Also at the marshes various swamphens and coots, and also numerous sandpipers live. Small sandpipers live at the sea coasts. Anserine birds include various species of ducks and geese, including various forest ducks living in boggy woods of southern part of subcontinent. Some kinds of ducks live in mangrove forests at the ocean coast.
Among ground birds Coraciiformes and related groups reached the great variety. Representatives of this order include various species of halcyons, bee-eaters and rollers. Halcyons are most diverse in Victoria marshes and in river basins of central and eastern part of Zinj Land. Bee-eaters inhabit mainly savannas of northeast part of subcontinent, and rollers and related forms live in forested areas of subcontinent.
A variety of falcon birds is apparently lower, than in human epoch. Large eagles and griffons, and also falcons had died out, but hawks and kites survived. Also there is a descendant of harrier developed the convergent similarity to secretary birds of human epoch.
Owls are numerous in forested areas where large kinds live, being similar to eagle owls of human epoch in size. In savannas owls are mainly small species living in tree groups. Some species of owls living in wetlands of Zinj Land catch fish and frogs. One small species of owls eats tree-climbing frogs, searching them aurally, listening for their voices. The barn owl family is diverse and includes several small species.
Nightjars, birds related to owls, are the representatives of family Caprimulgidae (typical nightjars) and are diverse in savannas and in mountain areas with sparse vegetation.
Cuckoos are most various in forests where there is a plenty of large forms of them. All of them are brood parasites, and mainly various passerine birds feed their nestlings. Only separate species live in savannas, but for breeding they migrate to forested areas.
Woodpeckers and related birds live mainly in forests of subcontinent. Some kinds are common for Africa and Zinj Land: waxeater (in tropical forests) and corpse bird (in savannas and light forests). In forests true woodpeckers are diverse, and bone-breaking woodpeckers live in savannas of northeast of Zinj Land.
Columbiform birds of the subcontinent represent various species of pigeons and coorrows. Pigeons are widespread everywhere, including the deserted areas of the western coast of subcontinent, where they make regular migrations. In savannas small flocking seed-eating species of turtle-doves live, and in forests there are large pigeons of bright colouring, eating seeds and fruits. Some large kinds of ground-dwelling pigeons kept ability to fly live in forests of a southern part of subcontinent. Coorrows (fruit doves) are exclusively forest inhabitants and live in southern and eastern part of the subcontinent. They avoid a competition to pigeons due to arboreal way of life.
The greatest group in number of species present at Zinj Land is the group of passerine birds. At the level of families the fauna of songbirds is similar to fauna of Africa, but there are some unique, and even endemic families. One of them is spike-headed starling family, the descendants of true starlings widespread also in Southern and Southeast Asia and at the islands of Indian ocean. True starlings also live in forests of subcontinent. Evolution of corvids of Zinj Land had resulted in appearing of new groups of birds. One of them is Resonatornis genus uniting the forest-dwelling birds remarkable in very loud voice. Also in Zinj Land and nearby islands the endemic family of crestbills exists; these are forest birds with bright vertical outgrowth on upper mandible. Among them there are both forest-, and ground-dwelling forms, mainly omnivorous and frugivorous. From smaller songbirds in Zinj Land titmouses and Old World flycatchers, and also finches, weaverbirds and estrildids live. Dippers, the inhabitants of rapid streams in mountains, make the unusual component of local ornithofauna. Maybe, their settling here had taken place during the ice age through Northern and Northeast Africa. At the south of Zinj Land coastal dippers live; they live at the sea coast and search for food in shallow water.
In conditions of tropical climate in Zinj Land reptiles are very diverse. Among tortoises the species having freakish outgrowths at the forward edge of carapace had appeared – collarbill tortoise and “fanged” tortoise. Alongside with them many kinds of tortoises of more typical appearance live in savannas of Zinj Land. At the coast of Tanganyika passage algal turtle lives; it is a secondarily aquatic herbivorous species of tortoises. Freshwater turtles (of families Emydidae and Trionychidae) live mainly in eastern and southern parts of subcontinent.
Lizards are very diverse. Among them geckos live in forests and rocks and have great variety; some forest-dwelling species have camouflage adaptations and are active predators. Also agamas and chameleons, and in plain areas also monitor lizards are various. The family of water monitors characteristic for tropics of Old World is presented by crocodile monitor lizard living in rivers; in Zinj Land it is smaller a little, than the continental form.
Among snakes pythons are various – from small up to very large ones of some meters long. Some pythons live in water and leave it only for egg laying. Among colubrid snakes the darter snake is remarkable. Among ground-dwelling and arboreal snakes adders are usual.
Amphibians of Zinj Land belong only to anurans and caecilians. Caecilians include various species of common caecilians, and very small and brightly coloured ones among them. In wood litter some large kinds species of caecilians live. Anurans are representatives of true frogs, toads, microhylids and tree frogs. Among fully aquatic frogs tongueless frogs are characteristic and include various species of clawed frogs.
Fishes of Zinj Land show the obvious relationship with African ones. In rivers some species of sharks and rays live; some of them inhabit only mangrove thickets and river mouths where the influence of sea inflow is expressed, and others can rise far upstream. From dipnoan fishes only one species of African lungfish lives here and other primitive fishes represent bishirs similar to their relatives from human epoch. From freshwater fishes of African origin elephant fishes live here, and among them deadly phyllomormyrus had developed the ability to produce very strong electric impulses. Characoid fishes are not numerous in comparison with inhabitants of African continent. The largest kind of these fishes in Zinj Land is Usambara characid trout, the inhabitant of mountain rivers. Cyprinids in many respects replace characoid fishes in rivers of subcontinent. Among them there are numerous small and brightly coloured barbs and rasboras, and also herbivorous kinds like Potamolabeo. Catfishes of several families live in fresh water: these are upside-down, clariid and bagrid catfishes and some other ones. In lower reaches of rivers sea ariid catfishes. Cyprinodontid fishes have plenty of species at the northeast, in areas of seasonal climate, where they live in temporary reservoirs. Descendants of guppy introduced by people live everywhere in constant reservoirs. Among perciform fishes snooks (glass perches and Lates species descended from Nile perch) and cichlids are characteristic. The part of cichlid species represents the descendants of species of Great African lakes, which had receded to fresh water at the split of Africa and flooding of lakes with water of Indian ocean. From among cichlids disproporcichla, the fish having clearly expressed sexual dimorphism, and cuckoo chromis leaving its eggs to these fishes are interesting. From the fishes closely related to perciforms spiny eels live here – various species of genus Mastacembelus. In river mouths fishes of sea families and orders live: flounders, moonyfishes and scats live. Also for rivers of Zinj Land pufferfishes are typical – there are sea species coming into fresh water for a while, and also completely freshwater species.
The fauna of invertebrates is very rich. For savannas and forests various termites and ants, including army ants dangerous to the majority of animals of small and medium size, are characteristic. In various landscapes social bees are widespread – these are the descendants of domestic honey bee widely settled by people. From two-winged flies large poisonous sambio robberflies and parasitic leechflies, and also various mosquitoes, especially numerous in marshy areas, are characteristic. Various lepidopterans live in forests, including large swallowtails and hawk moths. Among beetles dung beetles are characteristic; their variety is connected to the variety of ungulates in savannas.
Spiders and scorpions, among which there are large species, are numerous and various. Some kinds of centipeds reach very large size and are poisonous.
Terrestrial molluscs frequently reach large size and have brightly coloured shells. Among freshwater molluscs the digging species of Melaniidae snails living in marshlands in wet soil had evolved.
Among worms the large earthworms are characteristic and have an important role of soil-makers in savanna. Various leeches live in fresh water and on land.
|East African subcontinent (Zinj Land), rainforest. (not translated, Russian version only!)|
In Neocene the geography of Madagascar almost had not changed,
because the island had almost remained its former place in relation to eastern
coast of Africa, having only moved a little bit farther to northeast when the
split of Africa and the formation of Zinj Land had taken place. The distance
between Madagascar and some islands of Indian ocean (Mascarene islands, Seychelles
and Comoros islands) remained former: they had also “shifted” farther to northeast,
having remained in former position relatively to Madagascar. It is connected
with the fact, that all these islands are a single whole with eastern part of
African lithospheric plate which had broken up in Neocene.
Madagascar is the island of continental origin, a splinter of Gondwana. Its geology is very stable: the island is far from the centers of tectonic activity, nearest of which is the “fresh” split separated Zinj Land from Africa. Volcanic activity at the island is almost absent, and only sometimes the earthquakes take place, being the echoes of geological processes proceeding under the continent. The geography and climate of island also resemble those in Holocene epoch: the centre of island is still mountainous (Central High Plateau is located there), in the west sparse forests and savannas of different degree of aridity stretch, and at the eastern coast of island climate is more humid and there semi-deciduous broadleaf forests grow. Nevertheless, in Neocene slopes of Central High Plateau became less bold due to erosion; also both western and central areas of Madagascar became more humid, than had been before; semi-deciduous broadleaf forests had penetrated also to north- and southwest of island. It also is connected to slight shift of island to the north, therefore the climate of northern part of island began more humid.
At the east of island a plenty of bogs and lakes had formed; they exist for rather short time – thousand and tens thousand years. But due to enough rainfall they are full of water all year round. The majority of reservoirs of the western part of island, on the contrary, depend on seasonal changes of weather and can even dry up in dry season or turn to mud traps. Large lakes are absolutely absent on plains, but some lakes exist in mountain areas of island. Rivers of Madagascar start flowing on Central High Plateau. In eastern part of island they are rather narrow and short, and in western part are much longer.
The review is written at participation of Bhut, the forum member.
The flora of Madagascar in Neocene has kept an originality,
that had been its identity in human epoch, though because of human activity
alien elements had appeared in it, and the part of unique kinds has died out
as a result of destruction of habitats and deforestation. Some representatives
of local flora have a leading position in forests of the island. Among trees
at the west of the island there are various acacias, and also baobabs – the
descendants of those not numerous species managed to resist to anthropogenous
influence and climatic changes at the boundary of Holocene and Neocene. Acacias
prosper in arid areas of island and represent the prepotent kind of trees of
Madagascar; some species had settled even in foothills.
At the western coast of island there are areas of deciduous broadleaf forests almost completely casting off foliage in dry season. But in savannas there are also original communities of treelike succulents. They are composed of succulent spurges, large kinds of aloe and descendants of prickly pear cactuses introduced by people. They keep fresh green color even in drought, and edible fruits of cactuses involve inhabitants of surrounding savannas to these forests. In the beginning of rain season aloe and cactuses begin blossoming and thus involve set of pollinators from among birds and insects. In addition in savannas of island, and also at the hillsides many species of low grassy succulent plants from Crassulaceae and Euphorbiaceae (spurge) families live.
At the eastern half of island, in humid forests, palm trees are very diverse and the overwhelming majority of them are endemics. Legume plants represent here large trees visible because of bright flowers on the background of green colour of crones of surrounding trees. One more typical plant of island is Ravenala changed only a few from human epoch. Fan-shaped crones of this plant rise in places, where rivers cut through continuous forest thickets. Brightly coloured flowers make appreciable trees and bushes of dogbane family, among which there are many poisonous species. Eucalypts introduced in human epoch also had successfully naturalized and had given rise to new varieties widespread at the island and developed new ecological niches. New group of plants is the begonia trees group, fast-growing and diverse species of which do not reach large size.
At the sea coast in many places mangrove plants grow. Some of their kinds managed to adapt to fresh water and penetrate deep into island area where they form rich thrickets in the rivers and bogs in common with Pandanus trees (screw palms). Other species of mangrove trees dominate right at the sea coast of island, forming even the original plant analogues of reeves of Holocene – they breed with the help of root offsprings which grow from parental plant and penetrate far into the sea, in shallow water areas constantly filled with sea water.
There are no papyrus species at Madagascar, but there are some related forms of sedges family, which form dense thickets at the coast of freshwater reservoirs. Endemic kinds of canes (descendants of both indigenous species and ones introduced by people) adjoin to them, and at the east mangrove tree species adapted for fresh water join to them. Among aquatic plants representatives of Aponogeton genus are characteristic, and among them there are numerous endemics. Some of their species live in drying up reservoirs and exist during the dry season as leafless tubers. Also in freshwater reservoirs various bladderworts, water lilies, eel grass and other plants of tape-grasses (Hydrocharitaceae) family live.
Lower part of slopes of Madagascar mountains is covered with bush-like scrub – on eastern slopes it is composed of acacias, on western slops – of bamboo. Also on slopes and in valleys gum trees grow. Mountain tops are covered with mainly grassy vegetation forming there the unusual savanna with some trees and bushes – mainly these are acacias, but in more damp places palm trees and bamboo grow also.
From among grassy plants in eastern part of island orchids and epiphytic ferns have the greatest variety. In the west, in savannas, kinds of flowering plants are more various at the level of families; the majority of them is anemophilous. Flowering plants and ferns in variety and original appearance do not concede to the kinds growing in jungle of Africa and Asia. Among them the per cent of endemic forms is great.
The review is written at participation of Bhut, the forum member.
The fauna of Madagascar in Neocene still keeps the singularity
though in human epoch it had grown poor relatively to local endemics and had
got a lot of elements unusual for it – mostly domestic animals.
Mammals of Madagascar in Neocene include, first of all, various lemurs. Among them the Lemuridae family is most various; also there are representatives of Cheirogalidae and Indriidae. Among lemurs analogues of ground-dwelling monkeys and even the kangaroos developed the life on open plains had evolved. Other lemurs had stayed in forests; among them the forms similar to sloths, and jumping forms having a rudimentary flying membrane had appeared. The majority of lemur species belongs to omnivorous or herbivorous animals, but among them the specialized insect-eating kinds, and also some kinds having bias to carnivory had appeared.
Another typically Malagasy mammals are tenrecs, unusual insectivorous inhabitants of Madagascar forests and savannas. Some of them became very large in comparison with the ancestors – up to pig-sized ones. The majority of tenrecs still represents medium-sized zoophagous or omnivorous varieties; among them there are ground-dwelling, digging, tree-climbing and swimming forms. Rodents are presented mainly by families Nesomyidae (endemic Malagasy family) and murids (descendants of introduced mice and rats). Among them there are medium-sized arboreal varieties, and also many inhabitants of mountain areas and savannas at the west of island.
Carnivores of the island belong to four families – felids, canids and viverrids (descendants of the species introduced by people), and also Malagasy predators (more rare and specialized descendants of local kinds). Among them there are ecological analogues of leopards, cheetahs and mustelids. Canids and long-legged viverrids live mainly on plains, and felids, the most part of viverrids and Malagasy predators inhabit forested areas, bush and mountains of the central part of island.
Chiropterans are very numerous and various – their number and variety had appreciablly increased after the restoration of island ecosystems. They include various bats (sac-winged bats, free-tailed bats, vesper bats, etc.) and flying foxes, both endemics, and relatives of the species living on Zinj Land.
Birds of Madagascar also express originality, as well as mammals, but the degree of endemism of island avifauna is less, than in human epoch. In swamps and in savannas various kinds of stork birds (storks, herons) and flamingos, survived in epoch of ecological crisis, live. Flamingo of Madagascar represents the species common with Zinj Land, formed stable populations at the reservoirs near the western coast of island. Other water birds of island are cormorants, related to kinds from Zinj Land, grebes, sandpipers and ibises. Gulls are not numerous and live at the sea coast, and near freshwater reservoirs various terns settle.
Anserine birds of island represent various kinds of anatid birds common with Zinj Land (differing at the subspecies level) or related, but endemic species. Geese and swans are absent, but ducks are various, and among them there are forest-dwelling ones nesting on trees of tropical rainforest of eastern part of island. Coots and related birds are various.
The most remarkable bird of Madagascar is large flightless gallinaceous bird – Numidornis descended from introduced guinea fowls. It had occupied an ecological niche of Aepyornis extinct in Pleistocene-Holocene and competes successfully to lemurs and tenrecs as large herbivorous inhabitant of island. Other gallinaceous birds are some kinds of quails.
Among smaller forest birds parrots are remarkable; some of them can be compared by the sizes and colouring to some birds of Holocene epoch, like macaws of South America. They descend mainly from lovebirds (Agapornis) of human epoch, but there are also some parakeets, the descendants of later migrants from Zinj Land. Pigeon birds compete to them in brightness of colors, and among them there are some local species of coorrows. Birds of prey represent the descendants of hawks and kites, and also owls. Among owls the largest species are local varieties of barn owl family; representatives of true owls are small, mainly insect-eating birds or hunt small vertebrates. Madagascar cuckooes (including large carnivorous kinds) and coraciiform birds (rollers, halcyons, hoopoes and some others) are very diverse. Passerine birds of the island include the limited number of families, among which there are weaverbirds and estrildids, corvids, Old World flycatchers, vangas, starlings (descendants of introduced myna) and sunbirds.
Reptiles of Madagascar also show a high degree of endenism, despite of the damage suffered in human epoch. The majority of their species belongs to squamates order: they are snakes and lizards, and chameleons first of all. On Madagascar the largest chameleon of Neocene lives – the darter chameleon, and also there is one of the smallest ones – leaflet chameleon. Chameleons compete in species variety to geckos among which there are not only insect-eating, but also frugivorous kinds. Geckos of tropical forests oftenly develop skilful ways of masking, and the species from mountain habitats differ in abilities to climbing on steep rocks. Some widespread kinds form many locally distributed subspecies. Also on Madagascar skinks and gridle-tail lizards live; some of them grow to large size. Poisonous snakes are absent, but there are medium-sized boas.
In addition to lizards and snakes Madagascar is inhabited by cheloniids, both tortoises and freshwater turtles. They descend from the species settled from Zinj Land after human disappearance; local kinds had quickly died out in epoch of ecological crisis.
There is very small number of amphibians of Madagascar; all of them are representatives of Anura order – these are frogs (Mantellidae, Microhylidae and true frogs).
Diversity of fishes of Madagascar is not so great, and the ichthyofauna of the island is rather poor, despite of the tropic location of the island: it is connected to long-term isolation of island. Among fishes there are not numerous descendants of local fishes: Ateriniformes (Malagasy rainbowfishes), gobies, ariid catfishes and pupfish. These fishes are connected in their origin to sea-dwelling forms. Endemic Malagasy cichlids were rare in human epoch, and they had died out completely in epoch of ecological crisis. They had been replaced by descendants of Mozambique tilapia widespread in human epoch as an object of commercial fish culture. Influence of human activity had left its spot upon ichthyofauna of the island as the presence of descendants of snakehead fishes introduced from Asia, and largemouth bass from North America. They were the reason of extinction of many groups of Malagasy fishes, and their descendants had occupied the majority of freshwater reservoirs of island: descendants of largemouth bass prevail in flowing waters, and snakehead descendants inhabit still and frequently drying up reservoirs. As for plant-eating fishes, island is inhabited by descendants of introduced giant gourami and carp. Also viviparous fishes inhabit the island – descendants of guppy and swordtails introduced by people. But their variety is not comparable to variety of viviparous fishes in Caribbean Sea and Central America.
The fauna of invertebrates is rich and expresses originality. Insects of Madagascar include butterflies (Urania species among them) and moths (saturniids and hawkmoths), flies, beetles, termites, mantids etc. These kinds are endemic in the majority, but are also rather recent immigrants from Zinj Land. Various non-stinging bees are remarkable. Walking sticks, cockroaches and soothsayers sometimes grow to large size. Among others invertebrates arachnids are especially numerous. Some spiders have horn-shaped outgrowths on abdomen, and also there are huge orb-web spiders. Myriapods live in tropical forests – large millipeds and poisonous scolopendras. Large gastropods are widespread in forests. Some snails descend from giant African land snail and grow to huge size.
The review is written at participation of Bhut, the forum member.
|Western part of Madagascar, humid savannas. (not translated, Russian version only!)|
|Call of lemur||Rainforest at the east of Madagascar. (not translated, Russian version only!)|
In Neocene the geography of Australia had undergone the essential
changes connected to proceeding movement of Indian and Australian plates to
northwest. This movement is restrained by the edge of Chinese part of Eurasian
plate that had resulted in amplification of volcanic activity in Big Soenda
isles area. The main result of it was the uniting of Australian continent and
New Guinea island; the continent formed during this process has the name Meganesia.
The reason of this uniting was the movement of Australia to northeast and the
raising of the part of lithospheric plate at the north of the continent. Also
Meganesia included some smaller islands at the northern coast of Australia and
near New Guinea. As the consequence of formation of Meganesia, two very big
lakes were formed at the north of this continent: Arafura Lake (former Arafura
Sea) and Carpentaria Lake (former gulf of Carpentaria). The Carpentaria Lake
was separated from the ocean earlier, and its water became almost fresh. Arafura
Lake is still salt-water, because it has connection to the ocean through complex
circuit of channels in extensive mangrove thickets, but its salinity is lower,
rather than in oceanic water. Both lakes are surrounded with extensive zone
At the north of Meganesia sea had receded, but in the south there is an opposite situation. Here shallow Eyre Gulf penetrates deep into landmass. It is separated from the ocean by shallows and tongues of sand, and is connected to it through narrow passage. Shallow-water and well warmed up by sun, Eyre Gulf is poor in oxygen, and its water may be freshened due to river runoff and rain water. Fluctuations of salinity may be rather significant – from half of oceanic salinity value up to almost fresh water. All these circumstances create the certain difficulties for life of animals inhabiting it. In the center of an entrance to the gulf the small Flinders island is located; in human epoch it was a mountain ridge. The short flatland rivers, and also Murray, the deepest river of Meganesia, run into this gulf. Tasmania island in Neocene is still an isolated part of land, but in ice age it had connected to the continent for some times.
In Neocene Meganesia had considerably shifted to northeast and moved closer to islands of Indonesia, but had kept its geographical isolation. Some small islands of Indonesia had sunk and became shallows near to Meganesian coast. Movement of tectonic plates had provoked active orogenesis at the north of the continent: mountains of New Guinea, had been rather high already in human epoch, had grown even more in Neocene. At the east of the continent another mountain chain is stretched – Great Dividing Range. The processes of orogenesis do not proceed here any more, and these ancient mountains erode gradually. However on this ridge the largest rivers of Meganesia originate. The part of the rivers, however, originates in swamps and forests surrounding Carpentaria Lake and flows into Eyre Gulf.
Climate of Meganesia in Neocene epoch turned more humid both due to geographical changes, and due to the general worldwide increase of humidity. North of the continent is located closely to equator, and here it is a hot climate and there are plentiful rains almost every day. However, despite of nearness to equator, in mountains of northern Meganesia it may be rather cold, and at mountain tops snow the year round lays. Most part of Meganesia is located in a zone of tropical climate with alternation of drought and rain season. Except for Murray and its inflow Darling, local rivers are short. Many of them exist only in rain season, and in dry season they represent dry channels only. Some rivers flow under the ground the year round. Lakes are small and frequently drying up. Eyre Gulf softens climate of the plains around of it. At the southwest of the continent the climate becomes drier and hotter. The majority of reservoirs is temporary here, except for springs. At the east of Meganesia, to the east of Great Dividing Range, the zone of humid climate stretches: here air masses from Pacific meet mountains, and as a consequence, plentiful rains fall. Far south of Meganesia and Tasmania represent the areas of subtropical climate. In mountains of Tasmania climate is temperate, and winter is cool.
The review is written by Simon, the forum member.
Flora of Meganesia is a direct successor of Australian and New Guinean florae, but its originality has smoothed out in the certain degree due to activity of people, which had introduced to tis area a number of the plants non-native and alien to Australia and New Guinea. Forest vegetation of Meganesia is made generally of plants of three families: myrtles (mainly gum trees), legums (acacias) and Proteaceae. Also Nothofagus (southern beeches) and araucarias take part in formation of Meganesian forests.
The diagram of natural zones of Meganesia
Picture by Timothy Donald Morris (Australia)
Northern part of Meganesia is in the field of equatorial and
subequatorial climate. Here every day rain falls, and constantly high temperature
promotes growth of tropical rainforests. Among characteristic vegetation of
these forests there are many groups common with Asia: treelike ficuses, palm
trees with plumose leaves, Santalaceae, laurels and Magnoliaceae. Here plants
of Australian and New Guinean origin represent some kinds of gum trees and other
myrtles. Large woody lianes are presented by rattan palms, and grassy ones are
various kinds of Piperaceae family (peppers), frequently having patterned smooth
leaves. Among epiphytes lichens, mosses and ferns have great variety. Epiphytic
“staghorn ferns” and Asplenium ferns, frequently having integral leaves, are
very characteristic. From among epiphytic flowering plants orchids expressing
similarity to East Asian genera are plentifully presented. Among trees of tropical
rainforest Laportea species are remarkable – these ones are treelike representatives
of nettle family, having very burning leaves.
The area of Arafura Lake is remarkable in largest areas occupied by mangrove forests on the Earth of Neocene epoch. The zone of mangrove forests many kilometers wide separates this lake from the ocean, weakening the movement of tidal waves and forming a changeable circuit of channels and shallows. Coasts of the lake are also overgrown with salt-resisting mangrove trees. Underwater plants of Arafura Lake are the representatives of “sea grasses” able to grow in salt water. Only in river mouths there are separate representatives of freshwater flora, able to endure short-term salinization of water. Carpentaria Lake is more ancient, and its water is considerably freshened (there is only residual salinity, of about 1 ‰). Accordingly, the structure of environmental vegetation is changed: the lake is surrounded with thickets of screw palm (Pandanus), palm trees and other trees, able to endure flooding or to grow in shallow water, and the hydroflora of the lake is considerably richier.
As a result of movement of the continent the mountains, belonging earlier to New Guinea, became even higher, and in northern part of Meganesia the phenomenon of altitudinal zonation is expressed: as the altitude above sea level grows, tropical rainforests of lowlands are replaced by less thermophilic mountain forests, which gradually pass to thickets of mountain bushes and Alpine meadows. The characteristic trees of mountain flora of northern Meganesia are Casuarina, Nothofagus and tree ferns, forming rich underbrush in shadow of trees forming forest canopy. At tops of highest mountains of Northern Meganesia snow lays, and below the border of snow the zone of vegetation of tropical origin adapted to sharp daily temperature drops is formed.
Eastern edge of Meganesia receives more rain water, rather than western one, and zones of vegetation are displaced in appropriate way. To the south of zone of tropical rainforests the zone of scrub – tropical bushy vegetation – is stretched, which from the west to the east gradually passes to area of boggy savannas. During one year this area of continent receives various amount of moisture – from plentiful humidifying in rain season up to extremely poor in dry season. As a result of it the vegetation in scrub area represents undersized bushes (mainly Proteaceae and eucalypts), and in boggy savanna separate groups of high trees grow, and a significant part of vegetation represents perennial rhizomatic grasses able to endure drought. In this area there are many reservoirs, drying up in dry season (for 2 – 3 months), and there mainly rhizomatic and bulb aquatic grasses grow, able to endure seasonal drying of reservoir – water lilies and Aponogeton.
The specific complex of vegetation develops on the side of Great Dividing Range turned to Pacific ocean. The significant part of the rains from Pacific ocean falls here, and the favorable conditions for growth of forest vegetation are formed here. Forests of eastern slopes of Great Dividing Range are formed mainly by gum trees, araucarias and tree ferns. In such forests palm trees are almost absent, and at higher altitudes in mountains there are pine treed, descendants of the kinds introduced by people.
At the western slopes of Great Dividing Range the transitive zone between mountain vegetation and the vegetation typical for plains at the appropriate latitude is formed.
To the south from the zone of tropical rainforests the conditions, optimal for forest vegetation, develop in southeast part of Meganesia. Here semi-deciduous broadleaf forests grow, adapted to existence in conditions of seasonal change of amount of precipitations. The majority of trees in such forests belong to myrtle family (mainly gum trees) and Proteaceae. Crones of gum trees pass enough sunlight to the ground; because of it in such forests the rich underbrush is formed. Dominant species of underbrush are bush plants of Rosaceae family – descendants of introduced and run wild blackberry. As well as in human epoch, in forests representatives of sundew family are plentifully presented – perennial grasses, sometimes growing to large size. To the south of tropical rainforests epiphytic orchids are absent, but their ground species are diverse.
Along the rivers of Murray basin boggy sites stretch; they have typical marsh vegetation – large broadleaf grasses. Aquatic plants include bladderworts, floating aquatic ferns, water lilies and Aponogeton species. In marshes in conditions of temporary flooding some orchids grow.
Great Dividing Range does not pass a significant amount of rain water to internal areas, therefore a significant part of continent in the centre and in the west represents arid savannas with small areas of tree vegetation. Graminoids dominate here, but there are also representatives of other families of plants. In dry season savannas have monotonous yellowish-brown color, and the plants growing here differ from each other very little in leaf shape and color. But after rains the view of savannas changes sharply: the majority of plants blossoms and plains turn coloured brightly.
Eyre Gulf represents well-warming shallow reservoir around of which more favorable conditions for growth of plants develop. At the coasts of gulf jarra is formed – the kind of plant community, where bushy eucalypts represent the main part of the community, and the rest is a small amount of plants of other families. In gulf there is a variable salinity of water dependent mainly on amount of precipitation, therefore in shallow water thickets of aquatic plants, resistant to changes of salinity are formed – mainly, the special kinds of “sea grasses”, and also descendants of fresh-water plants resistant to salt water. In mouths of rivers running into Eyre Gulf water has more stable low salinity, therefore thickets of Pandanus, little bit similar to mangroves, are formed here. The interlacing of stilt roots of these plants give a refuge to numerous kinds of fishes and invertebrates. Especially large Pandanus thickets grow in Murray delta, at southeast coast of Eyre Gulf.
Southwest of the continent is the most arid part of Meganesia. Semideserts are located here, and the vegetation differs in poorness and presence of adaptations for survival in arid conditions. From among trees in deserts of Meganesia there are Proteaceae species having very thick water-stocking trunk, and also “bottle trees” with high and obese trunks, growing in small groups. The wood vegetation grows near temporary reservoirs where water is available for some weeks. There are only few succulents similar to cactuses, aloe and spurges in Meganesia, and only some species have separate features of succulents. But in deserts of Meganesia there are many annual ephemeric plants surviving in drought as seeds and quickly developing after rain. Some plants form water-stocking underground tubers, and on ground surface only leaves and flowers are visible.
In mountain areas of Meganesia and in Tasmania the climate is close to temperate, but there are no frosts. Here not exacting to heat ferns of various species dominate, including tree ferns. Forest vegetation is made of southern beech, and also conifers – various species of Araucaria and descendants of pines introduced by people. As a whole the flora of Tasmania differs in great part of endemic species.
Fauna of Meganesia belongs to Australian realm. But many animals
of Neocene Meganesia are descendants of the species introduced by people and
occuring from other zoogeographical realms.
Mammals represent various systematic groups. Monotremes (platypus species and echidnas) are endemics of Meganesia. They are more diverse, than in Holocene. Descendants of echidnas sharply differ in size – from giant stegoechidna up to small forms, among which there are arboreal and burrowing species. From platypus specialized aquatic mammals descend.
Marsupials of Meganesia are very diverse, in spite of the fact that the part of their specues had died out at the boundary of epochs (marsupial wolf, marsupial devil, koala). Representatives of primitive dasyurid family (predatory marsupials) and the families “branched” from them in early Neocene occupy niches of insect-eaters and predators. Predatory marsupials of Neocene are descendants of marsupial rats, marsupial mice, kultarrs and native cats (quolls). Among small species there are extremely specialized forms – such, as marsupial bloodsuckers, marsupial shrews and Embryotherium. Some of them turned to burrowing forms. Others – the representatives of spike-tailed marsupial rats family – became partly herbivorous and seed-eating forms. Large predatory marsupials resemble felids, but among them there are also the kinds not similar to any placental mammal – marsupial sharp-toother, for example.
Kangaroos, the original “logo” of Australia, had also continued evolution in Neocene Meganesia. They inhabit both plains and woodlands. In addition to typical kangaroos, unusual species had evolved: heavy-built hook-fingered kangaroos and ostrich kangaroos adapted to fast run. The family of trunk kangaroos includes the species of unusual appearance, which became partly omnivorous. Among true kangaroos in неоцене there are also scavengers, and even predatory forms.
Everywhere in Meganesia marsupials of possum family are usual. Many of them descend from Holocene brush-tailed possum, very numerous species adapted for life near to people. Arboreal species of cuscuses and families related to them (for example, flying possums) live in tropical forests and light forests. From possums two new families descended. These are large predatory possums resembling bears and competing successfully to dasyurids, and marsupial lemurs, cuscus descendants with more advanced brain and complex social behaviour – they are analogues of primates.
On plains of Meganesia huge grass-eating yamooti wombats live. As a whole, however, the wombat branch is not numerous and declines gradually.
Except for bats and part of rodents, placental mammals are obliged to people by their existing in Meganesia. Not all introduced ones survived up to Neocene: so, predatory mammals – cats, dogs and mustelids – had died out because of epizooties of rabies and canine distemper. But ungulates of Meganesia take the important place in ecosystems. At the north of the continen deer and pigs live, and in Carpentaria Lake there is bovipotamus, semi-aquatic representative of bovid family, the descendant of Asian buffalo. To the south, on plains and in light forests various camelids live – from rather small camelopes up to large Caballocamelus and huge giraffamel Dolichocamelus.
Chiropterans of Meganesia are various and include both flying foxes and microchiropters. True bats belong to several families, and their diet varies widely – from nectar up to insects and small vertebrates. The largest species is silent flying wolf, a predatory bat of false vampires family (Megadermatidae), living in light forests. The majority of species of chiropterans inhabits tropical forests at the north of the continent.
All numerous rodents of Meganesia belong to murid family. They descend both from native kinds settled in Australia as far, as in Pleistocene, and from rats and mice casually introduced by people. These animals inhabit all types of landscapes and express a variety of forms among which aquatic and semiaquatic species, and also jumping rodents of savannas and deserts are remarkable. In fauna of Australian realm also mammals of Lagomorpha order are present. All of them descend from European rabbit introduced by people. Meganesian rabbits are similar externally to rabbits and hares of Holocene Eurasia, but one species of them had deveploed the aquatic environment.
Birds of Meganesia became more numerous, rather than in Holocene. As against to mammal, introduced kinds of birds could not achieve success on this continent: only few of their kinds have the descendants in Neocene.
Largest birds of Meganesia are flightless and belong to order Casuariformes. From emu very large false moas, similar to ostriches and occupying various biotopes had descended. Some descendants of cassowaries turned to zoophagous ones: one of them catches fish, and another one, yagil, is one of top predators in tropical forests in northern Meganesia. But the majority of species of these birds (false moas) represents omnivorous forms having bias to herbivory.
Gallinaceous birds of Meganesia descend mainly from local species of quails. At the north of the continent some descendants of megapodes and feral domestic chicken live.
At the coasts of freshwater and brackish reservoirs anserine birds live – ducks, swans and scoopbeaks; also there are sandpipers, gulls, terns, grebes, cormorants and rails. Stork birds include herons and ibises, among which haruspex is remarkable: it is the ibis turned to specialized scavenger. Gulls, terns, cormorants and some tubenoses inhabit also sea coast of Meganesia. At the southeast coast penguigulls live – they are the representatives of group of birds, characteristic for Antarctic Region and Subantarctic.
The majority of predatory birds of Meganesia belongs to falcon birds order – for example, hawks, falcons (descending from small specues), kites, buzzards and harriers. The largest feathery predators and scavengers of Meganesia descend from Australian vedge-tailed eagle, one of few eagles survived in human epoch. In addition to falcon birds, in Meganesia also nocturnal predators live – barn owls and true owls (boobooks), and among the latter there are very large forms.
Pigeons (some of them lead a terrestrial way of life in tropical forests), cuckooes, bee-eaters, halcyons (including kookaburra descendants) and swifts are numerous. Woodpeckers are not present, and animals of other groups (for example, possums) are their ecological analogues. Parrots are more diverse, rather than Holocene ones, and belong to cockatoo and true parrot families. The nightjar order includes several families and is widespread everywhere on the continent, from forests up to deserts.
Passerine birds of Meganesia are rather diverse. Some families are common for Meganesia and Eurasia: corvids, larks, starlings (including descendants of introduced European starling), thrushes, Old World flycatchers (and related families), wagtails, swallows, cuckooshrikes, timaliids, pittas, sylviid warblers, white-eyes and others. Also estrildids are widespread, and among them the group of Meganesian weaverbirds is separated; also there are true weaverbirds presented by descendants of introduced house sparrow. Many families of passerine birds are endemic for Meganesia and nearby islands: these are bellmagpies, bowerbirds, birds-of-paradise, pardalotes, malurids and many others. From malurids, or fairywrens, in Neocene the family of running malurs descended.
The fauna of reptiles of Meganesia is very rich. Representatives of few kinds of crocodiles remained on Earth, sawjaw crocodile (Carpentaria and Arafura lakes) and sharkodile (tropical sea waters) live here. Freshwater turtles are presented by snake-necked turtles, which variety was reduced a little in comparison with human epoch. However the largest turtle of Meganesia, Brontochelys, descends from introduced red-eared slider from Emydidae family. Other species of emydids are widespread in fresh waters of Meganesia, including drying up reservoirs. In seas surrounding the continent, there are marine turtles belonging to families evolved only in Neocene; large bat turtles are among them. Squamates represent the most various group of reptiles. Lizards belong to geckos, skinks, agamids and to some other less numerous families. The family of monitor lizards is the most typical for Meganesia; among these reptiles awful dracovaranus is remarkable – it is the top predator of deserts at the west of the continent. The majority of monitor lizards of Meganesia inhabits open spaces though there are some forest-dwelling species having skills of tree-climbing. All monitor lizards eat smaller vertebrates, but among them there is the atypical species eating social insects. Snakes belong to pythons (among them there is eingana, the largest snake of the planet), elapids, colubrids, blind snakes and some other families. As well as in human epoch, in Meganesia of Neocene epoch there is a plenty of varieties of poisonous snakes. In seas sea snakes still live, but their variety is lower, than in human epoch: pelagic species had died out in epoch of global ecological crisis, and there are only descendants of less specialized shallow-water forms.
Amphibians of Meganesia belong only to Anura order. Tree frogs, microhylids and representatives of myobatrachid family are most typical; true frogs are not numerous. The important place in ecosystems is occupied by descendants of introduced cane toad.
A variety of freshwater fishes of Meganesia is rather poor. Representatives of Galaxiiformes, Ateriniformes and Perciformes orders live in freshwater reservoirs. Galaxias had evolved a great number of fresh-water and anadromous forms differing from each other in habit of life and features of anatomy. In arid areas there are fishes of this order capable to survive for a long time in protective capsule when the reservoir dries off. Ateriniformes are presented mainly by rainbowfishes and their descendants. Due to competition to descendants of introduced fishes their variety had decreased in comparison with human epoch, but rivers are inhabited by endemic small species of these fishes remarkable by brightness of colouring. From among percoid fishes grunters and croakers live in fresh waters of Meganesia. Freshwater species exist also among cartilaginous fishes – sharks and rays. The medium-sized species of freshwater sawfish lives in rivers. Giant dipnoan fish named bunyip is endemic; it is a descendant of Neoceratodus which managed to survive due to its man-made settling and protection in human epoch. Many freshwater fishes descend from sea species; these are flounders, eeltail catfishes and others. They often spend only a part of life cycle in fresh water, moving to the sea water for spawning. Some fishes descend from the species introduced by people – carps, tilapias and trouts. Descendants of trouts inhabit upland streams of rivers of Great Dividing Range. Cichlids had settled the north and east of Meganesia, avoiding salt water of Arafura Lake. Cyprinids prefer peneplain rivers of eastern Meganesia (Murray basin). In mangrove thickets various species of mudskippers live.
Invertebrates are very numerous, especially in tropical forests. Insects, and among them beetles and butterflies are most diverse. Dung beetles descended from African species introduced by people represent a group of insects new for Meganesia. They inhabit mainly plains where ungulates live. Everywhere on the continent termites live; many kinds of them build impressive constructions. Among cockroaches there are very large species having long life cycle. Arachnids are widespread: spiders and scorpions are usual; among spiders there are many poisonous forms. From among crustaceans decapods reached the greatest successes: crabs live near water and in tropical forests, and shrimps partly replace freshwater fishes in lakes and rivers. Crayfishes inhabit rivers from cold springs up to warm boggy lower reaches. Molluscs reach the greatest number of species in forests and in freshwater reservoirs, but among them there are also the species adapted successfully for life in desert. Some freshwater bivalves are able to endure complete drying of reservoir within several years in succession.
Ground leeches living in forested areas represent the characteristic group of tropical invertebrates. They are especially plentiful in tropical rainforests at the north of the continent and in bogs of Murray river valley.
The review is written by Simon, the forum member
|Meganesia, fauna of savanna|
|Meganesia, Murray river (not translated, Russian version only!)|
|Deserts of south-west of Meganesia. (not translated, Russian version only!)|
|Voices in the night||Rainforests at the north of Meganesia. Nocturnal animals of various forest levels. (not translated, Russian version only!)|
|Dream about the gone sea||Mangrove forest at the north of Meganesia, shores of Arafura Lake. (not translated, Russian version only!)|
|Carpentary Lake in Northern Meganesia, animals of shores, deepwater parts and surrounding forests. (not translated, Russian version only!)|
|Life of Zooraptor||Megafauna of Meganesian savannas: birds and mammals. (not translated, Russian version only!)|
|One hundred days for life||South-western Meganesia, temporary desert lake and its inhabitants. (not translated, Russian version only!)|
|Garden of Earthly Delights||Forests of Southern Meganesia and their inhabitants - predators
(written by Timothy Morris)
|Dragons of Eyre Gulf||
Large reptiles of Eyre Gulf at the south of Meganesia and their migration for egg laying.
(written by Bhut)
The Neocene geography of New Zealand differs from Holocene
one only a little. Aotearoa still remains isolated archipelago of two large
islands, North Island and South Island separated by Cook Strait. Their coastal
line is cut up strongly, and there are fjords on South Island. At the coast
numerous smaller islets are located. In ice age they merged to main islands,
but after its ending had been separated from them again. Far from coast of New
Zealand some rather large islands are located: Chatham archipelago in the east,
Antipodes in southeast, Auckland islands in the south and some other.
Because of movement of lithospheric plates New Zealand shifted a little to northeast. The archipelago is under the influence of the process of gradual reduction of Pacific ocean in full degree: in New Zealand there are earthquakes periodically, and from under the ground in some places geysers erupt. There are also some active volcanoes.
Relief of New Zealand is mountainous. The most part of New Zealand has a height more than 100 meters above sea level. The largest mountain chain crossing both large islands is Southern Alps. At tops of mountains of South Island there are glaciers, but their area is much less, than in Holocene – it is a consequence of warmer climate. In addition to mountains and heights, in relief of Aotearoa extensive valleys are present. Also the presence of plenty of cave systems is characteristic.
Climate of archipelago is warmer, than in human epoch. North Island of New Zealand and the most part of South Island are located in zone of subtropical climate. In the south of South Island there is a zone of temperate climate. Ocean renders great moderating influence to climate. Due to its influence there are almost no frosts in New Zealand (except for the south of South Island) and summer heat, and the temperature of air varies in a little degree within the year. In mountain areas the climate becomes rigorous – here it is a zone of Alpine climate. For New Zealand the high humidity is characteristic: western winds bring moisture here. Southern Alps block way to a part of air masses; therefore the east of New Zealand receives lesser amount of rainfall, than the west part.
Rivers of New Zealand are mainly short and deep; they flow down from mountains. Also at the archipelago there are many lakes formed in mountain valleys.
The review is written by Simon, the forum member.
The vegetation of New Zealand still keeps features of uniqueness,
despite of great influence which human activity rendered in historical epoch.
The number of endemic taxa in New Zealand flora had appreciablly decreased in
human epoch; it is connected to changes in fauna of islands: herbivorous ground
mammals had appeared, and the plant species better adapted to trampling and
eating away by them got an advantage in struggle for existence.
On North Island the complex of more heat-loving vegetation had developed. At the western side of islands, receiving more rainfall, forests of gymnosperms – cauri (Agathis) and Podocarpus species – dominate. These plants survive due to longevity and plenty of seeds – the significant part of young trees perishes because of mammal, and flowering plants compete to them at the broken areas of forest. On branches of large trees numerous epiphytic ferns and mosses expand. From among descendants of native plants in forests there are large treelike representatives of Pseudopanax genus, and also fuchsias – descendants of local species Fuchsia excorticata. There is also a small number of representatives of genus Hebe – treelike Veronica relative; their variety, however, had appreciablly decreased. In bottom level of forest, especially at the sites of damaged forest stand, species of Clematis expand – these are lianes growing up to great height. These descendants of the species introduced by people make forest impassable, and only few insects can eat their foliage. Palms are presented by only few species.
At drier eastern sides of islands the variety of epiphytes in forests is lesser, and forest stand is more rarefied. Rather high undergrowth of bushes develops here.
Higher in mountains forests with prevalence of descendants of native kinds are replaced by pine woods formed by descendants of introduced radiate pine. In underbrush of such forests the blackberry of local kinds prospers – it is also the descendant of the species uncharacteristic for native flora. On dry and sun-warm northern slopes of mountains forests are formed of acacias being descendants of species introduced from Australia. In damp valleys and in river valleys the communities formed by species of Nothofagus (southern beech) and tree ferns prevail.
In high mountains the vegetation of the Alpine type dominates – these are undersized cushion plants and spreading bushes. Dwarf pines with branches trailing on the ground grow here alongside with hardy evergreen plants, including Hebe species superseded here by descendants of introduced species. On Alpine meadows graminoids and perennial species of lupins (descendants of Lupinus polyphyllus) prevail. Variety and success in struggle for existence of introduced legume plants is connected to presence of pollinators from among social wasps introduced by people.
Marshlands of North Island are occupied by Cordyline of local varieties, competing successfully with descendants of introduced species of plants. In shadow on damp places rich thickets of local Tradescantia species, descendants of introduced Tradescantia fluminensis, are formed. Some species of Tradescantia from Aotearoa turned to aquatic and amphibious plants. At the south and in mountains, in area of warm-temperate climate, thickets of willows, descendants of species introduced by people, are usual.
In river mouths and at the coast of islands thickets of Pandanus, usual for tropics of Old World and Oceania, are widespread.
South Island has a little bit cooler climate: in general, the subtropical climate turns to warm-temperate at far south. Accordingly, the structure of vegetation also differs. In particular, in forests there is lesser number of epiphytic ferns, but mosses are more diverse. In mountains there are relic vegetative communities of Holocene epoch, the vegetation of temperate climate – forests of Nothofagus and tree ferns. At the south of island such forests are widespread and form extensive thickets, but tree ferns prefer cooler mountain climate and plentifully expand in shady damp gorges less accessible for herbivorous mammals. Also for forests treelike Hebe species with beautiful bright flowers gathered in large inflorescences are characteristic. Near to them bushy and treelike broom species with flowers of white and yellow color grow. For forests of South Island thickets of climbing species of honeysuckles with thick woody trunks are characteristic. In the underbrush kinds of blackberry and barberry (descendant of Berberis darwinii introduced from South America) usually grow.
In Alpine areas of South Island cold-resistant evergreen grasslands develop, forming dense sod cover.
In rivers throughout New Zealand descendants of introduced aquatic plants are usual: large species of eelgrass, forming extensive thickets by vegetative reproduction, Egeria and Lagarosiphon. Only after people aquatic fern Ceratopteris got to New Zealand, but the local kind of small floating Azolla fern successfully competes to it. Among native hydrophytes of New Zealand in Neocene aquatic mosses are richly presented.
During all Cenozoic era the fauna of New Zealand had almost
completely lack mammals and developed in isolation. Numerous endemic birds,
and also unique reptiles and amphibians lived here. People had broken the ecosystem
of New Zealand in essential degree: at first Polynesians had introduced the
first alien species (rats) and had started the extermination of local animals,
but this process had reached apogee in epoch of European colonization of archipelago.
Neocene fauna of Aotearoa keeps the signs of influence of mankind extinct a
long time ago: some endemics had died out completely, and many animals of Neocene
epoch descend from introduced species. After the extinction of mankind the settling
of islands by new species from Australia/Meganesia and Polynesia, mainly by
birds, has proceeded. Thus, the fauna of Neocene New Zealand consists of three
components: small number of descendants of native kinds, usual and widespread
descendants of introduced species and few species descending from Neocene migrants.
All mammals of Neocene New Zealand, except for several species of bats, descend from the the species introduced by people. Large mammals inhabit the main islands of archipelago and islands near the coast, and on the remote islands they are presented only by rat descendants, or are absent at all.
The New Zealand marsupials mainly descend from brushtail possum introduced from Australia. Some of them are herbivores, and others turned to predators forming the endemic family of paradasyurids (New Zealand predatory marsupials). These two evolutionary lines are crowned by giant ursine cuscus and marsupial pardus. However, among the New Zealand descendants of brushtail possum there are also smaller species, including arboreal ones, which have kept a habit of life close to ancestral. Also on islands small kangaroos live.
All insectivores of Aotearoa are descendants of European hedgehogs. Among them there are both tiny shrew-like creatures and rather large animals specialized in feeding on social insects.
New Zealand chiropterans are presented by several species descending mainly from Australian migrants and belonging to vesper bat family. Flying foxes do not live on archipelago.
From among carnivores in New Zealand mustelids live – descendants of ferrets, ermines and minks. They are mainly medium-sized animals (up to badger-sized ones), arboreal and ground-dwelling ones. One species had developed life in rivers and at the sea coast. The most unusual mustelid of the islands is taranga, the ecological analogue of moles, completely underground mammal adapted for burrowing. Among canids there are the kinds descending from feral domestic dogs and being analogues of wolves and foxes. Pack wolf-looking kinds, however, do not reach the size of continental wolf of Holarctic and are more similar to short-legged wolf of Japan. Cats are descendants of feral domestic cat; they are predators of small size inhabiting forests and bush.
Ungulates of Aotearoa descend mainly from feral domestic sheeps. They are rather diverse; the largest kind of them, taurovis, reaches the size of bull. Also in the New Zealand fauna there are descendants of various kinds of deer, including very large ones.
Pigs, descendants of feral domestic pigs, diverged to some kinds: one semi-aquatic form on North Island, forest-dwelling and mountain-dwelling ones on both islands, where each one forms separate subspecies.
Rodents belong exclusively to murid family (and to endemic families descended from it). They are descendants of introduced Polynesian, brown and black rats and house mice. They are very diverse: among them there are arboreal, ground-dwelling, underground and semi-aquatic forms. Lagomorphs, closely related to rodents, descend from rabbits and hares and also are rather numerous. Among rabbits the social species with expressed caste system had evolved.
The New Zealand birds express great variety; they are even more diverse, rather than before arrival of Europeans to these islands. It is mainly connected to appearing of numerous descendants of introduced species.
The relic penguin lives in the mountain rivers and lakes – it is one of the last representatives of this order on the Earth. Other aquatic and wading birds of New Zealand include herons, terns, gulls, cormorants, sandpipers and ducks (descendants of native and introduced species). In addition to ducks, on Aotearoa there are other representatives of anserine birds order, descended from introduced Canadian geese and black swans. Black swan is an ancestor of barocygnus – very large herbivorous bird from Chatham islands. Grebes are widespread birds of freshwater reservours. One of their species from Chatham islands inhabits sea waters. More typical sea birds settling at the coast of archipelago are tubenoses of several families, cormorants, gannets, terns, gulls and some species of penguigulls. Also in New Zealand divesparrows live; these ones are sea birds from passerine birds order, related to dippers. The most numerous colonies of sea birds are located on remote islands where there are no predators from among mammals.
Near water and in forests numerous rails live; as against to island species of human epoch, they do not lose ability to fly. The unique family of deinorallids (“awful rails”) includes one species – ruacapangi descended from native weka rail. These very large birds are active predators successfully competing to mammal.
Gallinaceous birds of New Zealand descend from introduced species, mainly from quails, pheasants and New World quails. Some of them are remarkable because of large size and bright plumage.
The falcon birds order is presented by one species of harrier, several kinds of hawks (which ancestors settled at archipelago from Australia only in Neocene) and several kinds of falcons, descendants of endemic species and Neocene migrants from Australia.
Other predatory birds of New Zealand are owls. Neocene species descend from native boobook owl and introduced little owl. In addition to true owls, but only after human extinction barn owls had penetrated to islands and had evolved to endemic species.
Representatives of such groups, as nightjars, woodpeckers and swifts, are completely absent. There are some species of cuckooes and halcyons. Pigeons descend from one native and the several introduced species – they are mainly forest-dwelling arboreal birds eating fruit and seeds. Parrots are rather numerous; they are presented at once by three families: true parrots, cockatoos and Nestoridae. They descend from few native parrots, and also from introduced species and the kinds settled on archipelago only after extinction of mankind. The majority of them represents typical parrots in shape and habit of life, but also there are some exceptions. On islands nocturnal parrot kept ability to flight had evolved. Some kinds replace woodpeckers, having adapted to feeding on insects taken from under bark. The largest parrot of Neocene New Zealand is eagle kea, the kea descendant turned to true bird of prey. Some parrots live on islets far from coast of main islands. So, on Chatham archipelago large ground-dwelling parrot lives.
Passerine birds are presented by the greatest number of species. Among them descendants of endemic family of New Zealand wrens are remarkable. Only one species of this family survived in human epoch, but in неоцене it had continued evolution and had given rise to several local species. A part of families of New Zealand birds is shared with Meganesia, Polynesia and partly Asia. These are Old World flycatchers (including close families, for example, monarch flycatchers, fantails and petroicas), honeyeaters, white-eyes, wagtails (in particular, pipits), sylviids and some other, descendants of local species and Neocene migrants. Swallows have reached islands independently in XX century.
Existence of such families, as larks, thrushes, starlings, accentors and bellmagpies in Neocene fauna of New Zealand is connected to human activity. Also numerous local finches and weaverbirds (descendants of house sparrow) belong to descendants of introduced species. Almost all corvids of archipelago are descendants of introduced rook: they gave the wide spectrum of species resembling corvids of “mainland”: ravens, jays, magpies and others. However, on North Island one kind of corvids descended from the kind migrated from Polynesia lives.
Due to soft climate overwhelming majority of kinds of birds of New Zealand is non-migrating. Only separate species make annual migrations. New Zealand is a place of wintering of some species of birds from northern areas of Asia and North America.
Reptiles of New Zealand belong exclusively to squamates order. Turtles and crocodiles are not present, as well as in human epoch. Rhynchocephalians (gatterias) not sustained pressure on the part of introduced species and became extinct. Lizards are presented by skink and gecko families. New Zealand lizards stem from native kinds. Among them there are both ground-dwelling and arboreal forms. The largest lizard of New Zealand is mouse-eating gecko reaching the length of 70 cm. In Neocene in New Zealand snakes appeared – they are descendants of low-specialized sea snakes of genus Laticauda, returned on land. The small number of their species makes endemic family of New Zealand snakes (Aotearophidae).
All New Zealand amphibians of Neocene epoch are descendants of Australian tree frogs Litoria, introduced by people. In conditions of humid and warm, but not a hot climate these amphibians had gave rise to the set of various species. Among them there are arboreal, aquatic and ground-dwelling forms, resembling by shape typical tree frogs, toads and true frogs. From Litoria the family of New Zealand false salamanders descends – as a matter of fact, they are “adult tadpoles” lost an adult stage. False salamanders are externally similar to caudates and caecilians (though there are also completely unique forms, such as Batrachogymnotus) and inhabit all landscapes of New Zealand. The majority of them represents not so large animals. The largest representative of family is neohanasaki.
Primitive native frogs of Leiopelmatidae family had strongly suffered from human activity and influence of introduced species and had not left descendants in Neocene.
A specific variety of freshwater fishes of Aotearoa is poor. They are mainly fishes of order Galaxiiformes and sleeper gobies, and also descendants of sea forms, for example, flouders, pipefishes and others. Descendants of introduced fishes – trouts and carps, tench, European perch and brown bullhead – also live in rivers. At the north of archipelago viviparous fishes live in the rivers – these are descendants of introduced guppy and swordtails.
Invertebrates of New Zealand are rather diverse. Insects have the greatest number of species: butterflies, beetles, orthopters and others. Ants are numerous; among them descendants of introduced species prevail. From descendants of other introduced insects it is important to note earwigs, dung beetles, blood-sucking bugs and descendants of crickets. Endemic wetas – New Zealand group of giant flightless orthopters – had disappeared on main islands and on the majority of islets near to their coast. These insects had remained only on separate small islets isolated reliably from penetration of ground mammal. Descendants of introduced European wasps form numerous colonies existing within several years. Spiders of New Zealand are presented by the great number of species. From among crustaceans decapods are numerous: crabs at the sea coast, in humid forests and in fresh water, shrimps in rivers and lakes. Crayfishes of family Parastacidae also live in rivers and lakes, including mountain areas. In humid climate ground gastropods prosper – snails and slugs descended from both native and introduced species. Numerous bivalves live in rivers and there are some species of freshwater sponges.
In caves of New Zealand isolated ecosystems presented of troglobiont invertebrates are developed. Among them there are cockroaches and crickets (including tiny relic wetas) more often, but there are also beetles and spiders, millipeds and snails. Colonies of bats are food suppliers for them; also these invertebrates eat the animals casually fallen in caves and died there.
The review is written by Simon, the forum member
|New Zealand, forest animals.|
|Hunter from Ao-Tea-Roa||New Zealand, large local animals - predators and herbivores. (not translated, Russian version only!)|
|Fishes, frogs and penguins||Inhabitants of freshwater reservoirs of New Zealand - lake and river.|
In Neocene North America had shifted a little because of expansion
of Atlantic ocean. North American litospheric plate was rotated a little on
the spot (northern edge in northwest direction, southern to southeast) therefore
land bridge to South America had become torn, and that landmass turned to island
continent again. But at the other end the continent merged with Eurasia that
has resulted in re-appearing of Beringian isthmus, for the first time from the
ending of ice age. In southwest of North America this “skew” has broken former
California away from continent, having transformed it to long narrow island
and having formed an abrupt rocky coast, and in northeast the part of former
islands of Canadian Arctic Archipelago had joined Greenland, having made this
large island even larger. Also Greenland became little bit closer to North Pole
and in northern extremity of island the polar climate with polar night and cold
snowy winter dominates.
After thawing of glaciers formed on the boundary of Holocene and Neocene, northern extremity of North American plate had “emerged”, having disburdened from enormous weight of glacier, and the part of islands of Canadian Arctic Archipelago had merged with each other.
In the south of continent Caribbean sea still exists, having islands of various sizes and separated from ocean by the chain of large islands. Some small islands known in human epoch had disappeared completely (for example, Florida Keys islands), and others united and turned larger due to volcanic activity and movement of small litospheric plates. Also in Caribbean sea new islands have appeared also. In addition, as a result of displacement of litospheric plate of North America, its narrow southern part, Central America, now is directed to waters of Caribbean sea, having made it even shallower. Due to abundance of shallow water areas water of Caribbean sea gets warm better, and it promotes prosperity of coastal fauna and flora. Ocean currents form slow whirlpool in Caribbean sea; the water mass of Caribbean sea is rather isolated from ocean by barrier of islands and underwater mountains.
In southeast of continent because of general climate warming and some increase of precipitation degree swamp territories have extended, especially closer to coast of Caribbean sea. The transition between land, freshwater marshes, saltwater marshes and sea in some places is rather blurred, and it is difficult to point, where the continent comes to an end and Caribbean sea begins. It is territory of domination of tropical climate with plentiful rains. As well as in human epoch, hurricanes and extensive flooding are usual here.
The east of North America is stable in geological sense: here from the north to the south the old ridge of Appalachian mountains stretches and there are no spots of tectonic activity. At the east of North America the typical temperate climate was established, but northern border of all climatic zones near to coast is a little bit displaced to the north. The reason of it is Gulf Stream which in Neocene flows almost in parallel to North American coast, pushed aside to the west by cold Antigulf Stream flowing from the north to the south along the European coast. The east and the west of North American continent are separated by long strip of open flat district – from tundra in the north to prairies in the centre of continent and to deserts in the south. Mountains are almost absent there, therefore the wind from Arctic ocean can reach Mexican plateau easily.
In the central part of continent the typical continental climate with expressed alternation of seasons – cold winter and humid summer – is established. The amount of precipitation is greatest at the east of the continent, is gradually reduced in the central part of continent, sharply falls at the site of land to the east from Rocky mountains, and then rises again at the coast of Pacific ocean.
On open spaces there are rivers and lakes. Some of them are deep enough; others exist only in spring and in summer, during rain season. Because of non-uniform distribution of precipitation the large rivers flow only at the east of North America where in historical time the Mississipi basin was located. Meandering on plains, rivers change the location of channels as millennia pass, but run into gulf of Mexico, forming deltas with set of islets. Rivers from eastern slopes of Appalachian mountains reach Atlantic freely. Great Lakes of human epoch, large reservoirs of glacial origin, were gradually filled with deposits brought by rivers, and had turned at first to boggy plain, and then to dry district overgrown with forest. In ice age between Holocene and Neocene in various places of continent near the edges of ice sheet some large lakes existed, but they had gradually disappeared, having dried or having turned to bogs during ferst some millions years of early Neocene. At the west of North America rivers originate in Rocky mountains. Rivers from eastern slopes of Rocky mountains reach gulf of Mexico mainly in spring, when they are full of water. In summer they can dry up almost completely. To the north, in depth of continent, rivers from eastern slopes of Rocky mountains frequently end in small lakes or simply vanish in desert. The short rivers from the western slopes quickly reach Pacific ocean.
The majority of lakes of North America exists for rather short time – till some tens thousand years. The unique large and very old lake of North America is huge Mishe-Nama lake, former Hudson bay. During millions years glaciers and ocean combated for this place. Glaciers closed this place completely for many thousand years, destroying and superseding in rivers all live beings, but then at deviation of ice the ocean filled in this place again, bringing the sea fauna. But in due course the mouth of gulf had shoaled because of raising of litospheric plate and accumulation of glacial deposits, and in Neocene Hudson bay had shared the destiny of Baltic sea: it had turned to almost freshwater Mishe-Nama lake (salinity of about 1‰, and sometimes even less), but it has kept a part of descendants of sea fauna.
The northwest of Neocene North America is Beringia, a place where North America joined to Eurasia, having formed massive mountain ridge, which had cut off Arctic ocean from Pacific. In these mountains (and also in mountains of western North America and eastern Asia) the set of short and full of rapids mountain rivers flows; these rivers run into northern part of Pacific ocean, slightly freshening coastal waters. On flatland areas of north of the continent the set of lakes and marshes existing on the average only for some tens thousand years only is formed.
The North American coast of Pacific ocean has rather strongly changed in comparison with human epoch: along the coast of continent the new volcanic archipelago little bit similar to Kuriles is stretched. It is a result of fast movement of small Juan de Fuca litospheric plate along the American coast to the north.
To the southwest mountain ridges of Beringia are replaced by Rocky mountains. As well as in Holocene epoch, rather soft and humid climate dominates there. Mountain ridges block the way to the heart of continent to winds from Pacific ocean, and the significant amount of rains falls in narrow zone between coast and mountains, transforming short rivers to storming streams. The same mountains block way to cold winds from the north. Because of presence of Rocky mountains rain clouds do not penetrate far deep into continent, and along the mountain ridge “rainshadow deserts” stretch. In mountain areas earthquakes are often and there is a plenty of thermal springs. Some areas of mountain ridges in fact represent inactive volcanos.
Farther in southwest of continent coasts of North America turn abrupt and rocky again – it is a result of separating of California from mainland. In this area warmer water of top layer of ocean mixes up with colder water of depth, therefore in this place rains and fogs are usual.
Local ecosystem depends directly on rains and fogs which come from the sea, and farther to the south, where Mexican plateau rises above a zone of rainfall, the true desert is stretched, becoming a barrier to migration of southern species to the north. California island is also located in the zone of arid climate; its vegetation receives a significant part of moisture from fogs. Farther to the south, where there is Yucatan peninsula, climate becomes warm and very humid again.
The review is written at participation of Bhut, the forum member.
The North American continent evidently shows change of types
of vegetation in latitudal direction. At the north of the continent Greenland
represents an empire of polar climate and of the appropriate type of vegetation.
In northern extremity of Greenland the glacial cover was kept, around of which
there is a zone of tundra vegetation – evergreen undershrubs and grassy plants,
and also dwarf creeping trees. To the south of it there is an area of dry northern
meadows formed by sedges and graminoids. As well as in Eurasia, in North America
the areas, where perpetually frozen soil was kept, almost did not remain; Greenland
became an original “reserve” for this phenomenon, but also here the influence
of warm Gulf Stream removes area of permafrost farther from coast.
On islands of the Canadian archipelago in coastal areas cold northern bogs with the appropriate type of vegetation are widespread, and on heights forests of hardy and cold-resistant coniferous trees grow. At the significant part of coasts there is a littoral zone with thickets of large brown macroalgae. They expand especially plentifully along the Atlantic coast of continent, where warm Gulf Stream keeps the necessary temperature and interferes with freezing of sea. Extensive thickets of brown algae are widespread also at Pacific coast of North America.
To the south the zone of coniferous woods is stretched. In North America there is lesser number of large herbivorous mammals, than in Asia, therefore forests have more homogeneous structure and there are less embedments of deciduous trees in them. Deciduous trees grow mainly along riverbanks and near bogs, where ground is too damp for growth of conifers.
The zone of mixed and deciduous forests is very narrow in northwest of continent – the influence of Rocky mountains ridge forming “rain shadow” and interfering the penetration of rains from Pacific ocean deep into continent has an effect. Here most cold-resistant species of trees grow. In direction from northwest to the east and southeast the zone of deciduous forests extends. The coast of Mishe-Nama lake is surrounded with mixed forests with prevalence of deciduous species – its water mass softens a little and smoothens climatic conditions in its vicinities, and also creates the increased humidity of air favorable for development of grassy plants. Coast of Mishe-Nama lake is overgrown with reeds forming impassable thickets.
The original type of vegetation develops at Pacific coast, in narrow zone between Rocky mountains and the ocean. Here a plenty of precipitation and equable climate promote formation of true northern “jungle” – forests made of more thermophilic species of trees, rather than trees growing beyond the mountains. Tsuga, fir, spruce, and from among deciduous trees – various kinds of maples and poplars grow here. On large trees epiphytic mosses and ferns develop plentifully, and the vegetation of underbrush is presented by bushes and not numerous grassy plants. Forests of such type can grow only under protection of mountains which cover them from cold northern winds. Farther on south where mountains are not such abrupt, and their east slopes are more open, climate is much drier and moderate, and winters are colder, than in territory of former British Columbia. Here rarefied forests of deciduous kinds of oaks grow, being gradually replacing by bushes (scrub).
Along ridges of Rocky mountains the zone of plains lack of wood vegetation is stretched. These are North American prairies, places of growth of numerous kinds of graminoids and grassy plants of other families. In spring prairies have bright colours when perennial rhizomatic or bulb ephemeroids begin to blossom, but to summer brightness of colours is replaced by variety of shades of greens of graminoids. In southwest of continent between mountains and prairies there are areas of semideserts and dry fruitless deserts where only not numerous kinds of drought-resistant grasses, and also succulent plants grow. In valleys of rivers periodically filled with water, light prickly forests of desert treelike plants are formed – mainly of cactuses and treelike descendants of some grassy plants.
Rocky mountains show typical altitudinal zonation: near glaciers at their tops there are plants of tundra type, below them the zone of the Alpine meadows with diverse species composition stretches, and it is replaced by coniferous forests. In moderate latitudes in foothills the mixed and deciduous forests grow, and in subtropics and tropics there are chapparal and even evergreen forests.
Appalachian mountains are old mountains at the east of the continent. They are not so high, and altitudinal zonation is expressed not so clearly here. Slopes of Appalachian mountains are covered with broadleaf forests made mainly of maples, nut tree, plane tree, linden and chestnut. Higher in mountains oaks of various species grow. Also oak groves are characteristic for plain forests, especially in area of warm-moderate climate with sufficient humidifying. In southeast of the continent thermophilic plants appear in flora: cypresses, magnolias and palm trees. In some places of southern deciduous forests relic populations of ginkgo are kept; this is a doubtless descendant of trees cultivated by people. Grassy plants of southeast of North America are diverse, in flora of the south of Florida there are some forms descended from plants cultivated as ornamental ones (gladioli, begonias). Here also various marsh plants grow, including insectivorous plants of Sarraceniaceae family (pitcher plants).
In valleys of rivers of southern part of North America the moistureloving species of trees grow; they can resist flooding within several weeks during overflows and inundations.
Mexican plateau is the native land to various succulent plants, mainly to agaves and cactuses. Among cactuses frequently there are treelike forms, but the majority of their species represent small plants with non-lignifying stalks. Also in deserts numerous ephemers and ephemeroids grow, many of which have bright flowers (mainly representatives of Amaryllidaceae family).
To the south of Mexican plateau the area of forests of various types begins; they range from light forests formed of evergreen trees, up to true tropical rainforests in southern part of Central America, along northern coast of Panama passage. Lianes and epiphytes are numerous here, and there are hundreds species of trees at one hectare – two next trees of the same species can grow in several hundreds meters from each other. Forest canopy is linked as a whole by lianes, and the main biomass of such forest is concentrated at the height of several tens meters. Cactuses of genus Hylocereus and related forms of forest-dwelling cactuses are characteristic grassy plants of tropical forests.
For southern part of North America bromeliad family is typical; its representatives are widespread up to northern border of subtropical zone. At northern borders of the area they are mainly epiphytic plants, but in tropical areas among them there are also large ground species. Some species of them are a part of structure of Alpine plant communities.
The fauna of North America belongs entirely to Holarctic realm
(Nearctic section of Holarctic). Nevertheless, the significant influence of
Neotropic realm, to which the territory of South America belongs, is appreciable
Among mammals there are some groups of Neotropic origins; marsupials represent one of them. Despite of poverty of species composition, North American marsupials are not at the edge of extinction. In human epoch on the continent there was only one species of opossums, which has received significant advantages in survival due to ability to coexist people. Neocene marsupials are more diverse – they occupy various ecological niches and are widespread much wider, than in Holocene. Marsupial hyena, the large terrestrial species of marsupials, lives in deserts at the south of continent, and geopossum, another ground-dwelling species, lives in subpolar areas at the north of the continent, on islands of Canadian Arctic Archipelago and in Greenland. Ground opossums also live in forests at the east of the continent, but tree-climbing species are more usual; some of them have a little changed in comparison with the ancestor from human epoch.
Moles of typical shape are usual in forests and on plains of continent; in Neocene among moles Condylutra, large semi-aquatic species, had evolved. Hedgehogs are still not present in North America, despite of presence of Beringian isthmus. Shrews are usual and diverse. During the ice age at the boundary of Holocene and Neocene some of their species had penetrated through Florida to islands of Caribbean sea. At Pacific coast of North America there are some kinds of endemic family of jumping shrews – tiny zoophagous mammals. Other representatives of this family inhabit deserts and prairies of continent.
North America is the native land of last representatives of horse family. Having evolved first on this continent, horses had left the ancestral home and had returned again to New World only due to human activity. Asinohippus, the descendant of feral donkeys, lives in prairies and semideserts of North America.
Bovids of North America had died out gradually, superseded by other animals. In Neocene peccary descendants reached a significant variety and occupy various ecological niches. One species reached the huge size and became an ecological analogue of bisons. Related forms became omnivorous doubles of wild boars in forests of moderate and cold climate. Among peccaries of North America there are also semi-aquatic herbivorous forms living in swamps of southeast of the continent, and one species of unspecialized scavengers, the analogue of predatory boars of Eurasia.
Another ungulates also adjoin peccaries. Running deer rapidocervuses live in prairies; some of their species have gracile constitution like gazelles and inhabit semidesertic areas of continent. At the north of the continent in polar areas skewhorn lives; it is a specialized descendant of raindeer adapted for life in conditions of cold climate.
The existing of umingmak, the unique representative of titanolagids in America, at the northwest and north of the continent, is a result of connection of Old and New World via Beringian isthmus. Harelopes have not penetrated into North America.
Edentates are typical group of mammals of New World. Descendants of nine-banded armadillo are widespread to the north from Mexican plateau, occupying various ecological niches, up to semi-aquatic forms at the southeast of North America. In the north of an area North American armadillos run into hibernation. To the south of Mexican plateau, in forests of Central America, armadillos are usual and diverse.
The fauna of rodents of North America represents the result of freakish mixture of Holarctic and Neotropical faunae. Various squirrels, chipmunks, susliks and marmots, and also mice and rats, including the species introduced by people, represent the Holarctic element of fauna of rodents. Hamsters (including mouse-like ones) and gophers are diverse. Some North American rodents have reached the huge size – descendants of North American porcupines turned to ground-dwelling ones and settled throughout at the continent, from Mexican plateau to Greenland, having formed some species differing in size and ecology. The niche of aquatic predators at the south of continent is occupied by Neoichthyomys species – large aquatic rodents, the analogues of freshwater and sea otters. They are more diverse in Neotropic realm, and northern border of their area passes to the south of Mexican plateau. Caribbean sea is northern border of area of original order of algocetids, aquatic herbivorous mammals also of South American origin. The genus of deermaras, closely related to South American forms represents an element of South American fauna among cursorial grazers. These animals had settled to the north using the Antilles land bridge and have occupied an ecological niche of antelopes and pronghorns in prairie ecosystem. On islands of Caribbean sea related forms live. Continental deermaras inhabit prairies and semidesertic areas of continent, and also deserts of Mexican plateau.
Predators of North America belong mainly to felid, canid, raccoon and mustelid families. Among the largest carnivores there are berls – representatives of the group of predators common for Holarctic. Mustelids occupy an ecological niche of aquatic predators in areas of moderate and cold climate, and also are small and medium-sized arboreal and ground-dwelling predators. At the east of the continent ground-dwelling omnivorous mustelids (of “badger” type) are partly superseded by ground-dwelling opossums. Many canids of North America are descendants of coyote and grey fox lived in human epoch. Canids have reached a variety in forests and on plains, and among them there are specialized forms (lupardus). At the north waheela lives – it is a descendant of polar fox, a common species for Eurasia and North America. Raccoons are widespread and diverse mainly in southern and southeast parts of North America, as a part of thermophilous fauna; at the north only few species live. Arboreal forms of predators are presented by specialized family of raccoon lemuroids partly replacing primates in tropics of south and southeast of North America.
In Neocene primates live in territory of North America, but they are descendants not of New World monkeys of Neotropic realm, but of green monkeys introduced in human epoch to islands of Caribbean sea. After the formation of Antillean land bridge descendants of these monkeys settled to southeast part of North America and had formed some species in Florida. Rivers prevent the settling of narrow-nosed monkeys to the west and their appearance in tropical areas of Central America.
The fauna of birds of North America is diverse and rich, and it shows obvious similarity to fauna of Eurasia. Sea birds from northern coast of North America and Eurasia are similar to each other, and the part of species winters in common on islands of Pacific ocean. On islands of Canadian Arctic Archipelago gannetwhales rise their posterity; during their migrations they frequently come into shallow bays and feed in schools of fishes moving to rivers for spawning. At the Atlantic coast of continent it is possible to find plesioloons nesting on islands in the centre of Atlantic.
Pacific coast is a nesting place for numerous colonies of sea birds: auks, geese and ducks, and also for flightless algae-eating teratanatids. Gulls are usual at the coasts of all oceans washing continent; at the Atlantic coast large carnivorous griffon skuas live.
On Mishe-Nama lake the complex of bird species of sea origin is developed: dwarf species of gannetwhales, gulls, sea eagleravens and small species of auks.
Predatory corvids live at the coast of Arctic ocean (the species common with Eurasia), in coniferous and mixed forests (separate North American forms). On plains there are no analogues the Euroasian steppe species of eagleravens, because in Nearctic they are replaced by flightless cathartids. In general cathartids represent a characteristic group of predatory birds of New World, especially richly developed in South America. Alongside with flightless species, at the territory of North America some species of cathartids of more typical shape live: in forests of Appalachian mountains, in Rocky mountains, in Florida and at the southern coast of North America and in forests of Central America.
Among owls of North America (2 families: true owls and barn owls) the majority of species has typical “owl” appearance and habit of life. In Alaska and at the Pacific coast the large species, valkyrie owl, lives. Semideserts of the south are homeland for very large flightless prairie groundowl.
Among birds of marshlands and plains the crail family, common with Palearctic, is characteristic. It includes some species related to each other and differing in appearance. Via Greenland these birds had occupied islands of Atlantic ocean. Also for wetlands of North America herons of various species and rails are characteristic; some herons inhabit open spaces and semideserts. Rails reach an especial variety in marshy areas of southeast of continent and in valleys of large rivers. In tropical swamps of Central America there are some species of storks and ibises.
Gallinaceous birds of North America are various and widespread throughout the continent. Various galliforms on plains belong to tetraonid (sub)family. Also tetraonid birds inhabit forests at the north and northwest of continent. Populations of polar forms (descendants of willow ptarmigan) are widespread in Greenland and on islands of Canadian Arctic Archipelago. In semideserts and deserts of southwest of continent, including Mexican plateau, large flightless turkey descendant adapted to fast run and occupying an ecological niche of ratite birds lives. Turkeys also live in Central America and in southeast of North America. Phasianid birds (in restricted sense of this name) in North America are replaced by New World quails. Various kinds of these birds grow to weight from 150 – 200 g up to 2 kg and are found in forests and light forests of moderate zone, in forests of Appalachian mountains, in warm forests at the coast of gulf of Mexico, and also in Central America and Florida.
Among pigeons of North America the variety remained approximately at the level of human epoch. Some endemic species had evolved, including ones living on California island and in Florida. The greatest variety of pigeons takes place in forests of Central America.
Woodpeckers are widespread in forested areas of continent; the greatest diversity is typical for southeast of continent, in area of subtropical broadleaf forests. Northern kinds move to the south along ridges of Rocky mountains.
Variety of parrots in Neocene of North America is considerably richier, rather than in human epoch. In forested areas at the east of the continent some migrating species of parakeets of clear South American origin are widespread. Some parakeets live in deserts of Mexican plateau. In Central America parrots are considerably more diverse.
Hummingbirds are characteristic group of birds of New World. In North America there are some migrating kinds, one of which reaches Alaska. Some migrating species live at the east of North America, especially in river valleys. To the south from Mexican plateau and in Florida some settled species live. Swifts are especially diverse in Central America, and at the significant part of continent only some migrating species live. One species of swifts crosses Arctic circle and in northern summer nests in Greenland and on islands of Canadian Arctic Archipelago.
Passerine birds are still the most diverse order of birds, including in North America. General climate warming had allowed to some groups of Neotropical origin to settle widely on continent. In northern areas of continent finches, wagtails, titmouses, buntings, nuthatches and various corvids are usual. To the south the representatives of more thermophilous families appear – tyrant flycatchers, New World warblers, tanagers and grackles. Also from the north to the south species diversity of birds increases. An element of human influence to avifauna of North America is a presence of representatives of starling family, descending from European starling introduced by people. Their variety is insignificant due to competition of grackles. Other descendants of non-native birds are American weaverbirds, descendants of house sparrows. They live mainly in light forests of the central part of North America, to the east of area of prairies.
Among reptiles of Nearctic lizards of Teiidae family (mostly ground-dwelling forms) are the most widespread and usual. At the south of the continent the representatives of iguanids appear (mainly arboreal forms). In plain and forest areas in zones of temperate and subtropical climate slow worms (Anguidae) are usual, and to the south skinks and not numerous geckos live. Poisonous lizards of endemic helodermatid family grow to great size and belong to the number of top predators of desert ecosystems; there are also some small species of helodermatids.
Snakes of North America belong to colubrid, adder and elapid families. To the south of Mexican plateau boas live in tropical forests.
There are no crocodiles and alligators in territory of North America in Neocene. Freshwater turtles of North America belong to several families. The representative of snapping turtle family is very large trapperturtle – the heavy-built reptile being an ecological analogue of crocodiles hunting ground mammals and large birds. Small turtles also are numerous and diverse. Soft-shelled turtles are very small and inhabit only the south of continent.
Caudate amphibians are very diverse and have settled far to the south. Representatives of Cryptobranchidae family had died out, but their place is occupied by large representatives of Salamandridae family. Serpentina, large Greenland amphibian, lives to the north from Arctic circle. Various salamanders and ambystomas live in humid forests along the Pacific coast. To the south the variety of caudate amphibians declines, but in territory of Florida many kinds of dwarf salamanders are found. In rivers of temperate zone representatives of Sirenidae family are widespread. Among caudate amphibians there are some neotenic forms, mainly mountain- and cave-dwelling ones. Anurans of Nearctic are presented by true frogs, toads and tree frogs. Also some representatives of leptodactylid frogs live in Central America.
Fishes of northern part of North America are close to Asian ones. Pikes, a small number of salmon fishes and smelts are characteristic. In temperate zone also freshwater sticklebacks and allied forms live. Cyprinid fishes of North America are presented by descendants of carp introduced by people and farmed commercially, and also by small number of local genera of small fishes. A variety of suckers (Catostomidae) is less, rather than in human epoch – it is connected to extinction of many species of these fishes in epoch of anthropogenous pressure. However, among few survived kinds of suckers there is a giant herbivorous species. In Neocene fauna of North America characinids are usual; they are descendants of Mexican tetra (Astyanax) settled to the north after the ending of an ice age on the boundary of Holocene and Neocene. In comparison with Neotropical characoids North American kinds are less diverse. To the south of Mexican plateau, in reservoirs of Central America, numerous characoid fishes live. Catfishes of native fauna are presented by the various kinds of ictalurid catfishes varying in size from giants up to 2 meters long down to dwarfs about 10 cm long. In Florida there are descendants of loricariid (suckermouth) and clariid catfishes introduced by people. Central American catfishes are little bit more diverse, among them there are loricariids and a small number of non-parasitic pencil catfishes (Trichomycteridae). In river mouths ariid catfishes live, and one large kind of this family inhabits Caribbean sea.
From the order of percoid fishes sunfishes (basses, crappies, etc.) and percids (perches, etc.) are characteristic. At the south of the continent cichlids are diverse; the part of them represents the descendants of fishes lived in natural conditions in Central America. In a separation from the general area of cichlids some species of this family live in rivers of Florida and on islands of Caribbean sea – they are descendants of cichlids introduced by people. Various viviparous fishes are characteristic inhabitants of Central America and southern part of North America. They are especially numerous to the south of Mexican plateau, where the influence of Neotropical realm has stronger effect. Here, in Caribbean sea basin, there is a centre of variety of this group and some families of viviparous fishes had evolved. Among viviparous fishes the specialized forms evolved – predators, phytophags, filter-feeding phytoplankton consumers. In coastal waters there are specialized representatives of head-standing live-bearer family, living both in sea, and in fresh water. Among other fishes of southern part of the continent sharks and rays coming into fresh water, and also flounders and pufferfishes are characteristic.
Among invertebrates of North America various insects similar to species of Eurasia (especially at the northwest of continent) are characteristic. The fauna of insects of the south and southeast of continent includes a plenty of species of subtropical and tropical origin. Among freshwater crustaceans representatives of Cambaridae family are characteristic. Freshwater shrimps live in rivers of southern and southeast part of North America, and in swamps and river mouths there are crabs, including ones only temporarily living in fresh water. The significant number of fresh-water descendants of sea crustaceans and molluscs is typical for Mishe-Nama lake. Humid forests of Pacific coast of North America are inhabited by numerous kinds of snails and slugs frequently reaching large size. Freshwater snails of Ampullariidae family (apple snails) live in Central America.
|Desert of Mexican plateau, predators and herbivores|
|Plains of central part of North America|
|Greenland, plains. (not translated, Russian version only!)|
|Small inhabitants of humid subtropical forest of Pacific coast of North America. (not translated, Russian version only!)|
|The home of Green Feather||North-East of North America, mixed forest in temperate climatic zone. (not translated, Russian version only!)|
|Forest and sea||Mangrove forests of Florida, aquatic and forest animals. (not translated, Russian version only!)|
|Secret links||Mangrove forests of Florida, parasites of local inhabitants. (not translated, Russian version only!)|
|Decline of the dynasty||North America, Cascade Mountains - large herbivores and predators. (not translated, Russian version only!)|
In Neocene South America separated from North America, and
isthmus of Panama no long exists – it ia had taken place as a result of expansion
of Atlantic ocean. This continent is formed to two lithospheric plates – South
American (forming the most part of the territory of continent) and Nazca (located
under water of Pacific ocean and slowly moving down under South American plate).
The connection of North and South America is influenced with movement of two
small lithospheric plates in Central America – Cocos plate forming a significant
part of isthmus of Panama, and Caribbean plate carrying the largest islands
of Central America and forming a bottom of Caribbean sea. Small Scotia plate,
which borders are marked by several subantarctic islands, adjoins to the far
south of South America.
In Neocene South American continent had moved to southwest, but in general its geography has remained quite recognizeable, despite of time passed from the ending of human epoch. The significant part of continent represents flatland area with not numerous old mountains undergone to deep erosion, and only in the west the high ridge of Andes – young and tectonically active mountains – stretches. Volcanos erupt here, and mountains gradually rise and in Neocene their average height is more, rather than in human epoch. It takes place due to movement of litosperic plates – Nazca plate is subducting under South American one, forming deep Peruvian trench, and it is a principal cause of volcanic activity in Andes.
In the north still there is small Guiana Shield, but it is strongly eroded now. In eastern part of continent larger Brazilian Highlands are a watershed between two largest river systems of continent.
To the north of Brazilian Highlands there is a large river basin, which was earlier an Amazon river basin. This district is made of easily washing away river deposits from Andes, and rivers constantly change the current. In Neocene Amazon, the deepest river of South America, turned much smaller because of division of its basin. Northern part of Amazon basin now forms the separate Hyppolithe river. Both rivers finish their way to ocean approximately at the same area of coast, where the extensive marshy delta is formed, penetrating far to the sea. Between basins of these rivers there is an unsteady watershed combined of easily washing away deposits, therefore from time to time between Amazon and Hyppolithe the water exchange is formed, resulting in mixture of faunae of aquatic animals. To the south of Brazilian Highlands the Parana basin is located. It does not contact with basins of Amazon and Hyppolithe.
At the west of South Americas there is little number of rivers, and they are very short. At the significant part of Pacific coast of the South Americas rivers flowing down from mountains terminate in deserts at the mountain bottom.
In South America there is a plenty of lakes, but all of them are young enough and rather small in size. These lakes represent former sites of river channels, which are filled fast (in geological sense) with deposits, turn to marshes and disappear completely. Numerous lakes in Andes also exist rather not for long. The exception is the highland Totora lake located on Altiplano plateau. This lake of glacial origin, the largest in South America, was significantly “rejuvenated” by glaciers destroyed Titicaca lake existed at this place and than raked off layers of deposits from Altiplano plateau.
Extensive swampland areas exist on the north of the continent, in Amazon and Hyppolithe basins, and also in far south of Patagonia and on Tierra del Fuego.
Areas of dry plains stretch in Parana basin and farther in the south, in Patagonia. The formation of such areas is promoted entirely by mountain circuit of Andes forming “rain shadow” areas, blocking a way to rain clouds from Pacific ocean. To the west from Andes the narrow zone of land is stretched, where the humid and cool climate is replaced by hot and arid one from the south to the north.
South America is surrounded with a plenty of islands. At the north of the continent the largest islands are Trinidad and islands of Lesser Antilles. To the west from the continent Galapagos islands are located, which area had appreciably increased due to volcanic activity. But the greatest number of islands is located in a southern part of continent. In Pacific ocean these are Juan Fernandez archipelago and numerous islands along the western coast of continent. In Atlantic islands are not numerous, and only in far south there are Falkland. In the south of the continent Tierra del Fuego archipelago still exists, and also many volcanic islands have appeared in Drake Strait – it is a trace of moving of Antarctica aside Meganesia.
In connection with moving of the continent climatic zones have shifted from the south to the north, but it is substantially compensated by the general climate warming in Neocene. At north of the continent conditions are humid and hot, like in human epoch – the equatorial climate dominates here. The far south of the continent, on the contrary, differs in seasonal and moderately cold climate. Summer became hotter here, rather than in human epoch – it happened due to shifting of Antarctica from polar position. But heat is combined with high humidity of air formed because of prevalence of western winds. In winter at the south of continent snow falls and stable snow cover is kept for some weeks, but there are no nipping frosts.
On the territory of South America there are two floristic kingdoms
– Neotropical and Holantarctic. The border between them is determined by relief:
along mountain areas cold-resistant southern species settle farther to the north.
In Neocene significant territories of South America are covered with forests. It concerns mainly to northern areas of continent, to area of equatorial climate. Here areas of tropical rainforests (selva) are broken only by rivers flowing through them. Tropical rainforests differ in highest species diversity – two trees of the same species may be separated by tens, and even by hundreds meters of continuous forests. Sterculiaceae, Lecythidaceae and Fabaceae (bean family), and also palms are characteristic families of plants here. In flora of the north of South America there is less number of representatives of ancient, relic families though there are kinds of such families, as Annonaceae, laurels and myrtles. Some groups of trees are rather young from the evolutionary point of view (for example, treelike Asteraceae) – it is a sign of former degradation of forests in human epoch and of later restoration of specific variety due to occurrence of new taxa. In ice age at the boundary of Holocene and Neocene the forested area was the least – they remained only as small sites in rivers valleys, whence further restoration of large forests began.
Tropical rainforests are remarkable in variety of lianes and epiphytes. Among epiphytic plants orchids, aroids, begonias, ferns and mosses are characteristic. Many epiphytes belong to bromeliad family, characteristic for South American flora. One more group of epiphytes unique for South American selva includes forest-dwelling cactuses (Hylocereinae tribe and mistletoe cacti). Among aroids there are many lianes, including large ones, and also there are very large perennial ground grasses. Also Bignoniaceae (trumpet creepers), well appreciable due to large flowers of bright color belong to the number of lianes. Grassy plants of tropical rainforest include representatives of families Araceae (aroids), Marantaceae (arrowroots), Cannaceae (cannas), Gesneriaceae, Solanaceae and many others. Endemic families are Tropaeolaceae, including various kinds of grassy plants, and Cannaceae – perennial rhizomatic grasses. Among trees and grassy plants there are many myrmecophilic kinds forming cavities in stalks and/or edible formations on leaves to attract ants protecting these plants from herbivorus insects. In rivers of equatorial area flowering aquatic plants are richly presented – Alismataceae (various Echinodorus species), water lilies, including large ones, and also Pontederiaceae (water hyacinth kept from human epoch).
Small areas of tropical light forests grow on Guiana Shield.
To the south there is an area of tropical light forests where palm trees, treelike Cereus cactuses and some kinds of trees of bean family dominate. Such type of vegetation prevails on Brazilian Highlands, alternating with areas of dense forests and bushes in river valleys. On sunny dry slopes araucarias grow. Elements of southern flora begin to appear here: araucaria forests grow on highest areas of Highlands; also there are thickets uf Nothofagus there.
The area of tropical savannas in South America differs from extensive forestless spaces of northern hemisphere. Here, in Parana basin, on savanna the rivers flow, originating in Andes and on Brazilian Highlands. Along the rivers cactuses, reaching large size, and also palm trees grow. In areas of seasonal precipitation, far from large rivers, grassy plants – various graminoids and forbs – expand. For these places Amaryllidaceae, going through drought as underground bulbs, are characteristic. Also in savanna large single bromeliads and agaves grow, representing the analogues of African aloes. Because of shifting of continent to the south the area of dry grasslands and semideserts is larger, than in human epoch, and the area of more humid pampas reduced down to small site to the south of Brazilian Highlands. The rivers of Parana basin, originating in mountains, soften conditions of life in dry grasslands, enabling to trees to grow.
After dry grasslands the area occupied by forests of warm-temperate climate has extended. Extensive forest areas have appeared in Patagonia. Here araucarias and Nothofagus dominate with an addition of some other plants (for example, fuchsia tree and many species of bushes). Due to climate warming some kinds of palm trees settle far to the south, reaching the area of short-term winter frosts. Cactuses also settle to the south, and even farther, than palm trees. Some small cactuses can even winter under snow.
The far south of continent is an area of seasonal climate with cold snowy winter. Deciduous trees and cold-resistant araucarias, and also evergreen bushes, capable to winter under snow, grow here. They form multileveled forests with rich underbrush.
The mountain chain of Andes precisely expresses the phenomenon of altitudinal zonation. In equatorial area (Northern Andes) as the height above sea level grows, tropical forest is replaced by semi-deciduous forests, where bushes and bamboo dominate. The area of paramos– the xerophytic vegetation community – is stretched higher. And closer to tops, up to borders of eternal snows, there is a zone of vegetation similar on tundra – evergreen perennial grasses able to endure severe cold. In Central Andes instead of paramos there is puna – a complex of vegetation where drought-resistant grasses (graminoids and sedges) dominate. Such vegetation is characteristic for Altiplano plateau and for other Alpine areas. Characteristic representatives of Alpine flora are the cactuses covered with white “wool” and in equatorial latitudes also agaves and large bromeliads having wax cover on leaves. In Southern Andes araucaria forests grow with an addition of Nothofagus and bushes, and with fern underbrush. Above them the area of undersized grasses and creeping evergreen bushes is located, and at the edge of glaciers peat bogs are usual. Sundews are characteristic plants of these places.
Fauna of South America belongs to Neotropical zoogeographic
Within several millions years North and South America were connected by isthmus of Panama, which allowed to Nearctic and Neotropical realms to exchange species of flora and fauna freely. This isthmus existed for some millions years during early Neocene, but later the connection had been interrupted as a result of movement of Cocos tectonic plate from the side of Pacific ocean and expansion of Atlantic. The connection between North and South America was supported for some time due to existence of Antilles island bridge, and some species of North American fauna (mainly birds) managed to settle by such way to South America (in opposite direction using the Antilles bridge not only birds, but also various mammal had penetrated to the north).
The mammal fauna of South America at the level of families keeps approximately the same structure, as in human epoch, though new groups – families and even orders – have evolved.
Marsupials prosper, though their variety kept about same, as in human epoch. Among marsupials two groups dominate: opossums and shrew opossums; besides there are some families descended from opossums, for example, American marten opossums. Marsupials are widespread everywhere in South America and live also in cold high mountain areas and on Tierra del Fuego, in conditions of seasonal climate with cool rainy summer and cold snowy winter. The majority of marsupials belongs to insectivorous or omnivorous species, but there are predatory arboreal forms (American marten opossums), actively hunting smaller vertebrates in selva and in mountain forests. Shrew opossums, as well as in human epoch, are analogues of placental shrews, but among them one kind eating parasitic invertebrates in wool of large mammals had evolved.
Due to warm climate in significant part of territory of South America chiropterans prosper. Among them predatory, insectivorous and plant-eating species exist. Very small nectar-eating species are found in tropical woods. On plains the kinds eating blood-sucking insects live, gathering around of herds of large herbivorus mammals.
The variety of edentate order characteristic for Neotropical realm was considerably reduced at the border of Holocene and Neocene. Sloths and anteaters had died out because of changes of environment – reduction of the area of forests and degradation of grasslands. Only armadillos had kept a certain variety in transitional period, and it had allowed to be kept to some of the most widespread species which became ancestors of Neocene forms. In Neocene among them some specialized kinds had evolved. Some insect-eating armadillos partly occupy an ecological niche of anteaters; large forms of scavenging armadillos had appeared. There is also a burrowing armadillo – the analogue of moles.
Insectivorous are almost not present in Neotropical fauna of Neocene: only on far north some kinds of shrews live. Moles do not live in South America.
Significant changes had taken place in primate order. In New World in human epoch primates were presented exclusively by representatives of flat-nosed monkeys and were mostly arboreal animals. In Neocene many specialized arboreal groups had died out (for example, spider monkeys), and flat-nosed monkeys of Neocene epoch are descendants of small species – capuchin monkeys, squirrel monkeys and marmosets. Among them large forms spending a significant part of time on the ground had evolved: the part of flat-nosed monkeys had moved to the ground and turned to analogues of baboons (South American barbudo) and gorillas (mapinguari). OldWorld monkeys from Antilles had not settle to the continent.
Fauna of ungulates of South America is rather poor. It is connected mainly to low variety of this group in human epoch; to the end of human epoch the significant number of their species was at the edge of extinction. Nevertheless, among the largest herbivores of the continent there are tapirotheriums – descendants of relic tapirs, representatives of perissodactyls. The group as a whole is declining, but there are some species of tapirotheriums widespread in forests and on plains of continent. Artiodactyls are a little more diverse. These are representatives of peccary family – the kinds kept characteristic pig-like appearance and living in mountains, light forests and on plains.
Carnivorous mammals are representatives of mustelid, canid, felid and raccoon families, and also the related families evolved in Neocene. Mustelids represent mainly small forms and hunt rodents, but the family includes jagueira – very large and heavy-built species of mustelids, being an active predator. Among raccoons arboreal forms are usual, but one of their representatives is pampanasua, the ground-dwelling kind living in savannas. Arboreal forms of raccoons in early Neocene had given rise to separate family of South American tail-grippers, which representatives have convergent similarity to primates and partly replace them. Small cats (mainly descendants of domestic cats) are diverse and inhabit dense and light forests, and also mountains. Among felids there is a group of large species – raptor cats remarkable by especially advanced claws on hind legs. They are descendants of puma and large prey hunters. Canids of South America are various kinds of foxes and uctenas (coyote descendants). They inhabit mainly mountain areas, light forests and pampas. Some kinds of foxes live at the far south of the continent, in area of seasonal climate with cold winter.
Rodents of South America express great diversity. Their variety has increased from human epoch, but descendants of introduced rats and mice make very small part of the general variety of this group. Caviomorph rodents flourish and had considerably increased in size. Some of them (deermaras, barocavias, giant paca) became analogues of ungulates; possible, a low variety of local ungulates takes place because of their prosperity. Giant groundsloth rodents, very large forms from temperate latitudes of the continent, show the phenomenon of convergence with fossil chalicotheres and Neocene ndipinotheres. From arboreal species New World porcupines are usual; among them side-spined porcupine represents the anatomic and ecological analogue of sloths.
Rodents had developed aquatic habitats in full degree: otterodents are representatives of separate family Neoichthyomyidae. These are medium-sized and large aquatic forms inhabiting freshwater reservoirs and coastal sea waters. One of their species, ayapuh, lives at the far south of the continent, at the sea coasts.
Alongside with atypical rodents there is a plenty of small forms, mainly burrowing or arboreal.
In early Neocene from rodents (coypu) the separate order of algocetes descended; these are aquatic herbivorous mammals similar to manatees. Some algocetes inhabit fresh water, and other kinds are sea-dwelling. Falkland paralgocetus, the largest kind of this order, belongs to marine forms.
Birds of South America show a great species diversity that is connected to expansion of territories overgrown with forests. At the far south of continent there is a plenty of migrating species, including ones flying to North America and islands of Caribbean sea.
Various tinamous belong to the number of endemics of South America. Representatives of this order in fact did not settle away from the continent, and the attempts of their introduction in human epoch had failed as a result. In Neocene in territory of the continent very large ostrich-like species of tinamou lives. Nandus (Rhea) had died out upon the ending of human epoch, and tinamous, their close relatives, had replaced them.
Cathartids are very characteristic group of South American zoophagous birds. They turned to ecological analogues of griffon vultures and condors of human epoch, and some medium-sized species became active hunters for smaller birds. One of cathartid group members is acatou – the largest flying bird of the world living at the edge of ability to flight. Cathartids are related to stork birds, and some stork birds of Neocene are remarkable in the same predating habits. Large flightless hunting herons, hunting in small packs, are ecological analogues of wolves in grasslands of South America. The majority of herons and bitterns, however, leads more typical way of life: they inhabit reed thickets and flooding forests, and hunt fish, amphibians and invertebrates. Also in tropical, subtropical and mountain areas of continent ibises are widespread. Among waterfowl grebes are characteristic; they are especially numerous in mountain lakes in Andes, and also at the the south of the continent. Some of their species lack the ability to flight.
Gruiform birds are presented mainly by rails and descendants of seriemas; some of the latter became active predators, ecological analogues of secretary birds of Africa.
Predatory birds of falcon birds order are numerous species of caracaras, inhabiting mainly plains and light forests of continent. Some large kinds live in forested areas of continent. There are some kinds of true falcons, among which there is a wolf falcon having developed a semblance of social way of life.
Gallinaceous birds are presented by pheasant and New World quail families; Cracidae (curassows and allies) had died out in human epoch. Tinamous make a significant competition to galliforms, and representatives of New World quails occupy mainly bushes, light forests and underbrush of tropical forests. The pheasant family is presented by descendants of feral chicken of primitive native breeds.
Birds of anserine bird order reach the especial variety due to a plenty of habitats. Various kinds of ducks are widespread from tropical marshes at the north up to the far south of the continent and consume various kinds of food: from fish down to plankton crustaceans and algae. At the coast of continent in the zone of temperate climate sea swans are widespread; these are large algae-eating ducks.
Sandpipers live everywhere at sea coasts and on riverbanks. Some migrating kinds settle near temporary reservoirs in areas of seasonally droughty climate. Near mountain lakes some endemic local kinds live. Gulls and terns are widespread everywhere, in southern areas of continent there are representatives of penguigulls – the kaveskar genus including several species. The relic species of penguins still exists in South America in a unique place – in Totora lake.
Due to restoration and expansion of forested areas the variety of forest-dwelling birds is especially great.
Hoatzines endemic for South America have survived in human epoch, but their variety is not too great because of strict specialization. Some species of these leaf-eating birds live in forest canopy, partly replacing extinct cracids. Cuckooes related to them express the diversity and mainly raise posterity by themselves. Some of them build large common nests and raise nestlings in common.
Columbine birds of South America belong only to pigeon family and live mainly on plains, in mountain forests and in forests at the south of the continent. The part of their species descends from feral pigeons introduced by people.
Parrots are representatives of true parrot family only. All psittaciforms of South America are parakeets of various sizes, from small up to large ones. In human epoch the number and variety of parrots were reduced considerably, and almost all large parrots had become extinct or their number had reduced in great degree. Neocene parakeets descend from the small species kept in the rests of tropical forests and on Antilles. They are diverse and brightly coloured, and in Neocene it is possible to find parakeets in all territory of the continent. Some kinds descending from monk parakeet (Myiopsitta monachus) have developed areas of cold climate: snow parakeet lives in mountain areas, and some other kinds inhabit forests of far south of the continent and in the summer appear on Tierra del Fuego regularly.
Hummingbirds are characteristic group of birds of New World. Their number and variety were restored after changes in nature which have taken place at the boundary of Holocene and Neocene. From some unspecialized ancestors many unusual and freakish specialized kinds descended (for example, crook-bill hummingbirds bacororo and itubory). Wasp-mimic hummingbird from tropical rainforests of the north of the continent precisely imitates poisonous corsair wasps for protection against predators. In woodlands and mountain areas swifts are found.
The tropical trogon order has kept an enough variety in South America. The majority of trogon species represents small birds with long tails, but there are some raven-sized species. Their area is limited only to tropical rainforests, including Antilles.
Nightjars are especially diverse in plain areas, and live even in Alpine areas and in “rain shadow” deserts along the ridge of Andes. In tropical forests large nightjars live (potoos of their own family), which eat small vertebrates.
Owls belong to two families: true owls and barn owls. The area of barn owls is limited by tropical and warm-temperate areas of the continent, and true owls live in forests up to the south of continent, and also in mountain areas. Some owls nest on the ground, digging out holes or occupying holes of large rodents. On plains the small kind of owls eating insects lives, and in tropical forests there are the kinds specializing on hunting frogs and bats.
Coraciiform birds are presented by numerous halcyons living near rivers and lakes throughout the continent (in southern regions halcyons are migrating). Some of them have adapted to life in tropical forest canopy: bromeliad kingfisher catches tadpoles and insect larvae from leaf axils of epiphytic bromeliads.
Woodpeckers and alies are presented by various true woodpeckers, the part of which is related to kinds from Antilles. There are the separate specialized kinds eating social insects. There are not numerous kinds of other families of piciform birds – toucans, jacamars, puffbirds and American barbets.
Among passerine birds various Tyranni (American suboscines) of several families dominate: cotingas, ovenbirds, tapaculos, tyrant-flycatchers, antpittas and some others. They express the phenomenon of convergence with songbirds dominating on other continents. In epoch of global ecological crisis the great enough number of groups of these birds had survived, and it has allowed them in further to restore variety and to compete successfully to songbirds settled from the north. Among ovenbirds prairie pipebirds are interesting – these birds build massive thick-walled nests of clay on the ground. Tapaculos are common in southern part of the continent, preferring forestless areas; in the past the representatives of these birds were successfully settled to Antarctica. Cotingas inhabit tropical forests; their loud, frequently melodious, but monotonous calls represent the characteristic feature of tropical rainforests. From among songbirds in South America there are about twenty families, including tanagers, grackles, finches, vireos and others. The presence of weaverbirds (descendants of introduced house sparrow) in ornithofauna of South America is a result of human activity. In Neocene at the territory of South America the family of false swallows has appeared – these are small well flying insect-eating birds, preferring to live in cooler areas of continent. Some of their kinds migrate to Antarctica in summer.
Reptiles of South America are diverse and numerous due to a favorable climate of the most part of the continent. Here there are representatives of turtles, squamates and crocodile orders. Among turtles the majority of species is present by side-necked ones leading aquatic habit of life. Overwhelming majority of turtles represents small forms, but in basins of Amazon and Hyppolithe large kinds with carapace length of about 100 cm live. One of the largest kinds of turtles is elasmosaurine hydromedusa, very large fish-eating reptile with very long neck, almost constantly living in water. True tortoises are not numerous in South America in comparison with species of Old World; also there are some kinds descended from aquatic turtles and passed back to terrestrial habit of life.
Squamate reptiles are presented by several families of lizards and snakes. As well as in human epoch, iguanids represent the most widespread family; they are mainly arboreal, ground-dwelling and semi-aquatic forms. Very large aquatic lizard aquaguana eats exclusively hydrophytes and fruits dropping in water from trees. Another lizard family is teiids. It includes mainly the ground-dwelling forms living in arid areas and in the zone of temperate climate. Also in South America geckos, skinks and anguid lizards live.
Among snakes various boas are characteristic – from small arboreal ones, up to large ground-dwelling forms. Among poisonous snakes rattle snakes and related forms are most common. In tropical areas of continent blind snakes are widespread; this is a conservative group of small burrowing reptiles living in soil of tropical forests.
Ground-dwelling caimans, the representatives of declining order of crocodiles, are analogues of monitor lizards and inhabit pampas and light forests.
Due to humid climate the fauna of amphibians is very rich in South America. Caudates are richly presented in North America, but in South America they are absent. In South America anurans (toad, leptodactylid, arrow poison frog, tree frog families) are the most diverse, but there is a significant number of species of caecilians. Pipidae were kept in small amount in Parana basin. The majority of anurans lives in forest canopy, where their representatives express great variety of colors and sizes. Tiny arrow poison frogs are less various, than in human epoch, and belong to several undoubtfully differing genera. Among toads there are large poisonous forms and a plenty of small ones similar to arrow poison frogs in brightness of colouring and the small size. In Neocene some new groups of anurans have appeared. Branchial tadpole, the representative of neotenic frogs, is an irreversible neotenic amphibian, completely lost ability to turn to adult individual. It leads a parasitic way of life on gills of large fishes. Endemic family of spherical frogs comprises poisonous amphibians from tropical areas of the continent, capable to be inflated strongly.
Caecilians comprise burrowing and aquatic forms changed externally in a little degree from human epoch.
Fishes of South America show a variety comparable to those in human epoch. The significant part of kinds of fishes lives in rivers of Atlantic ocean basin; the ichthyofauna of rivers of the western part of continent differs in poverty and includes mainly fishes of sea origin.
In South America dipnoan fishes have kept – there is one kind of Lepidosiren in due course of evolution got an ability to form protective cocoon like African Protopterus. Aravanoid fishes have kept; large boltergillers are inhabitants of lakes and slowly flowing rivers, eating phyto- and zooplankton with the help of advanced branchial filtering system. There is also a small kind of zoophagous arowanas eating insects and small fish.
Among more progressive groups of fishes catfishes are diverse; among them there are parasitic forms (species from various families in Totora lake and in Amazon and Hyppolithe basin). Loricariid catfishes including many local species are most various. The representative of doradid catfishes, worm catfish, has passed to burrowing habit of life in damp wood litter. The unusual wattle-walking catfish (pimelodid (long-whiskered) catfish family) inhabits deep-water sites of rivers.
Characoid fishes are the most diverse group by number of species. Representatives of characoids vary from tiny harmless omnivorous kinds up to very large predators and occupy not only tropical reservoirs, but also cold mountain rivers and rivers of far south of South America. Their largest kind is Tyrannocharax hunting large vertebrates. The center of variety of characoid fishes is the northern part of the continent, where there are representatives of several families and numerous local species.
Gymnotids (knifefishes) widespread in tropical rivers and lakes are endemic group of fishes. They are predatory fishes with lengthened body, the size from small up to rather large, using electric field for prey searching and catching. Some gymnotids lead burrowing way of life on oozy bottom of rivers.
Viviparous fishes are presented by numerous small species similar to their ancestors of human epoch; they do not reach such sizes and variety, as in Central America and Caribbean sea. Some large species of viviparous fishes of Caribbean origin are found in rivers of northern part of South America. In the central and southern part of continent killifishes live – these are tiny fishes, living frequently no more than one season and surviving in drought season at the stage of resting eggs.
Needlefishes are fishes of marine origin. In rivers of northern part of South America there are some kinds of these fishes, but they are not completely fresh-water and move to sea water for spawning.
Cichlids were characteristic representatives of South American ichthyofauna in human epoch. In Neocene the variety of these fishes remained at the former level, but rough evolution of characids had superseded cichlids to another dimensional class: in Neocene they are mainly small, and even dwarf fishes.
Another percoid fishes of fresh waters of South America are gobies and croakers. They live in fresh water for a long time, but move to the sea for spawning. Among gobies there are some true freshwater species.
True soles, the representatives of flounder order, come into rivers of South America in areas of tropical and temperate climate. As well as all flounders, they spawn exclusively in sea water of sufficient salinity. At the far south of South America in fresh water vertical flatfishes (or non-angelfishes) live; it is an original group of flatfishes of Antarctic origin, which have kept vertical position of the body from larval stage.
Pufferfishes inhabit mainly rivers of tropical latitudes; they are exclusively small species. The part of them spends only a part of life cycle in fresh water, but there are also true freshwater species.
Cartilaginous fishes – rays and sharks – also live in South American rivers. In tropics they are presented by rays of river stingray family and some kinds from among whiptail stingrays. One representative of river stingrays lives in cold Alpine lake Totora.
Invertebrates express an exclusive variety, especially in tropical forests. Among insects very large beetles – capricorn beetles and scarabeids – are remarkable. They frequently have very long antennae or freakish outgrowths on head and prothorax. Fireflies are very characteristic beetles of tropical forests. Grasshoppers and locusts may grow very large and frequently distinguish in cryptic colouring and freakish body shape. Among cockroaches there are brightly coloured species, and also the forms able to swim. Termites build large clay nests on plains and in light forests and in tropical forest they skilfully mask the constructions on tree trunks or gnaw out cavities inside the trunk. Large mantids live mainly in tropical forest canopy and show riches of colouring and camouflage adaptations. A plenty of social insects, frequently stinging and poisonous, lives in woods. The corsair wasp belongs to such kinds; it attacks even small vertebrates and builds large nests in tree crones. There are descendants of honey bee introduced by people. Ants comprise many large army species, and also the species entering symbiosis with plants. Also there are numerous leaf-cutter ants. Lepidopterans show a variety of forms, colourings and sizes – from ordinary-looking and tiny moths up to very large morphids, swallowtails and nymphalids. Some of their species eat exclusively liquid oozing from decomposed corpses of vertebrates. On plains there are many species of blood-sucking dipterans, especially near to reservoirs. In woods of the south of the continent the variety of insects is lower, but some of them breed in great amount: midges and mosquitoes breed in cold moss bogs and small lakes.
Large scolopender centipeds live in tropical part of the continent. The large sizes and strong poison allow them to attack small bats, birds and reptiles. Some scolopenders are remarkable by very bright colouring.
Among spiders ground-dwelling bird-eating spiders and wolf spiders are characteristic. In forest canopy large orb-web spiders live, catching even small birds in giant web.
Crustaceans in fresh waters of South America are presented by numerous species of shrimps and freshwater crabs of bright colouring. At the south of the continent in rivers large isopods of, obviously, marine origin live. Numerous woodlice are found in tropical forests in ground.
Freshwater snails of tropical rivers reach great size. Some of their kinds passed to preying and eat other snails, small fishes, tadpoles and carrion. Among bivalves of southern part of the continent there are some kinds of sea origin.
|Terra del Fuego, plains and mountains|
|Pampas of Patagonia|
|Inhabitants of Amazon and Hyppolithe rivers (Amazon basin)|
|Selva of South America. (not translated, Russian version only!)|
|South America: Neocene megafauna of Grand Chaco. (not translated, Russian version only!)|
|Mirror of sky||Mountain lake in South America (Altiplano plateu) and its inhabitants from shores to depth. (not translated, Russian version only!)|
Antarctica and subantarctic islands
During the time, separating human epoch and Neocene, Antarctica
had undergone grandiose changes. First of all the geology had changed: the continent
has moved from polar position aside Meganesia, having put one of its coasts
to Indian ocean. Movement of tectonic plates had resulted in increased volcanic
activity: along the coast of the continent turned to Meganesia numerous islands,
including rather large ones, had risen from the ocean. Another center of volcanic
activity is Antarctic peninsula (a place of contact of South American and Antarctic
lithospheric plates) where some large active volcanoes exist. In other places
of continent dead volcanos exist.
Climate warming and movement of the continent to temperate latitudes had resulted in disappearing of ice cover at the significant part of Antarctica (first of all in its coastal areas). However, in polar area the huge Central Antarctic glacier continues existing, rendering essential influence to weather conditions. Also glaciers exist in mountains.
Because of thawing of ice cover Antarctica had decreased in size a little – the sea gulfs covered earlier under ice shelf have appeared, and some parts of land had been separated from the continent by sea passages. Marie Byrd land represents the large island separated by shallow sea passage from Transantarctic mountains, located on very long land area stretching from Antarctic peninsula up to Ross island. The mainland of Antarctica represents some plateau sites with separate mountain tops towering on them (for example, at Queen Maud land). Plateaus are surrounded with lowland areas in which some sea gulfs penetrate.
The coastal line of Antarctica is highly indented, and a relief as a whole is flat and smoothed by glaciers. The average height of continent above sea level is less, than in Holocene, because of thawing of ice cover. Nevertheless, in territory of Antarctica there are high mountains (up to 4 thousand meters high) and extensive mountain area of Transantarctic mountains, which separates Marie Byrd land from other areas of the continent. Because of shifting of Antarctica from polar position the South Pole in Neocene is at the bottom of Transantarctic mountains.
Though the climate of Antarctic Region in Neocene became softer, than in human epoch, all the same it is seasonal and very rigorous. The most part of continent exists in conditions of change of polar day and polar night. After short, sunny and rather warm summer (in polar day) the rigorous winter comes, accompanied with high winds and plentiful snowfalls, which cover the whole continent with thick layer of snow. In summer precipitations represent rain, but even in the middle of summer the cold returns sometimes and snow can fall for a short time. Summer temperatures reach 20 degrees above zero and more, and in winter temperature may fall to 40 degrees below zero.
In Antarctica there is a plenty of freshwater reservoirs. Numerous rivers and streams exist due to snow and rainfall, or flow down from the Central Antarctic glacier. Many of them exist temporarily, only during the time of intensive snow thawing in spring and in summer. In lowlands and on plains extensive marshes exist. Also there is a lot of small glacial and thermokarst lakes in Antarctica. In winter the majority of freshwater reservoirs freezes down to bottom.
The review is written by Simon, the forum member
The flora of Antarctica is very poor – in Neocene it was restored
in fact from zero. Because of congelation rich Antarctic flora of early Cenozoic
has disappeared in Antarctica and only its rests were kept in territory of subantarctic
islands, South America, New Zealand, Australia and Tasmania. In Neocene, when
the continent began to free of icesheet gradually, some plants of ancient Antarctic
flora had returned on continent in common with numerous new settlers.
The forest vegetation, as it exists on other continents, is absent in Antarctica. On the continent some species of nothofagus (southern beech) of South American origin grow, but their life forms are bush (including dwarf ones) and creeping shrub. Also in Antarctica some dwarf species of willow tree grow; they descend from plants introduced to New Zealand in human epoch. The Antarctic willows have small size and branch plentifully, and in spring their flowers represent the important source of nectar for local insects. Willows form special kind of “willow meadows”, entirely covered with fluffy yellow inflorescences during the blossoming period. Willows grow mainly in damp lowland areas of land whereas Nothofagus species prefer highlands.
Grassy plants of Antarctica are not numerous, but form rather large biomass. The basis of grassy vegetation is made of sedges and graminoids. From other families Asteraceae, sundews and bladderworts are common. Among sundews there are large kinds, capable to catch and digest even small birds. Bladderworts are presented not only by aquatic species with characteristic trapping leaves, but also various terrestrial forms, including rather large ones. Representatives of Geraniaceae of South African origin are a rare component of Antarctic flora. Obviously, they have got to the continent in early Neocene, when the temperate climate developed at the coast of Antarctica. Among the Antarctic plants anemochoric kinds prevail, and only some of them have lost this feature already after their ancestors appeared at this continent.
The variety of sporous plants is typical for Antarctica. Ferns are small more often, with annual fronds and perennial rhizome. There are some large species of ferns growing on Indo-Pacific coast of the continent, in the warmest areas.
The variety of bryophytes is the prominent feature of flora of Antarctica. Due to unpretentiousness and abilities to settling with the help of spores mosses of various groups became one of the first group of plants settled in places free of ice. On rocks near the edges of glaciers there are plant communities where a liverworts and mosses dominate. Peat mosses grow in wetlands, and in rivers aquatic mosses are diverse.
Antarctic lichens have great variety and form communities of fancifully looking species on naked stones, warmed up in polar summer.
The poor fauna of Antarctica of human epoch was completely
destroyed by glacier in the end of Holocene. In Neocene, when the climate became
softer, animals have occupied Antarctica again – they were descendants of sea
animals and migrants from other continents. However a variety of Antarctic fauna
is insignificant in comparison with other continents.
The mammal fauna is completely absent in Antarctica. The only exception includes algocetids – marine mammals descended from South American rodents. One of their kinds, Falkland paralgocetus, had settled in coastal waters of Antarctic Region. But these animals never go on land.
Birds are the most diverse inhabitants of Antarctic Region from among vertebrates. Absence of ground-dwelling predators and rich resources of the sea allow unnumerable colonies of sea birds to exist at the coast of Antarctica and on islands of Subantarctic. These colonies mainly include gulls, terns, skuas, gannets and tubenoses (some families, including false albatrosses). Also here cormorants of various species nest, including local flightless ones. Antarctic Region and Subantarctic represent the center of species variety of penguigull family, large flightless charadriiforms, being ecological analogues of penguins. The sea ducks eating macroalgae or invertebrates are numerous. In littoral zone sandpipers resembling plovers, tattlers, turnstones and curlews search for food. Others sandpipers are neither highly specialized (for example, representatives of oystercatcher family), nor adapted for feeding on carrion or sea waste. Besides typical sea birds, the Antarctic Region is inhabited with various kinds of divesparrows – marine passerine birds, descended of South American dippers.
Ground-dwelling birds of Antarctica are less in number, rather than sea ones. They descend from South American, New Zealand and Meganesian species. The overwhelming majority of Antarctic birds belong to migrating kinds: they spend winter in New Zealand, Meganesia, Patagonia, Tierra del Fuego and at the islands of Subantarctic. Only few species spend winter in Antarctica.
Near rivers and streams gulls and terns live and eat fish and invertebrates, including dragonflies. One species of grebes, the descendant of Tasmanian population of great crested grebe lives here. There are numerous sandpipers of various families (mainly Scopolacidae and plovers), searching for food in rivers and mossy marshes. Unusual inhabitants of Antarctica are plant-eating charadriiforms, resembling partridges in appearance and habit of life – these are descendants of South American seedsnipes.
Birds of prey of Antarctica are not numerous. In summer at the continent one species of buzzards and one caracara live. They winter in South America and migrate to Antarctica after flocks of shorebirds, when the coast of continent turns free of ice.
Riverbanks and lake shores are inhabited by ducks of various kinds eating aquatic plants and animals. Some anserine birds use another source of food – vegetative parts of ground plants. The largest herbivore of Antarctica belongs to them – it is Antarctic meadow swan.
Passerine birds are the most successful group of birds in Antarctica. Representatives of Suboscines suborder characteristic for New World live here. They belong to families of ovenbirds and tyrant flycatchers (and to family of false swallows descended from tyrant flycatchers). Tiny flightless birds of mousebird family, descended from South American tapaculos, are endemics of Antarctic Region. They lead nonmigratory way of life and replace rodents absent at the continent. From the number of songbirds Antarctic Region is inhabited by pipits, buntings, wrens and New World warblers. At some subantarctic islands birds of families of Old World warblers and Old World flycatchers (and close families), coming from Meganesia and New Zealand, live. The largest passerines of Antarctica are representatives of icterid family (grackles and New World orioles). They occupy niches of corvids and even birds of prey (for example, falcon grackle). Also in summer in Antarctica one kind of larks nests – it is a descendant of European species introduced by people to New Zealand. It winters in New Zealand.
In Antarctic Region reptiles and amphibians are absent completely, that is connected to isolation and cold climate of this continent.
Fishes of fresh waters of Antarctic Region are not numerous; they are presented exclusively by descendants of sea-dwelling species. These are fresh-water galaxias and flounders, and also representatives of separate family of vertical flatfishes, living also in waters of South America, New Zealand and Meganesia. The majority of fishes spends only warm season in rivers, and for winter migrates to river mouth or to the sea. For some species fresh waters represent a place of feeding only, and spawning takes place in sea water. However, separate species had adapted to live the year round in rivers of Antarctica, for example, freezing in ice for wintering or digging deep holes in river bottom.
Antarctic invertebrates are presented by great number of species though their variety is very insignificant in comparison with other parts of the world. Insects are most numerous among them. In conditions of extreme climate primitive insects of tiny size prosper – for example, springtails are. In Antarctic Region there is a great number of species of dragonflies of various families, and some of them grow to significant size. Their larvae occupy various ecological niches in freshwater reservoirs, and larvae of separate group of fish-dragonflies of damselfly family partly replace small freshwater fishes. Besodes for dragonflies, in fresh waters of Antarctica water bugs live – Naucoridae (creeping water bugs) and Corixidae. The number of ground-dwelling bugs is small, but they have various food predilections: there are plant-sucking kinds and predators, and also some parasitic blood-sucking bugs living in bird nests. The most numerous kinds of insects of Antarctic Region belong to dipterans: mosquitoes and midges breed in great number in fresh water. The most part of them is blood-sucking forms. Among mosquitoes of Antarctica the atypical kinds resembling horse-flies have appeared, and some ones turned to active predators similar to bugs. Larvae of crane flies replace earthworms absent at the continent and are active soil-formers. In Antarctic Region some families of beeyles live; they are mainly herbivorous, and leaf beetles among them in particular. Antarctic lepidopterans – moths and butterflies – have small size and dim colouring. From social insects at the continent there are some species of bees forming small colonies existing for one season.
Arachnids are presented by several species of spiders and mites.
In freshwater reservoirs decapods live - shrimps compete successfully to fishes. From shrimps the endemic family of Antarctic false crayfishes leading terrestrial way of life descended. The fauna of ground-dwelling crabs is poor: only at the coast and on islands of Subantarctic there are some kinds of them. In fresh waters there are also representatives of isopods.
Gastropod fauna is very poor and includes descendants of sea kinds adapted for life in fresh water. Also bivalves live in rivers.
The review is written by Simon, the forum member.
|Inhabitants of Antarctic meadows.|
|Inhabitants of Antarctic meadows.|
|Conquest of the south||The nature of Falkland Islands and shore waters of Antarctica. (not translated, Russian version only!)|
|Islands of misty sun||Chatham Archipelago, forest and seaside animals. (not translated, Russian version only!)|
Islands of Atlantic ocean
|Atlantic ocean (not translated, Russian version only!)|
The system of faults crossing Iceland.
Iceland is an island of volcanic origin and represents one
of tops of Mid-Atlantic Ridge stretching along the whole Atlantic ocean in meridional
direction. It is an island of rather ancient origin, existed in human epoch,
but expansion of Atlantic ocean is the factor promoting the maintenance of volcanic
activity. In territory of Iceland there is a plenty of dead and inactive volcanos,
and slantwise the island, from southwest to northeast, the site of youngish
rocks stretches – it is the result of expansion of Atlantic ocean. The seen
displays of volcanic activity are periodic volcanic eruptions and numerous hot
springs in valleys.
In ice age at the boundary of Holocene and Neocene Iceland was completely covered with icesheet that has resulted in smoothing of old mountains and formation of elements of the relief combined of morainic sediments. Even in Neocene in territory of the island a plenty of traces of activity of glaciers existed about 20 million years ago, at the boundary of Holocene and Neocene, is visible. The young mountain ridge was formed only after the ending of glacial epoch, and does not have signs of influence of glaciers. The central part of island is very mountainous, and closer to coast relief turns more smoothed, with separate areas of much eroded rocks. The coastal line of island is indented deeply with bays and is rocky also.
Climate of island is marine and seasonal, with increased air humidity. The climate is determined by influence of two currents: warm Gulf Stream in the west (at the coast of Greenland) and cold Antigulf Stream in the east (at the European coast). Summer at the island is cool and damp, and there are only few hot days. Winter is frosty, snowy and cold, but there are no nipping frosts because of influence of ocean.
The rivers of island are shallow, cold and short; in some valleys they can burst their banks, forming a chain of shallow boggy lakes. In mountain areas rivers are rapid and frequently form waterfalls. Mossy marshes and small lakes in river valleys also are usual.
The vegetation of Iceland has much in common with European
and American ones. During the ice age at the boundary of Holocene and Neocene
all vegetation of island was destroyed by glaciers, and after ice thawing it
began restoring from zero. The most ancient, pioneer representatives of Icelandic
flora are mosses and lichens. Spots of lichens are present on rocks, including
ones directed to the sea. Thickets of mosses are plentiful in shady and damp
Forests of Iceland in Neocene epoch are formed by tree species able to settle by means of wind. The basis of forests on dry soils is made with a pine close to American species (due to prevailing winds from west). In Alpine areas pines form creeping form. In more damp places from among conifers fur-tree grows, and also deciduous trees appear – birches, willows, elm and cold-resistant kinds of poplar. On well warmed up southern slopes maples of American origin grow. Usually maples grow as low and plentifully branching bushes, and only in the southern part of island they turn to low trees. All hardwood trees of the island cast off foliage in autumn. Bushy vegetation represents various kinds of heather frequently forming continuous thickets.
Grassy plants are presented by various kinds of sedges and graminoids with addition of forb species (of willowherb, aster and other families). In spring various bulb plants – snowdrop and onion species begin blossoming. In wetlands and at the riverbanks reedmace and reeds grow. Peat mosses are widespread and form thick peat deposits.
The fauna of Iceland of Neocene epoch is remarkable in poverty
at the level of classes and orders – many groups of animals are absent in it
or are presented by few separate species.
Mammals of Iceland are presented exclusively by several kinds of bats. Among them Icelandic leg-winged bat is remarkable – it is a carnivorous badly flying species able to run and to climb on trees well. This chiropteran replaces small carnivorous mammals absent at the island. Other mammalian orders are not present in Iceland fauna.
Birds are presented numerously in fauna of Iceland: in this respect the island resembles a little New Zealand before its colonization by people – birds occupy a significant part of ecological niches which mammals occupy at the continents.
The largest inhabitants of Iceland are gannetwhales. Rookeries of these large sea birds are located on several flat parts of coast, and separate birds or small groups of them may be met at rocky coasts.
Griffon skuas, or “sea vultures”, are predators of sea coast; these are very large skuas, analogues of smaller eagleravens from coasts of Pacific ocean. At the coast of island also warriors of Boreus, various gulls and terns nest. Gulls live also near freshwater reservoirs, but here they are less numerous.
Sandpipers are diverse and occupy sea coasts, rivers and wetlands. Some species of sandpipers live on meadows and in heather thickets, and feed on ground insects.
Large utburd owls are the top predators of the island. They have lost ability to fly, but due to large size are able to kill any inhabitant of Iceland. Also on island there are some small species of owls eating only birds, insects and chiropterans.
Xenomoa, the large gallinaceous bird descending from willow ptarmigan and lost ability to fly is the analogue of herbivorous mammals and New Zealand moas in Iceland.
Other herbivorous birds of Iceland are thick-billed geese – large migrating birds. Also in summer some small species of ducks fly to the island. Some of them migrate for wintering to Europe, and others fly to North America via Greenland.
Crails, the migrating birds wintering on islands of Macaronesia (Canary islands, New Azora) are characteristic summer inhabitants of Iceland.
Characteristic passerine birds of Iceland are representatives of Iceland wrens, clearly showing the phenomenon of adaptive radiation. Also at the island there are representatives of dippers, wagtail, swallow, finch and corvid families. The part of them lives at the island the year round, and the majority of insect-eating species flies for wintering to Europe and North America, and also to Macaronesia islands. Also at the island there are representatives of Apodiformes order – two species of swifts. One of them flies out for wintering to Africa, and another one migrates to islands of Caribbean sea.
Reptiles and amphibians are absent in fauna of Iceland.
Fauna of freshwater fishes is extremely poor – during the ice age at the boundary of Holocene and Neocene the entire freshwater ichthyofauna, including the introduced species, had become extinct beause of extensive congelation at the island. In rivers of island only gobies live, wintering and spawning in sea water. Also flounders come in rivers for feeding.
Invertebrates have settled the island in two ways: by air and from the sea. Among insects at the island dragonflies are numerous; their larvae are the main predators of shallow water reservoirs. Among other insects dipterans are diverse: flies, horse-flies, mosquitoes, crane flies and midges. Many of them feed on blood of vertebrates and massively attack large birds of island. Lepidopterans are presented by pierid and nymphalid families, various tineid and owlet moths, mainly by medium-sized species of rather dim coloring. Coleopterans of Iceland are capricorn beetles, leaf beetles and some other families. The largest insect of island is the beetle named hard-teeth giant and belonging to leaf beetle family. In territory of Iceland there are no earthworms and digging insect larvae are main soil-makers.
In fresh waters of Iceland there are many crustaceans of sea origin. In river mouths barnacles live, filtering river deposits. Scuds live not only in fresh waters, but also on land: grass flea, the jumping scud, inhabits the whole area of the island. River tree-borer, the representative of isopods, gnaws tree trunks fallen in water.
The fauna of ground-dwelling molluscs is very poor – there are only few species of small ground snails. Freshwater molluscs are absent, and only some sea species come into river mouths.
|Saga of winged warriors||Iceland and its inhabitants.(not translated, Russian version only!)|
Loki island is one of new islands in Atlantic ocean; it had
appeared above water surface only in Neocene, and its age is about 15 million
years. It is the most southern point of underwater Reykjanes Ridge in which
northern point there is an Iceland. Iceland also is the land nearest to Loki
island (the island is located to the southwest from Iceland). In its location
in relation to continents Loki island is closer to North America, rather than
Loki island is a land of volcanic origin; its area is about 400 square kilometers. It is young, and the signs of proceeding volcanic activity are visible everywhere. The island represents a volcano with several craters – the large basic crater had died out, and one of its sides had fallen off, having opened the way to ocean water. But on its external slopes there are some small active craters, erupting periodically. Coasts of Loki island are rocky, and the entrance into the central bay of island represents a narrow passage with several islets. Many islets are scattered along the coast of Loki island, and the areas surrounding active volcanoes at the edges of island represent the shallows made of black sand of volcanic origin. In internal part of Loki island there are some permanent hot springs and small thermal lakes.
The climate of Loki island is determined by presence of Gulf Stream in many respects. Due to warm ocean current it is much warmer than climate of continental Europe at the same latitude. Here summer is warm and damp, and winter is soft and snowless; winter temperatures do not fall below +10°C.
Due to clement climate Loki island is a favorable place for
development of plants. The flora of island is rather young and developed mainly
due to introduction of seeds from continents. At the first stages the settling
of plants took place due to wind, but further new species appeared on island
due to birds as the island is located at the way of birds migration between
Iceland and Macaronesia.
Tree vegetation on island represents mainly deciduous trees and bushes. Maples and elms are species of northern origin (mainly from North America), and trees of heather family occur from the south, from Macaronesia. Coniferous trees, as against the next Iceland, are rather rare – at tops of island there are small groups of pines belonging to the same species, as Icelandic ones. On external slopes of island vegetation is lower and denser, able to resist stormy weather. Here treelike plants form undersized forms with dense crone, and their trunks frequently creep and take roots.
The internal part of island protected by walls of crater is overgrown with rich broadleaf forest keeping a significant part of foliage in winter. In shady underbrush the humid microclimate is formed, promoting the development of species complex of shade-loving flora. In underbrush ferns and perennial grasses dominate. Due to humidity and low competition ferns reach almost two-meter height. Near hot springs they keep fronds the year round. Flowering plants are presented mainly by representatives of aster family, producing flying seeds with pappus. Also at the island some species of graminoids (mainly on dry slopes) and orchids (in humid internal part of island) grow.
At the island some kinds of mosses exist, forming extensive thickets in damp places. Some mosses are epiphytes. Lichens also are richly presented; some of them have the freakish shape.
At the coast in littoral zone strip there are communities of halophylic grassy plants enduring regular flooding.
It is a true island fauna initially developing without any
influence on the part of people. The significant number of kinds of animals
at the island has the American origin – obviously, the moving via Greenland
took place. Small species of invertebrates (spiders, dipterans, butterflies)
were carried from the continent by wind.
Mammals at Loki island are presented only by one species of insect-eating bats.
Fauna of birds is considerably richier. At the island small heron of American origin lives; it searches for food in coastal zone and in internal gulf of island. The original inhabitant of island is flightless sandpiper named coastal awlbill living mainly on external slopes of island. The small ground-dwelling species of sandpiper living in forest inhabits the crater. At the coast of island gulls and auks live, and from time to time warriors of Boreus appear (mainly in winter time). In coastal zone griffon skuas are found. Gannetwhales appear here seldom (only during their winter migrations), and do not form constant rookeries.
Passerine birds - the most various order of Loki island, presented by several families. The large hardly flying kind of corvids eating ground-dwelling animals lives in internal areas of island. As opposed to Iceland, at Loki island there is only one species of wrens: these birds did not give extensive radiation here like the Icelandic kinds. Finches are diverse – some insect-eating and plant-eating species of them exist here. Among migrating insect-eating birds there are swallows and swifts.
From among reptiles in fauna of island there is a large representative of lacertine lizards (Lacertidae) – fafnirella, one of few species of European origin.
Amphibians and true freshwater fishes are absent on Loki island; sea fishes come into the internal bay of island.
The climate of Loki island is warmer, than in Iceland, and fauna of invertebrates is richier here. Dragonflies are very diverse; their larvae live in streams and in small bogs. In overmoistened and marshy ground larvae of several kinds of horse-flies and common flies live. Various beetles live in forest of Loki island; these are mainly representatives of capricorn beetles, leaf beetles and scarabeid beetles. From predatory beetle families fireflies and two small species of predacious water beetles are found; one species of water beetles had adapted to life on land, and its larva also develops outside of water.
Spiders are presented exclusively by orb-web spiders related to American species. The most probable way of their settling to the island was carrying by wind of young individuals on web threads.
From crustacean species there are small ground-dwelling crabs of Grapsidae family. They live in coastal areas and around of internal bay of island, and spend on land only summer.
Ground snails of the island represent some small kinds of American origin. Probably, their ancestors had been brought on island as eggs stuck to paws of birds.
In Neocene because of volcanic activity accompanying the expansion
of Atlantic ocean, the part of Azores (Pico, Terceira, Faial, Sao Jorge and
Graciosa) has turned to unite New Azora island. The formation of the island
proceeded in some stages and was accompanied by increase of volcanic activity.
The last stage of formation of island was finished approximately 15 million
years after extinction of mankind.
New Azora of Neocene epoch is a mountainous island combined of rocks of volcanic origin. On edges of island there are areas of older and more eroded rocks with deposits of volcanic ash in lowlands, marking the regular periods of volcanic activity. The central part of island is high, young and rather active volcano. On slopes of this volcano there are some hot springs, and some areas of slopes represent lava fields with separate sites of pioneer vegetation.
New Azora island is located in tropical latitudes, and seasonal changes of climate are poorly expressed – only in winter the amount of precipitation is less. Climatic conditions at New Azora are substantially determined by Gulf Stream and Antigulf Stream. Due to Antigulf Stream at the island fogs are very often, especially in winter time. In summer due to Gulf Stream there is a high humidity of air at the island.
Mountains of island serve as places of condensation of moisture, and on slopes streams flow down, merging to small rivers. In mountain valleys there are lakes and marshes.
New Azora as a unite structure is rather young island, but
Azores as its predecessors existed in human epoch. Because of it in island flora
of Neocene the influence of human activity is visible – among island plants
there are kinds impossible to appear on New Azora in natural way.
In mountains, where the climate is little bit cooler, cypresses, descendants of the species introduced by people, and junipers, related to forms from Canary islands grow. They form dense forests at tops, preferring humid air. Below them there is the zone of heat- and moistureloving forests showing some features characteristic for tropical forest. They are formed of large treelike heathers and some other trees of tropical origin – descendants of the species settled from Africa. For these forests lianes (various kinds of ivy and Clemathis), and also epiphytes – orchids, mosses and ferns – are characteristic.
Grassy plants show mainly their European origin – their settling had taken place due to Antigulf Stream. To a lesser degree in island flora the African kinds are presented (their ancestors have got to the island due to birds or wind). Graminoids and sedges have rather low variety, but form extended thickets, enduring the competition to other plants due to resistance to trampling and grazing. In island flora orchids, including epiphytic ones, are richly presented. Among plants of aster family there are large grasses with prickly leaves, and also low bushes with woody stalks.
In mountain areas where the number of plant-eating animals is less, large grassy plants develop. One of them is a huge kind of plantain, so-called “New Azora banana”.
Closer to sea coast, in drier areas of foothills the zone of evergreen forests of Mediterranean type is developed; it is formed of descendants of some cultural trees – laurel tree, olive tree, myrtle and lemon tree. Here hygrophilous ferns and mosses grow only in shady gorges and river valleys. In dry forests there are sporadic thickets of date palm, the descendant of the species cultivated in human epoch. The date palm is able to form almost uniform thickets stretching for hundreds meters due to ability to form root shoots. One more sign of former human activity is the local treelike kind of prickly pear cactus, widespread at the significant part of coastal lowlands of island.
The coastal areas of island having characteristic arid conditions are occupied by communities of drought-resistant plants. A typical plant community at the coast of New Azora is scrub (small-leaved drought-resistant, frequently prickly bushes). Also the small number of succulent plants lives here; these are spurges (settled to the island in natural way), agaves and aloe (descendants of the species introduced by people). Large agaves form numerous groups above which tree-sized flower stalks tower.
In littoral zone there is a complex of salt-resistant species of flowering plants. Here leafless sea aster forms extensive thickets, but it blossoms rather seldom, expanding mainly in vegetative way.
To the south from New Azora extensive algal fields stretch. Here the branch of sea current forms local slow whirlpool in which floating brown macroalgae grow, forming rather dense cover on the sea surface.
In fauna of New Azora the human influence has an effect even
millions years after human extiction. In first millions years on Azores the
feral goats lived and formed a complex of dwarf kinds, but at various stages
of formation of New Azora they had died out as a result of volcanic eruptions.
In Neocene fauna of New Azora is formed exclusively of descendants of small
species kept from human epoch, and of descendants of later settlers of the island.
Mammals in fauna of New Azora represent the result of human activity. At the island some kinds of hedgehogs (descendants of the European hedgehog) live, and among them one kind is able to climb up trees. Some kinds of bats of various families are independent immigrants to the island. Because of presence of ground-dwelling predators no one of their species express the propensities to loss of flying ability.
The largest herbivore of New Azora is tardolagus – large descendant of introduced European rabbit. Also at the island some smaller species of rabbits exist, inhabiting scrub and forests of various types.
The main predator of island is martilla – the large descendant of introduced ferret.
Rodents are descendants of mice and rats introduced to islands in human epoch. Some kinds of these rodents inhabit in fact all island biotopes.
The fauna of birds of New Azora is very rich. Despite of presence of predators from among mammals, on New Azora some kinds of flightless birds exist. Plesioloon of Gaviiformes order, large sea bird adapted to long migrations in ocean lives on island. One more species of flightless loons is laughterloon similar to small a seal and living also on Canary islands and the Atlantic coast of Europe. Loons in tropical latitudes are settlers from the north, the mark of extensive congelation at the boundary of Holocene and Neocene.
One more kind of flightless birds is Azorean false dodo, the flightless descendant of fulmar. The early stages of its evolution connected to loss of ability to flight passed at one of islands became further a part of New Azora. This species proved to be competitive enough in neighbourhood of mammalian predators.
On beaches of New Azora tropical gannetwhales gather in rookeries; they are relatives of northern species appearing in these places extremely seldom.
Among shorebirds birds on island there are small herons searching for food in wood litter and preferring to nest near lakes and bogs in mountain valleys. Also near bogs of island Macaronesian crail winters and two kinds of true rails live the year round. Small rails partly lost ability to flight live on small islands near New Azora where mammals are absent. The chardriiform order is presented at New Azora island by griffon skuas, various species of gulls and sandpipers. Ghostly wanderer, bird searching for food on algal fields in the sea is original endemic species.
Also the inhabitant of algal fields is sargasso eider – the species came from the north. In marshes of the island some species of migrating ducks (nesting in Europe and Iceland) and one settled species live.
From among falcon birds at the island sea harrier lives – it is a bird of prey adapted to hunt prey on algal fields. Another kind of predatory birds, small hawk species, is found in forests of island. Also island is a homeland for two species of barn owls – large one specializing on feeding on vertebrate animals, and small one hunting mainly insects.
Gallinaceous birds are presented in island fauna by members of pheasant family. Some kinds of Azorean partridges are descendants of quail introduced in human epoch.
Some groups of land birds are absent at New Azora, for example, nightjars, woodpeckers and coraciiforms. Swifts are presented by sole species of endemic genus Azorapus.
Passerine bird order comprise many small species of several families. Among wagtails some species of endemic genera had evolved – soilprobers and stream wagtail having convergent similarity to dippers. Some kinds of finches evolved from ancestors of the European origin live in forests of the island. Titmouses are presented by several insect-eating kinds, one of which has deep specialization for search of insects under tree bark. From among corvid birds Azorean magpies and small omnivorous kind of crows live at the island.
Reptiles of New Azora are not numerous and include one large representative of lacertid lizards (Lacertidae) and some species of small geckos related to each other.
Amphibians and freshwater fishes are absent at New Azora.
The fauna of invertebrates shows wide spectrum of species evolved in due course of long-term evolution from few ancestral forms.
The majority of insects descends from well flying ancestors which have independently reached up to island. Dragonflies are typical for freshwater reservoirs where their larvae replace small freshwater fishes. Odonata order is presented both by damselflies having mostly pelagic larvae, and dragonflies having bottom-dwelling larvae.
Endemic kinds of bugs are original. New Azora spike-creeper bug is a symbiote and cleaner of local kinds of hedgehogs. Most likely, it appeared on island due to migrating birds, because it is related to African kinds of these insects. Among herbivorous bugs giant lace bug is remarkable, imitating tree leaf. At the island some small species of stinkbugs and assassin bugs live.
Among butterflies there are some species of pierids and nymphalids of European origin. Some species of nymphalids reach large size comparable to size of tropical butterflies.
Beetles include representatives of leaf beetles, scarabeids and small rove beetles of European origin. Some representatives of fireflies belong to kinds of American origin.
The fauna of dipterans is diverse and includes some kinds of flies, mosquitoes and midges. The unique species of midges lives at the algal fields near to island, developing in sea water and never appearing in fresh water or on land.
Ground-dwelling crabs of Grapsidae family are characteristic inhabitants of island. Some kinds of these crustaceans occupy various ecological niches of island, playing a large role in soil-making.
Ground-dwelling snails are presented by several kinds of one genus of pulmonate snails and are descendants of edible snail Helix pomatia got on islands in human epoch and survived successfully after volcanic eruptions accompanied the formation of New Azora.
|New Azora island, shorebirds and other animals of seashore.|
Great Antigua island is formed at the edge of Caribbean sea
as a result of merge of Haiti, Puerto Rico and several smaller islands of Antilles
archipelago located to the east from them. It grows out the tectonic processes
taking place in Central America and is directly connected to expansion of Atlantic
ocean. Great Antigua is located at the edge of Caribbean lithospheric plate
and represents very extended narrow island on which there are some dead and
active volcanoes of different age expressing the history of formation and changing
of island. During the becoming Great Antigua was a part of Antillean land bridge
via which an exchange of flora and fauna between North and South America took
place for any time.
The significant part of the area of Great Antigua is made of mountains of various ages, and only coastal areas represent a narrow plain zone.
Climate of island is tropical only, warm and humid the year round. In many respects it is determined by seas surrounding this island, therefore seasonal climate changes are expressed very implicitly – only in winter precipitation is more a little bit. In mountain areas it is cooler and drier, rather than at the coast, but here the temperature also falls below +20°С only in rare case. Rains fall almost every day, and only their duration varies. Since spring up to an autumn tropical hurricanes are frequent.
Rivers of island are deep and not drying up, but rather short. Rains represent a source of water for them. In mountain valleys there are many small lakes and bogs; marshy sites may be found in lower reaches of rivers.
Tropical forests covering in total about three quarters of
the area of island represent the basic type of vegetation of Great Antigua.
In mountains tropical forests are replaced by another type of vegetation – light
forests with elements of tropical savanna. Pines introduced in historical epoch
form light forests on dry and well-drained soils, and drought-resistant scrub
and cactuses live in underbrush of pine forests. On dry hillsides cactuses form
continuous thickets in common with agaves of various species.
Tropical forests are remarkable in high degree of species variety of trees. Large lianes and various epiphytes – ferns, bromeliads and orchids, and also Gesneriaceae and cacti of Hylocereinae tribe – are very characteristic. On the broken areas of forests, in river valleys, large rhizomatic grasses expand, including hybridogenous species of bananas descended from feral cultivated forms. One of original plants of tropical forests of Great Antigua is pipe-flowered tobacco tree; its tube-like flowers are strictly adapted to pollination by one species of moth.
On plains in coastal areas in forest a plenty of palms grows. Some of them grow alone, towering above forest canopy, and others form extended monospecific thickets.
At coasts palms are prevailing group of wood plants. Extensive mangrove forests grow in shallow coastal waters.
Tropical conditions are favorable for keeping of the variety
of island fauna. In human epoch the animals of various groups not found here
earlier had been introduced to the islands of Caribbean sea, and their descendants
represent a part of Neocene faunae of Great Antigua. As a whole the fauna of
island belongs to Neotropical zoogeographic realm, but in its structure the
great influence of Holarctic is appreciable.
In early Neocene islands of Caribbean sea represented faltering, but working “land bridge” for settling of South American fauna to the north. Because of non-simultaneous emerging and submerging of islands only the part of North American species had settled via Antillean bridge to South America, but much more South American forms had penetrated to the north.
In spite of the fact that Great Antigua is an island, the fauna of mammals has many features characteristic for continents. In particular, here animals of typically overland groups are present.
Marsupial mammals of Great Antigua are only opossums of North American origin, arboreal omnivores of various sizes. One kind of opossum resembles continental North American geopossums – it is not the best tree-climber and prefers to search for food on the ground.
The variety of insectivores is poor and includes some species of shrews of North American origin; endemic solenodons had died out at the end of historical epoch.
Chiropterans of Great Antigua are very diverse and include species of several families. Among them there are numerous insect-eating species, some frugivorous ones, predators and one dwarf species feeding on blood of vertebrates.
In Antiguan fauna there are representatives of primate order. Old World monkeys (green monkeys from Africa) introduced in historical epoch have successfully survived in time of ecological crisis, evolved to new species and even migrated to North America. Also on island there are some kinds of small broad-nosed monkeys of South American origin – marmosets inhabiting bushes and forest canopy. One species of marmosets lives in mangrove forests.
From among carnivores dwarf kinds of canids – uktenas, descendants of coyotes, live on this island. There are some small forest-dwelling species of cats, American raccoon lemuroids and true raccoons. The result of human activity is the presence on Great Antigua of viverrids – descendants of mongooses introduced in historical time.
The rodent order includes numerous representatives of both Holarctic and Neotropical groups. From among Holarctic rodents squirrels and flying squirrels are usual. Also there are various kinds of mice and rats – mainly descendants of the species introduced by people. Endemic hutia family had died out at the end of human epoch. Scaly porcupines leading ground and arboreal way of life are settlers from South America. Representatives of agouti family were kept from human epoch and evolved further. One of the most unusual groups of rodents is the deermara family of South American origin. Its representative in Great Antigua is mazamara, the dwarf kind, not exceeding a dog in size.
The fauna of birds of Great Antigua is rich, as it is characteristic for tropical areas. Some groups of birds characteristic for North and South America are absent here, but the species diversity is very rich in general.
Humid climate and abundance of freshwater reservoirs promote a variety of shorebirds. Near marshes and rivers ibises and storks, and also numerous herons live. Among herons there are forms living in mangrove thickets at the sea coast. Among sea birds various kinds of gulls and tropical terns are usual. The majority of species of sandpipers represents the birds migrating for wintering from North or South America. At Great Antigua crails from North America winter. Rails are found everywhere at the riverbanks and in bush thickets, avoiding highland areas.
Ducks are widespread everywhere, expressing a variety of sizes and coloration patterns. Among them there is a species adapted to brood parasitism.
Gallinaceous birds of Great Antigua are descendants of domestic chicken and New World quails. The significant part of these kinds lives in forests of the island, but some species live in mountain light forests.
Predatory birds of Great Antigua are very diverse. Large flesh-eating birds are New World vultures, preferring light forests and coastal areas. Kites and caracaras of South American origin live in forest areas. Owls are represented by various kinds of barn owls and true owls.
In tropical sorests of island parakeets are numerous – mainly small species, but there are also some large ones eating nuts with hard shell.
Various woodpeckers live at the Great Antigua. Among them there are species leading an unusual way of life: inhabitants of mangrove thickets and ones searching for food on reeves during the outflow. Large flightless woodpecker from Great Antigua is the representative of separate family of Antiguan woodpeckers.
Trogons are characteristic group of forest birds of Great Antigua. Cuckooes are represented by a plenty of species; largest ones of them eat small vertebrates, and small ones are strict insect-eaters and can eat even bees having poisonous sting.
The most diverse order of birds is passerine bird order. Among them there are various suboscines of South American origin – cotingas and tyrant flycatchers. Songbirds have much gerater variety of families: Parulidae, thrushes, weaverbirds (descendants of introduced house sparrow), finches, starlings (descendants of European starling introduced to North America) and corvids.
A variety of reptiles is very great due to tropical climate. Among turtle order there are representatives of tortoise family (Testudinidae), and also species of family Emydidae – box turtles and some kinds of freshwater turtles. Among squamates very large iguanid terraguana is remarkable – it is the largest predator of island. In addition to it island is inhabited by many species of small iguanas and also teiids (whiptails). Geckos are found in tropical forests; among them there are some dwarf species. Among snakes small boas, and also rattlesnakes and blind snakes are most typical.
Amphibians are represented only by Anura order. At the Great Antigua there are representatives of tree frogs and saddleback toad families settled to islands of Caribbean sea in natural way. Besides them in fauna of island there are representatives of toad family – descendants of cane toad introduced by people. The most part of frogs lives in tropical forest canopy.
The fauna of fishes of Great Antigua is rather poor in comparison with continental one. Here there are no representatives of many groups of the fishes existing on the nearby continents.
Siluriform fishes are presented by several kinds of sea-dwelling ariid catfishes (Ariidae) coming into rivers. Also here clariid catfishes live; they are descendants of the species introduced by people to Florida and settled therefrom to south via Cuba. Cyprinid fishes had been introduced in historical epoch, but had gradually died out because of a competition to other groups of fishes. Among percoid fishes there are some kinds of croakers of sea origin, and also of cichlids: local species of cichlasomas and descendants of introduced Mozambique tilapia. Viviparous fishes making the most part of freshwater ichthyofauna reach the especial variety at Great Antigua. Representatives of various families of live-bearers of Caribbean sea come into the rivers; due to ability to give rise to live fry they can pass the whole life cycle in fresh water. Also in lower reaches of rivers pipefishes, some kinds of pufferfishes and original viviparous vertical live-bearers are found. Sharks and rays frequently come into the rivers of island. In cave systems of Great Antigua some local species of fishes live – viviparous fishes and dwarf cichlids.
Invertebrates of Great Antigua are very diverse; among them there are many highly specialized forms. For tropical forests various cockroaches, including small flying and large digging forms, are characteristic. Among bugs there are many large plant-eating species of freakish shape and colouring; there are predatory species, including some aquatic bugs of various families. Lepidopterans express great species variety. Some of them are remarkable due to large size: Antiguan giant hawk moth has proboscis of half-meter length. Local swallowtail butterflies differ in very large size and bright colouring. Social hymenopters of the island are descendants both of South American species, and of introduced honey bees. Solitary wasps of the island show various adaptations to parasitism – independently from ichneumons of Southeast Asia they have adapted to parasitism on small vertebrates. On the island many species of ants live. Beetles are very diverse, among them there are numerous predatory (ground beetles, soldier beetles, lightbugs, etc.) and plant-eating forms. Among dipterans mosquitoes and flies reach great variety; among flies there are very large kinds.
For damp places large millipeds and centipeds (scolopenders) are characteristic. Some predatory centipeds eat small birds and bats, killing them by one sting.
The fauna of arachnids includes large scorpions, various spiders (including large bird-eating spiders) and mites.
Among crustaceans ground-dwelling crabs of family Grapsidae are very characteristic. Some crabs had developed life in fresh water, but for breeding they migrate to the sea. The mark of former connection of islands of Caribbean sea with North America is the presence of crayfishes of American family Cambaridae at Great Antigua (and also at nearby Cuba); among them there are some small and brightly coloured species. Also on the island freshwater shrimps live.
Due to regular connections with continent on island various pulmonate gastropods live. Species from tropical forests have variously coloured shells and form many local subspecies and color forms in isolated valleys and volcanic craters. Various kinds of ramshorn snails, and also large apple snails inhabit rivers.
|Fishes and other inhabitants of Cariffean Sea. (not translated, Russian version only!)|
|Great Antigua island, tropical forest and mountains. (not translated, Russian version only!)|
During the expansion of Atlantic Saint Peter and Saint Paul
archipelago located in tropical latitudes of Atlantic had sunk, but further
instead of it in early Neocene from ocean depths islands rose repeatedly. The
last of them is New Tortuga island which exists for approximately ten millions
years. This island of volcanic origin represents some volcanic cones, oldest
of which are partly destroyed. Near New Tortuga there are some small islands,
also of volcanic origin. The area of New Tortuga is about 1000 square kilometers.
Signs of volcanic activity are visible at the island –there are some places where hot springs are. Sometimes in various places of island there are emissions of volcanic gases, suffocating all live creatures around.
The relief of island is not uniform, but the most part of territory represents mountainous area. Flatland sites represent mainly a narrow strip of the coast made of volcanic sand.
New Tortuga is located in zone of equatorial climate. Here the hot climate dominates the year round, and the amount of precipitation varies a little bit in various months. Due to rains at the island there is a plenty of reservoirs – short rivers and small lakes. Long-term lakes exist in craters of dead volcanos.
There are tropical forests on New Tortuga similar to South
American ones but formed mainly by trees which seeds are carried by wind. Seeds
of some trees had lost this ability, but keep rudimentary wing or pappus indicating
the way of occurrence of ancestors of these plants at the island. Some of plants
had been brought from the continent by birds.
A species variety of trees on island is rather poor; they are mainly representatives of treelike spurges and plants of aster family. A number of groups of plants characteristic for South America (families Lecythidaceae, Sterculiaceae, Fabaceae, etc.) is not present at the island. Palms growing on New Tortuga are descendants of kinds which seeds had been brought by water. At the coast there are mangrove forests formed by one species of mangrove trees.
Grassy plants are presented very richly, and among them many endemics exist. Bromeliads of American origin are very numerous, and among them there are epiphytes and some large ground species growing mainly in mountains. All bromeliads have pools for water in middle of the rosette or in leaf axils, always full of water due to rains.
In tropical forest numerous epiphytes (orchids, begonias and others) and lianes grow. On island various ground and epiphytic ferns are found. The majority of them has American origin, and there is one species of African origin.
As New Tortuga was formed after human disappearance, the fauna
of this island was formed by pure natural way and it lacks many groups of ground-dwelling
animals. The fauna of New Tortuga was formed mainly due to Neotropical fauna.
Taken out by the rivers on plant “rafts” animals should do a long way, having
got in the ring of Brazil current flowing to the south along the coast of South
America and to return to the north in South Equatorial current.
Mammals of New Tortuga are unnumerous – there are only few species of small bats. Among them there are some insectivorous species and one nectar-eating one.
Birds inhabiting the island are much more diverse. At the coast of island numerous sea birds live – gulls and sandpipers. Among gulls there is one original kind - the ground gull which is ground-dwelling bird replacing corvids absent at the island. From among gruiform birds on New Тортуге chicken rail lives; it is the omnivorous ground-dwelling bird lost ability to fly. Number of predatory birds of New Tortuga is small: there is endemic New Tortugan barn owl and in light forests small kind of hawk lives. Island is inhabited by various small passerine birds, both Suboscines and songbirds. Among them there are species of both American and African origin. Among the American kinds there are ovenbirds and cotingas (each family is presented by 1 species), and African birds are presented by several finches.
Due to tropical climate reptiles prosper on island. The island has received the name due to the variety of turtles which have created unique fauna. Turtles of Podocnemididae family originating from South America became dominant ground-dwelling animals. Due to absence of competition among them predatory, grazing and sea-dwelling forms, and even one arboreal tree-climbing species had evolved. Lizards of island are presented by several species of geckos of African origin, and also by small teiids descending from South America.
Amphibians and fresh-water fishes are absent on island.
The invertebrate fauna shows great variety and high degree of endemism. Insects are presented by various beetles; the part of which descends from Africa (flower chafers and jewel beetles). Among beetles of American origin fireflies and soldier beetles are present. Due to prevalence of east winds the fauna of butterflies was formed almost exclusively by species of African origin. On island some kinds of nymphalids and swallowtails, and also numerous small moths live. Butterflies of American origin represent some species of Heliconiinae family (longwings). Also at the island some kinds of dipterans live, including blood-sucking turtle fly.
Spiders of New Tortuga are of American origin. On island some related species of jumping spiders live, obviously descended from the common ancestor.
For island fauna ground-dwelling crabs playing a role of scavengers and small predators are characteristic. They compete to spiders and replace ground spiders like tarantulas.
From among molluscs on island there are some species of snails of American origin related to each other and differing in ecology.
|Stone backs||Island in tropical zone of Atlantic ocean; its inhabitants - birds and reptiles. (not translated, Russian version only!)|
Falkland islands are located approximately in 700 kilometers
from the Atlantic coast of South America. They are located on the same continental
plate, far from areas of volcanic activity; therefore the geology of islands
almost has not changed from human epoch. Only during the ice age at the boundary
of Holocene and Neocene on the significant part of islands the iceshield had
appeared, and it smoothed in great degree a lay of land and had left swells
of moraine sediments.
Coasts of islands are rocky and are indented with bays deeply penetrating into land. Around of two main islands many shallows and islets are scattered.
The climate of Falkland islands almost completely depends on ocean. Islands are washed by cold current, and waters from equator reach islands being cooled down in great degree. Besides islands have moved to the south in common with South America relatively to their position in Holocene epoch. Because of it the climate of islands is still cold, despite of the general warming in Neocene. Winter temperatures frequently fall below zero and on islands snow falls. Summer is cool, hot weather is kept for some weeks in the middle of summer. The significant part of year on islands fogs are usual, and there are frosts at night and in the morning.
On Falkland islands there are only few constant freshwater reservoirs. Mainly these are lakes existing due to snow and rain water. The rivers on islands are short, narrow and shallow, with cold water.
Vegetation of Falkland islands is very poor. It takes place
due to rigorous climate, and also to activity of grazing mammals. Thickets of
high grass (so called “tussac grass”) characteristic for human epoch have disappeared
in Neocene on the main islands, having kept as relicts only on fat islets. Feral
domestic animals at the end of human epoch had exterminated a significant number
of species of endemic plants and had destroyed natural plant communities. In
Neocene the grass cover on large islands represents dense sod of rather low
graminoids with a part of forbs. Grassy plants from dicots (parsley, aster families
and so forth) grow mainly among stones, in places less accessible for herbivorous
mammals. Bush vegetation is very poor – there are only two species of heather.
Trees are absent on islands.
In marshes various species of sedges and other grassy plants grow. At the islands there are peat bogs and turbaries.
Among sporous plants ferns are very characteristic. Mosses are presented by a plenty of species and grow mainly among rocks.
In shallow water near the coast brown macroalgae expand, forming extended thickets (kelp).
The fauna of Falkland islands of Neocene epoch was formed by
several ways. Some of inhabitants of islands have got there by air or from the
sea in the natural way; also there are many descendants of species of ground-dwelling
animals introduced in human epoch. At the boundary of Holocene and Neocene the
congelation had covered islands with glaciers almost completely, having left
some “oases” along iceshield edge where some ground-dwelling animals had kept.
After the receding of the glacier animals had settled islands everywhere.
From mammal classus on Falkland islands carnivores live – the descendants of South American grey fox introduced in human epoch. Cats also introduced by people had died out because of congelation, not having sustained a competition to canids and disappearance of suitable habitats. The main herbivores are large descendants of introduced rabbits. Also on islands small descendants of rats introduced by people live. In coastal waters Falkland paralgocetus lives – it is the largest local mammalian species and one of the largest mammals of Neocene. This giant eats brown algae and does not leave the sea. One more sea mammal of islands is piscivorous ayapuh similar in way of life to otter.
The fauna of birds is much more diverse. Many birds are migrating, and the significant part of birds depends on sea in the life. In rivers and lakes one small species of grebes being found also in the south of Patagonia and on Tierra del Fuego lives. Also near freshwater reservoirs various ducks and sandpipers nest. The fauna of sea birds is much more diverse. The endemic species is Falkland kaveskar – the representative of penguigulls. Besides it at the islands Patagonian kaveskar and proper penguigulls of several kinds are found; gulls and terns also are diverse. Many species of sandpipers specialized to feeding on various kinds of sea invertebrates live in coastal zone. Occasionally on islands nomade albatross nests, but this species prefers to settle on small islets and does not form large rookeries. Ground birds are presented only by several species of tyrant flycatchers, migrating kinds of grackles, pipits and one species of South American dippers, and also by settled representatives of buntings. The main predatory birds of islands are large settled caracara and the small species of owl.
Reptiles and amphibians are not present on Falkland islands.
Freshwater fishes on islands are presented exclusively by descendant of the trout introduced in human epoch. This species, dwarf Falkland smalt, shows a significant variety of local forms in diet, colouring and a way of life – from small insect-eating varieties up to medium-sized cannibalistic predators.
The fauna of invertebrates of Falkland islands is poor. From insects on islands there are some species of endemic beetles lost ability to fly, and also some species of tineid moths and a kind of nymphalids almost completely lost ability to fly. In fresh waters of islands some kinds of isopods live. Some kinds of digging isopods live in ground in coastal areas. At the coast ground-dwelling kinds of scuds having convergent similarity to Icelandic ones live.
Some kinds of bivalves and cirripeds (crustaceans) live in lower reaches of the rivers.
|The winning of the south||The nature of Falkland Islands and shore waters of Antarctica. (not translated, Russian version only!)|
|Pelagic animals of Pacific ocean.|
|Plankton animals of Pacific ocean.|
|Pacific ocean, depth of 2500 meters. (not translated, Russian version only!)|
|Bottom of Pacific ocean. (not translated, Russian version only!)|
|Pacific ocean. Giant species of sea turtles, its parasites and symbiotes. (not translated, Russian version only!)|
|Underwater fortress||Inhabitants of reeves of tropical zone of Pacific ocean - fishes and invertebrates. (not translated, Russian version only!)|
The location of Hawaiian islands marks the place of the magma
stream flowing out from Earth mantle and burning thin oceanic crust. As a result
of movements of lithospheric plates the stream of magma had burnt a chain of
islands in oceanic crust. The archipelago is composed of mountainous islands
precisely differing from each other by age and relief.
The most western of large islands is Kauai, one of the oldest ones in archipelago, having the lowest volcanic activity. This island has very smoothed relief and very eroded rocks, and tectonic activity is limited to earthquakes. Younger islands placed to the southeast from Kauai are active volcanos where liquid lava flows are frequent (volcanic activity amplifies in direction from northwest to southeast). In Neocene Hekeua, the youngest island having the greatest volcanic activity had elongated the island chain. In general the archipelago had shifted a little to northwest during the time passed from human epoch.
In island sediments the evidence of great eruption accompanied the formation of Hekeua island may be found.
In addition to large islands, a number of small islets near the coasts exists in archipelago, facilitating the settling of representatives of flora and fauna.
The archipelago is located in the zone of tropical marine climate, determined by Pacific Ocean in many respects. Seasonal changes of climate are not expressed; the climate is humid and warm the year round. Due to their height above ocean level tops of mountains serve as the natural condensers of moisture providing rainfall almost every day.
Alpine areas are the zone of temperate climate, and at the highest tops snow lays, despite of tropical location of islands.
Due to plenty of precipitations at Hawaiian islands many freshwater reservoirs exist. The rivers of Hawaiian islands are short, shallow and full of rapids; in gorges and mountain valleys lakes and bogs are formed.
People had caused great harm to native flora which developed
during millions years before the epoch of historical colonization of islands.
In Neocene flora of islands there are many descendants of introduced plants,
but descendants of the species existed before historical colonization are almost
absent. However, there are the species appeared at the islands in natural way
already after human disappearance. The reasons of diversity of Neocene Hawaiian
flora are altitudinal zonation, presence of plenty of rather isolated habitats
and isolation of islands from each other by sea passages.
In lowland parts of Hawaiian islands warm and humid climate dominates. In valleys and foothills extensive forests of water- and heat-loving plants grow. Among pioneer plants in sites of broken forest stand the community of fast-growing woody plants develops, among which there are descendants of papaya and Ravenala introduced in historical epoch. In humid forests acacias of local kinds (among which there are some ornithophilic species), ficuses and fan-leaved palms dominate. Treelike representatives of Asteraceae, endemics of these islands, are characteristic for these woods. The variety of tree vegetation had caused the appearing of an interesting kind of parasitic trees – non-green sandal tree. This tree had completely lost chlorophyll and receives nutrition exclusively due to surrounding trees. In forest canopy a plenty of epiphytic plants exists – orchids (of several endemic genera), ferns and begonias. Among epiphytes there are also sundews, the insectivorous plants. In damaged areas of forest and in forest canopy a plenty of lianes grows.
On slopes of mountains forests grow lower, and expressed levels of forest disappear. The plenty of the plants able to take roots from trunk and branches appears here, forming continuous and almost impassable thickets on the slope. Descendants of plants introduced in human epoch –Myrica, guava and Poinsettia (flaming poisonous tree is one of them) – dominate here.
In shady gorges the complex of shade-loving forests is developed of tree ferns (also the descendants of introduced species) with separate tall representatives of flowering plants. In these forests there is a humid microclimate and thickets of mosses of various species and small grassy ferns are formed. From among flowering plants in fern woods orchids and begonias live.
Farther from ocean coast, in the areas protected by mountain ridges from ocean winds, more xerophilous forests of descendants of olive, palms and Yucca (it is a relict dyed out on the continent, but survived at the archipelago) grow. On wet and poor soil at the abundance of sunlight bamboo forests develop – usually they represent one stage of restoration of vegetation after volcanic eruptions or occupy areas of damaged forest.
On large and rather young islands there is a complex of Alpine forest vegetation living in conditions of relative dryness and superfluous solar illumination. The original kind of Hawaiian vegetation is “silver forests” formed by photophilous plants with silvery down and wax cover on leaves – gum trees, Grevillea (silver oak), palms and acacias. These forests are rarefied and have rich underbrush. Higher on mountain slopes deciduous woods are replaced by coniferous ones formed of Araucaria, pine and juniper. In high mountains creeping araucarias grow, and also rhododendrons descended from Asian species introduced in historical epoch. At tops of mountains, along the border of snow cover, the complex of vegetation adapted to rigorous conditions of high mountains is developed. Few large species of grasses and numerous undersized and cushion-like plants having convergent similarity to tundra vegetation live here. In mountain areas there were relicts of ice age, representatives of flora of temperate climatic zone: cottongrass and sundew. Also highly specialized grassy plants originated from warmer climatic zone, adapted back to cold and abundance of sunlight live in mountains.
Lava fields are characteristic habitats of islands having high level of volcanic activity. Here the complex of pioneer vegetation able to exist on soils poor in organic substances is developed. A characteristic species of such plants is “silver foam”, the undersized kind of Asteraceae. As the accumulation of organic substances proceeds, at the areas burned by lava Myrica and bamboo settle, being replaced later by true forest plants.
In wetlands thickets of large species of Cyperus develop, resembling vaguely African papyrus. On marshland soil huge descendants of taro (Colocasia) grow, and shallow parts of fast flowing rivers are occupied by local varieties of water lilies and by other descendants of aquatic plants introduced by people.
At sea coasts, in conditions of abundance of sunlight and salinity of ground, the special type of plant communities is formed. Coastal shoalinesses are covered with thickets of sea coconut palm – the palm of special kind forming the analogue of mangrove forests. The second line of vegetation is made of thickets of screw palm (Pandanus) and giant fennel tree grass (of Asian origin). Farther from sea coastal plant communities are gradually replaced by tropical forests.
The originality of Hawaiian fauna naturally developed in prehistoric
epoch had been lost in great degree after human colonization of islands. Human
activity had substantially changed the character of island fauna at the classus
In Neocene fauna of Hawaii there are numerous kinds of mammals – it is the result of human activity in many respects. Before people exclusively chiropterans lived on islands, but in Neocene on islands a plenty of ground-dwelling mammals is found. Rather atypical representative of mammals is monkey wallaby, the tree-climbing marsupial mammal. Also some kinds of wallabies live in mountain forests and lead more typical terrestrial way of life. All of them are descendants of brush-tailed rock-wallaby Petrogale penicillata introduced from Australia and naturalized successfully. Placental mammals are presented at Hawaii by carnivores, artiodactyls, rodents and chiropterans. Among carnivoran mammals ilioholokai is interesting – it is large seal-looking descendant of mongooses living at sea coast. Other descendants of mongooses lead ground and arboreal lifestyle, turned to ecological analogues of ermines, martens and foxes. Artiodactyls of Hawaiian islands represent some species of deer descended from Asian axis deer introduced in human epoch. The most numerous group of Hawaiian mammals is the rodents order including descendants of rats and mice introduced to islands. The largest one among them is kapo, which is a key distributor of seeds of many kinds of local trees. Adaptive radiation had caused the appearing on islands of numerous rats differing from each other in habit of life, diet and behaviour. Among them omnivorous bamboo rats and tree-climbing plant-eating flower rats are characteristic. Pacific false mole rats, digging rodents lacking eyes make the separate endemic family. Only chiropterans among which there are predators and insectivorous forms had independently settled to islands.
Despite of presence of mammals at Hawaii, birds are very diverse on islands. On small islets near coasts of main islands of archipelago sea birds nest – gulls and sandpipers. Various tubenoses live at coasts of islands, but they prefer to nest on islets far from coast, where there are no mammals. Among pelecaniform birds there are some small species of gannets. Also on islands non-migrating auks live; they obviously settled to the south in ice age and formed an endemic genus living exclusively at Hawaii. Among other shorebirds herons of several kinds, not migrating, but not lost ability to fly are characteristic for islands. Also there is a large species of heron of endemic genus searching for food mainly on the ground. Heliciornis, the original nocturnal mollusk-eating bird, is a large sandpiper having convergent similarity to rails. True rails occupy mainly marshlands of large islands and do not lose ability to flight. On small islets where there is lesser number of mammals, there are forest-dwelling kinds of rails. Anserine birds of Hawaii are rather numerous; the majority of their kinds represents ducks leading the traditional near-water habit of life. Some species of ducks and geese from North America and Eastern Asia winter on islands. Settled species include large flightless browsing birds – Hawaiian forest geese. Gallinaceous birds also are present at the archipelago: these are diverse “false pheasants”, descendants of American quails. They live in light forests and bushes, and also on hillsides. Among carnivorous birds there is an original flightless species of harriers – kuahana, the bird hunting large ground-dwelling vertebrates. At sea coasts ethereal kites nest; they search for food in sea and in littoral zone. Neopueo, the descendant of harriers leading crepuscular habit of life and eating insects and small vertebrates, represents an interesting example of convergence with owls. For islands also true owls are characteristic: there are some small species of owls eating insects almost exclusively. They descend from one North American species settled to islands after the ending of human epoch. All pigeons of Hawaiian islands descend from some species introduced in human epoch. Among them various species living in forest canopy are usual – these forms descend from Chinese (spotted) dove. In Alpine areas there are species of pigeons feeding on the ground and nesting in caves and niches of rocks – these are representatives of another genealogical line of pigeons descending from rock dove. Also on islands there is an endemic family of false dodos, which is presented by large flightless paradodo living in bush thickets; it is also the descendant of rock dove. Songbirds are presented on islands by a plenty of kinds; the part of them descends from the ancestors introduced by people. From Japanese white-eye the separate new family descended – Hawaiian honey birds (Melisugornitidae) specialized in feeding on nectar. Insect-eating birds are presented mainly by species of starling family. Among them there are specialized forms – snail-eating Hawaiian hookbill and Hawaiian ant starling eating ground-dwelling insects. Descendants of introduced common myna occupy an ecological niche of corvids – these are medium-sized omnivorous birds eating insects and small vertebrates. Finches and weaverbirds are main groups of plant-eating birds of forest canopy. Among them there is false crossbill – the specialized form feeding on seeds of conifers. Palm hardbill is another example of specialization to seed eating. The original predatory bird of the archipelago is the eagleraven of endemic species and genus related to Asian forms.
Due to tropical climate reptiles prosper at the archipelago and their species variety is great. Ground-dwelling reptiles of islands descend exclusively from the kinds imported by people in historical epoch. Tortoises are absent at Hawaii, but large sea-dwelling bat turtles nest on islands; for egg laying they enter the rivers of islands and penetrate deep into the forest. Also soft-shelled turtles live in fresh water; they descend from Chinese softshell turtle introduced in human epoch. Among them there are small insect-eating forms and one large kind having convergent similarity to African crocoturtle and eating large vertebrates. Among lizards there are various geckos and descendants of Anolis lizards. Geckos are mainly arboreal and rock-climbing, mainly insectivorous forms. Among descendants of Anolis there are some tree-climbing herbivorous species and one specialized form feeding on ground snails. The fauna of snakes on Hawaii is rather poor despite of tropical climate. For forest soil underground crown-tailed snake is characteristic; it is large kind of blind snakes eating small vertebrates. On various islands there are some small species of blind snakes eating insects and differing only a little from each other externally.
Amphibians of Hawaiian islands are presented exclusively by descendants of introduced forms: before the appearing of people amphibians were not found on these islands. On archipelago there are representatives of three genealogical lines descending from cane toad, North American bull frog and Cuban tree frog. Hawaiian toads live mainly on land – in wood litter, in bush and in mountain areas, including the areas of cool climate. Tree frogs are exclusively forest-dwelling warm-loving forms living in forest canopy and on trunks of large trees. Descendants of bull frog are aquatic and semi-aquatic forms inhabiting freshwater reservoirs and damp ground habitats.
In Neocene freshwater fishes of Hawaiian islands are presented much richier, rather than before human epoch. Almost all of them are descendants of freshwater fishes introduced by people. Small viviparous fishes descending from poecilias and swordtails by natural hybridization of introduced forms are most numerous. Due to ability to live in sea water they had crossed passages between islands and had occupied the whole archipelago. The descendant of introduced Gambusia had turned to active top skimmer predator. Small catfishes of family Ictaluridae (of North American origin) and some kinds of suckermouth catfishes (descendants of the species Hypostomus watwata of South American origins) also live in fresh water. Cichlids are widely settled; these ones are descendants of African tilapias and South American cichlasomas. Sea fishes come into the rivers and live in fresh water for any time. Among them gobies and some eleotrids inhabited rivers of islands in natural way after the formation of new complex of freshwater fishes species.
Tropical climate and plentiful vegetation promote the existence of rich fauna of terrestrial invertebrates. Insects of archipelago are very diverse, and the part of their species descends from the ancestors introduced by people in historical epoch. Odonates are very diverse, both dragonflies and damselflies are equally submitted. Almost all these insects descend from local species of human epoch or had got ot the islands only after human extinction. Sawlegs, large predatory grasshoppers, represent the characteristic group of insects. At Hawaii they are smaller, rather than on other islands, where the number of mammals is less, but the species variety is much greater. Among Hawaiian sawlegs there are flightless forms endemic for different islands and mountain valleys. Bugs are presented by numerous predatory and plant-sucking species among which there are the forms able to digest latex. Water striders (Gerridae) live in fresh water. Many species of ants are characteristic representatives of insects – all of them are descendants of introduced species. Monstrous ant is one of the largest kinds at the archipelago; it is dangerous even for small vertebrates. Social wasps, descendants of European wasps introduced to the islands, form giant perennial colonies. Some species of these wasps attack small vertebrates and gather carrion. Among predatory beetles there are small water beetles appeared at the islands only after human epoch. Fireflies are numerous and especially diverse in forests; among them ecological analogues of ground beetles, rove beetles and carrion beetles had evolved. Among beetles of Polyphaga suborder capricorn beetles and leaf beetles are diverse. Moths and hawk moths are various; they reach great size and are frequently specialized to pollination of strict number of plant species. Butterflies of Hawaiian islands are presented by unnumerous nymphalids, pierids and milkweed butterflies (descendants of North American monarch settled to the islands in natural way). Due to the people mosquitoes appeared on islands; they survived in epoch of mass extinction and had formed many new species in Neocene. Among them the specialized kinds had appeared, including ones eating blood of snails and products of decomposition of corpses.
In arachnid fauna many changes had taken place. The majority of endemics lived on islands up to human appearing had died out, not having left descendants. The basis of arachnid fauna is made of descendants of the species introduced to islands, and the species arrived to islands in natural way in early Neocene. Among the Hawaiian spiders there are wolf spiders (ground-dwelling and semi-aquatic forms) and jumping spiders (mainly arboreal forms). Orb-web spiders living in forests and bushes are very diverse.
Due to tropical climate at Hawaii ground-dwelling crabs inhabiting forests, marshes and river valleys are diverse. Among them there are scavengers, predators, and even consumers of dung of local vertebrates. The majority of crabs moves to the sea for breeding, but there are few species able to pass a complete cycle of development in fresh water. Crayfishes are absent, but shrimps are diverse. The majority of their species lives in river mouths and migrates to sea water for spawning, but there are some small local species turned to true freshwater inhabitants and lost the metamorphosis.
Before human epoch on Hawaiian islands many species of terrestrial gastropods lived. After the arrival of people to the islands many endemic species had disappeared because of destruction of habitats or competition to naturalized species of snails. Neocene ground snails of Hawaiian islands are exclusively the descendants of forms introduced by people, or the species appeared on islands only after human disappearance. Some of Hawaiian snails lead a predatory way of life, and there are even the forms developed the symbiotic relations to ants. There are also “Hawaiian pond snails” – small forms descending from introduced giant Achatina snail and returned to aquatic habit of life. In river mouths neritinas live – the gastropods of sea origin able to live in fresh water temporarily. In lower reaches of rivers few species of bivalves live, being able to exist in freshened water.
|Hawaii, characteristic kinds of plant communities, various species of plants. (not translated, Russian version only!)|
|Hawaii - animals of rainforest. (not translated, Russian version only!)|
|The terror of silver forest||Biocenosis of Hawaiian mountain forest - invertebrates and small vertebrates. (not translated, Russian version only!)|
In Neocene the southern part of Pacific ocean still remains
the largest congestion of islands on the Earth – here there are more than 15
thousand of them. Islands of Oceania are grouped in three large areas: Melanesia
in the west of Pacific ocean, Micronesia in northwest and Polynesia in the east.
In each of these areas the certain changes took place since the end of Holocene.
So, Melanesia had lost a part of islands (namely northern part of Solomon islands)
due to their connection to Meganesia. Micronesia and Polynesia in human epoch
included set of islands of coral and volcanic origin scattered on open spaces
of Pacific ocean, mainly, in tropics where reef-building corals could grow.
At the boundary of Holocene and Neocene reef-building corals had died out because
of global ecological crisis, and the significant number of coral islands had
disappeared. Another reason of disappearance of the part of low islands is their
flooding owing to increase of level of World ocean connected to Neocene climate
warming and thawing of polar icecaps. In Neocene, when the new fauna of reef-building
animals had developed, small islands of reef origins have appeared again approximately
in the same places where there were coral islands before, and even have grown
up on their old limestone bases.
Volcanic islands are located mainly in places of joint of lithospheric plates – Pacific, Indian, Australian and Philipino plates. Volcanic islands are higher and have the greater area. Frequently there are erupting or inactive volcanos on them.
Though the majority of islands of Oceania is of coral and volcanic origin, there is one exception: New Caledonia island in Melanesia, being a splinter of ancient continent. The climate of islands of Oceania as a whole is identical, tropical, differing only in amount of precipitation. Only on some southern islands the tropical climate is replaced by subtropical one. For many islands of Oceania destructive typhoons and hurricanes are characteristic.
Fresh-water reservoirs on islands are absent more often or represent shallow streams and lakes on largest islands. On small islands rain represents the only source of fresh water.
The review is written at the participation of Simon, the forum member.
The flora of Oceania is rather poor in comparison with continental
one. Here many groups of plants are absent, especially ones settling with the
help of ground-dwelling animals. The majority of species of local flora is settled
with the help of wind or birds, and also with the help of ocean currents. Human
activity in far past made a great contribution to formation of island flora
– the part of local plants represents the descendants of cultural plants of
The most typical kind of plant community is mangrove forest formed by trees of several species belonging to several different families. The special kind of palm trees – sea coconut palm having creeping trunks and stilted roots reached the significant distribution in Oceania (especially in Polynesia). This kind of plants forms extended thickets at the sea shoaliness. In coastal areas of islands extensive thickets are formed of palm trees of several species, and also of Pandanus.
On low islands of reef origin subsoil waters are salty; in such places only salt-resistant plants can grow, and also small bushes and grassy plants which roots are above the level of subsoil waters. Flora of high islands of volcanic origin is much more diverse. Far from the coast on raised areas rich evergreen forests grow. They are formed by the species appeared at the islands in natural way, and also by descendants of introduced species. On damaged areas of forest there is a pioneer vegetation including fast-growing kinds of banana and papaya. They are replaced by perennial bushes of families Nyctaginaceae (Pisonia known from human epoch) and Malvaceae (Hibiscus of several local species). Some bushes grow later as undersized trees. Trees of native flora belong to spurges, dogbane and some other families. Among treelike plants of Oceania there are representatives of Asteraceae and Campanulaceae families. In Polynesian forests descendants of flora introduced by people are mango, Casuarina, descendants of breadfruit tree and escaped citrus species. Species of Miconia (velvet tree of Melastomataceae family) widely settled in human epoch and hardly eradicated are very usual on islands. There is larger number of descendants of native flora among bushes and grassy plants.
On old islands of volcanic origin there are plants of bromeliad family – the descendants of cultural pineapple with small compound fruits and rosettes of long leaves. Everywhere in Oceania descendants of taro (Alocasia) grow, reaching especial development in marshes of some islands. Descendants of sweet potato representing creeping tuberous plants also are usual. Among grassy plants there are some kinds of orchids, including descendants of vanilla – large lianes and semi-epiphytes.
Ferns are especially numerous on islands where rich humid forests grow. The majority of their species is epiphytic ones, and some ones grow in underbrush, forming extensive thickets due to shadow-resistance. In southern part of Oceania there are some species of tree ferns of New Zealand origin.
The fauna of islands of Oceania is poor in ground animals because
of geographical features of this region. Remoteness from continents and the
great distances separating islands interfere with settling of islands by the
majority of groups of animals. Prominent feature of zoogeography of Oceania
is the decreasing of the number of animal taxa at the movement to the east.
Mammals are very rare on islands. At the majority of islands bats and fruit bats live exclusively, being able to settle independently. On old strong islands of volcanic origin rodents live; these are numerous descendants of rats introduced in human epoch. From among carnivores on some islands cats, and on Fiji islands mongooses, descendants of the species kinds introduced by people live. On some islands of Melanesia dwarf descendants of feral pigs had survived.
Fauna of birds of Oceania is much more diverse, rather than mammalian one. On islands the most diverse of all are birds of sea origin – tubenoses, pelecaniforms, gulls and terns. Ethereal kites, or seraphimornitids, the long-winged sea birds adapted to distant flights and catching of fish at flight represent the unusual group of sea birds. Sandpipers are presented mainly by migrating forms, but on the islands lacking mammals endemic species of sandpipers of plover and scolopacid families live. On islands of Oceania there are many wintering kinds of sea birds from North America and Asia.
Ground-dwelling birds are more diverse on islands where ground mammals are absent. Swamphens and rails had widely settled on islands again, especially on newly formed ones where there are no ground-dwelling predators. As against human epoch, they have kept ability to fly and skills of self-defense on the most part of islands. Some rails have got ability to hunt rats. Ciconiiforms (stork birds) are presented by widespread species of herons. On some islands herons have formed endemic species. On many islands ducks live, including some local species. From among gallinaceous birds in the west of Polynesia and in Melanesia descendants of feral domestic chicken live, including rather large ones, and there are also descendants of quails. In some parts of Melanesia descendants of megapods exist. Birds of prey are not numerous: in forests of Micronesia, Melanesia and in the western Polynesia endemic forms of hawks and small falcons live, and harriers are settled wider. On islands pigeons are usual; there are some species of small endemic coorrows. On some islands there are some species of very large badly flying ground-dwelling pigeons. One more characteristic group of Polynesian birds is parrot order. In human epoch many species of these birds had died out, but in Neocene some Asian and Australian species had re-occupied islands, having evolved to many endemic species. On islands of Melanesia boobook owls (Ninox-related genera) live, and farther to the east barn owls are widespread. Coraciiforms are presented by several kinds of kingfishers forming endemic forms of species and subspecies rank on remote islands. In Micronesia in addition to kingfishers bee-eaters and rollers (Eurystomus and allies) live. Representatives of nightjar order live in Melanesia, Micronesia and western Polynesia. Up to the east of Polynesia swifts and cuckooes are settled.
Islands are inhabited by numerous songbirds. Swallows, starlings (including descendants of European starlings and mynas introduced by people), marsh-warblers (Acrocephalidae), white-eyes, estrildid finches, honeyeaters, Old World flycatchers (and families related to them like fantails, monarch flycatchers, Australasian robins and others) are most widely settled. Birds of cuckooshrike, drongos, thrush and some other families have less wide area. Descendants of the species introduced by people are bulbuls and weaverbirds (descending from house sparrows). Corvids have rather wide area; they descend from South Asian and Australian species, and also from New Caledonian crows. Asian magpies also managed to settle at some islands of Oceania and formed endemic species.
The variety of reptiles on islands is not so great, that is connected mainly to difficulties of moving to islands. On the most part of islands small lizards – geckos and skinks – live. Neighbourly to mammals mobile and small species live mainly, and on islands lacking them larger kinds of these lizards live. Endemic iguanas of Fiji islands do not have any descendants in Neocene. On some islands of Micronesia monitor lizards live. In snake suborder sea snakes are numerous, and at the north of Melanesia snakes descending from local forms live. Existence of ground-dwelling snakes on some other islands of Pacific is connected to human activity: brown snakes had been introduced to Guam, and on Fiji and some other islands blind snakes had appeared in the same way. Sharkodile, one of last crocodile species, the largest Neocene representative of this order, is also the largest reptile of Polynesia. It arranges nests on Tonga islands where the ground is warmed up by volcanic heat. Also on islands of southern part of Pacific ocean there are nesting places of duplication sea-dwelling bat turtles.
Amphibians almost absent on islands of Oceania. On large islands (for example, on Fiji) descendants of the species introduced by people live: tree frogs (descendants of Australian forms) and toads (descendants of cane toad). On some islands amphibians appeared only after human extinction, for example, as eggs stuck to paws of birds, or on rafts of plant material.
Freshwater fishes are absent, but some species of sea fishes come into fresh water.
Due to a tropical climate the fauna of invertebrates is rich and diverse. Among island forms large predatory grasshoppers, sawlegs able to attack even small mammals, are remarkable. There are some species of these insects able to fly from island to another one, and also a number of flightless species reaching greater size. On islands located closer to continents, stick insects and bugs live, frequently having freakish appearance. Common inhabitants of islands of Polynesia are beetles and butterflies among which there is a lot of endemic species. Dipterans are diverse and inhabit in fact all islands. Larvae of some species have a great importance as soil-formers.
The part of invertebrates has sea origin: these are crabs and other crustaceans. Ground crabs and hermit crabs are widespread due to presence of stage of floating larva in their life cycle. Crabs are small predators and hunt local insects, rodents and tiny birds, and hermit crabs gather decaying parts of plant and animal origin.
Ground snails are presented by plenty of endemic species. On each island or archipelago there is a clearly expressed group of species related to each other and representing the result of only successful attempt of colonization of the given territory. Obviously, their moving took place on floating trunks of trees or on legs and plumage of birds. On large islands descendants of Achatina snails introduced by people live. Freshwater snails are absent.
The review is written at participation of Simon, the forum member.
|Tropical part of Pacific ocean, Tonga island|
During Holocene and Neocene Galapagos islands remained a center
of volcanic activity because of gradual movement of Nasca plate moving by its
edge under South American plate. Often volcano eruptions and earthquakes have
caused the change of geography of islands. Some small islets of the archipelago
have sunk, and the part of young islands having higher volcanic activity (Isabela,
Fernandina, Santiago and Santa Cruz) had merged together. In Neocene on islands
earthquakes are frequent, and some volcanos erupt regularly. Mountains of islands
became much higher and have the important function of condensers of air moisture.
The climate of islands is tropical, but due to the shifting of South America to the south it began a little more arid. The climate substantially depends on cold Peru (Humboldt) current. Contrast of temperatures between sea and land results in formation of morning fogs in coastal areas of islands. On islands there are no rivers, and shallow ponds in lowlands are filled only with rain water.
In some mountain valleys protected from wind there is a humid microclimate due to bogs and small lakes forming there.
In connection with arid climate of islands local vegetation
shows features of the adaptation to intensive absorption and stocking of water.
The vegetation of coastal areas is adapted to catching fog moisture: coastal
trees and bushes (mainly of bean family) have the leaves able to fold lengthways.
In the morning such leaves are opened and absorb drops of dew, and in day time
they close, protecting the upper side from the sun. At other plants the leaf
rosette is opened at night, absorbing moisture, and closes in the afternoon,
being under protection of rough and prickly external leaves. Coastal species
of cactuses absorb water with rich downiness on stalk.
In arid areas of large islands, and also on small low islands the complex of tropical light forests is formed, where bean plants (descendants of introduced carob tree), treelike Asteraceae and cactuses prevail. On sites with poor soil continuous thickets of graminoids descended from Pennisetum grass introduced in human epoch are formed.
Plants of bean family appeared on islands with the help of people (carob tree) or had settled from continent in natural way by sea only in early Neocene. They have reached success in struggle for existence due to presence of the rodents becoming the carriers of their large seeds. Treelike bean plants of Galapagos islands frequently form the life form of “the bottle tree” with friable water-stocking core. Aster plants are remarkable with numerous prickles covering a stalk and main leaf nerves, especially at young age. Cactuses (Cereus and Opuntia) form large thickets due to ability to vegetative breeding.
Mountain areas of islands are more humid; rich forests with dense canopy grow here. Here plant species are related frequently to kinds of dry light forests, but have less advanced water-stocking tissues, large leaves and small prickles. Among local cactuses Equadopuntia is remarkable – it is a treelike cactus with casting annual shoots. In forests there is very poisonous manchineel tree of genus Hippomane – the descendant of the species existed on islands in human epoch. In damp mountain valleys ferns grow. Epyphitic plants are not numerous – these are some species of ferns and bromeliads.
The important component of forests of Galapagos isands is a set of palm species settled on islands by sea. They form small thickets or grow as single trees.
On coastal shoalinesses mangrove forests grow. At the coast also there are thickets of sea coconut palm (the archipelago is located at the eastern edge of an area of this palm).
In human epoch endemic flora and fauna received strong impact
– people had introduced a plenty of species of ground-dwelling mammals, both
herbivorous and predatory. Due to nature protection actions feral goats and
dogs were exterminated on islands, but rats have remained, bred in great number
and evolved further, having formed some new species.
Among mammals of Galapagos islands the descendants of rats leading different ways of life and adapted for various habitat conditions are most diverse. Large and slow species of rats eats firm seeds of palms and bean plants, being the analogue of Hawaiian kapo. Small ground-dwelling and arboreal kinds eat seeds and insects. From among predators on islands the descendants of domestic cats survived and have formed some kinds. One of them is small, tree-climbing and similar to marten, and another one is larger ground-dwelling form. On different islands rat species evolve the local forms differing in size and body proportions.
Pigs have remained in fauna of islands, having formed some dwarf island forms similar to dwarf species of Crimea and Mauritius islands.
The fauna of birds of archipelago is very diverse, but differs from the one existed in human epoch. On islands herons of several species live, including one small and short-legged forest-dwelling species similar to rails and hunting rodents and crabs. These birds limit the breeding of rodents and promote maintenance of biological balance on islands. Large herons eat mainly insects and rodents. One more kind of herons lives in mangrove thickets and searches for food in littoral zone.
Sea birds are diverse: on islands there are various species of gulls, including nocturnal seagull hiding in day time in refuges among rocks. Many species of terns nest on trees for protection against ground predators. On islands large gannets lost the ability to flight nest. They form dense rookeries on islands lacking of mammals. At the coasts sandpipers are diverse, including migrating ones flying for wintering from North America.
Other migrants, of the southern origin, are Pacific sea swans. Ducks are rare inhabitants of islands; these are mainly casually appearing and migrating species. It takes place because of small number of freshwater reservoirs suitable for their life.
From birds of prey on islands one species of true owls and caracara of local endemic species are found.
Parrots, trogons, coraciiforms and woodpeckers are absent on Galapagos islands.
Passerine birds are not numerous in comparison with South American ones. Among suboscines there are some species of tyrant flycatchers. Songbirds are more numerous and are presented by several families. As well as in human epoch islands are inhabited by various finches, the direct descendants of ground finches of human epoch. They also occupy various ecological niches and differ in anatomy and behaviour. Among them there is a species turned to brood parasite, and also night vampire – an original haematophagous bird. From among other songbirds on islands mockingbirds and tanagers live.
The fauna of reptiles had undergone significant changes in comparison with human epoch. Elephant tortoises, the sign group of inhabitants of Galapagos islands, are kept in very little number – the significant number of their subspecies had died out in human epoch or soon after it because of climatic changes and the competition to ground-dwelling mammals. One of few representatives of elephant tortoises is spike-headed tortoise. Besides it on islands there are some more species differing in size and the shape of carapace. Squamates are presented by geckos and several kinds of Teiidae, and also by small ground-dwelling iguanas settled on islands after the ending of human epoch. Large land iguanas Conolophus had died out and marine iguanas became rarer. These reptiles live on many islands of archipelago, but for breeding migrate to small islands lack of mammals.
Amphibians and true freshwater fishes are absent on archipelago.
Invertebrates of Galapagos islands are not very diverse compared to fauna of South America. Islands had never connected to the continent, and the local fauna is made of two components: of descendants of the species appeared on islands in different time in natural way, and of descendants of the species introduced in historical epoch.
Among insects of archipelago there is a lot of descendants of introduced species. The majority of local cockroaches represents small-sized species, descendants of the introduced German cockroach. The variety of beetles is insignificant; among them there are some species of capricorn beetles and leaf beetles. In human epoch water scavenging beetles inhabiting local ponds had got on islands. There are some species of ladybugs which colouring varies on various islands. In human epoch various scale insects have got on islands with cultural plants; their descendants make food of some island ladybugs. Among bugs there are some kinds of schield bugs and predatory bugs. Parasitic bugs living in coastal zone near to bird rookeries are descendants of bed bug of human epoch. Lepidopterans have rather small species variety; among them there are no specialized forms. There are some species of milkweed butterflies, owlet moths, inchworms and saturniids. Some butterflies formed symbiosis with ants rearing and protecting their larvae. Hymenopterans are presented by wasps and ants. Polistes wasps, descendants of the species introduced in human epoch, form small colonies on trees. In forests there are also large colonies of paper wasps, also descendants of the species introduced in human epoch. Everywhere on islands predatory kinds of ants are common – these are descendants of fire ants introduced by people. The variety of dipterans is very small; among them there are blood-sucking kinds (horseflies and mosquitoes) feeding on blood of warm-blooded animals, and some kinds feeding on nectar and organic remains.
From among other arthropods on islands there are the descendants of the local species of scolopender centipede inhabited islands in human epoch. Also there are some species of orb-web spiders.
From among arthropods of sea origin on islands there are some species of crabs of grapsid family migrating to the sea for breeding.
Ground-dwelling snails are presented by several small species.
Islands of Eonesia
As a result of proceeding volcanic activity along the line
of East Pacific Rise (between Pacific and Cocos plates, and further to the south
between Pacific and Nazca ones) in Neocene the new, but for the present faltering
chain of islands had appeared. It stretches from California to the south aside
Easter island almost in meridional direction. In human epoch this area was a
place of great volcanic activity: a plenty of underwater hydrothermal springs
and “black smokers” was located along it. In Neocene underwater mountain ridges
had reached water surface in many areas and had formed the set of islands named
Eonesia. “Eos” means “dawn” and also “early” in Greek, that specifies simultaneously
the location of islands in eastern part of Pacific ocean, and also their young
age in geological respect. Because of fast movement of oceanic plates the formation
of islands took place rather slowly, and islands are divided into three groups,
distant rather far from each other. At the most part of archipelago between
them and coast of America there is no other land.
To the south from California (turned to island in Neocene) there is a group of Atarapa islands. These are rather small volcanic islands between which there are shallows and underwater mountains. Name “Atarapa” occurs from the name of Polynesian goddess of dawn as islands are located in the eastern part of Pacific ocean.
The large group of islands, Fisaga islands (in Polynesian mythology it is the name of sea breeze god), is a little bit to the north of equator, at the joint of three lithospheric plates: Pacific, Cocos and Nazca plates. The land nearest to them is Galapagos archipelago. Volcanic activity is the highest here.
Some small islands, Burotu islands (paradise islands in native Fiji mythology), are scattered in Pacific ocean as the chain stretched from equator up to Easter island which is the most southern point of Eonesia islands.
As all islands have a volcanic origin, volcanic activity is expressed on them in greater or lesser degree: there are earthquakes, hot springs and more or less regular eruptions of volcanos there. All islands are located in tropical latitudes, therefore their climate is tropical everywhere, with small distinctions in precipitation level. Northern part of Eonesia islands is located near the American coast, and the close distance to landmass has great influence to the climate of islands: the precipitation level here varies depending on seasons, and in winter from the land cool dry wind blows. Moving above the ocean it has no time to receive enough moisture, therefore in winter weather at Atarapa islands is drier, than in summer.
The group of Fisaga islands is located much farther from the continent, and their climate entirely depends on ocean. It is equal, with a plenty of precipitation promoting development of vegetation.
Burotu islands also differ have tropical marine climate with high air humidity and plenty of precipitation.
All Eonesia islands are surrounded with a zone of reeves formed of molluscs, worms and sponges. At the north reeves are formed by a small number of species, and algae and sea grasses play the important role there, and at the equator and in southern hemisphere reeves are formed almost exclusively by reef-building animals, and islands of volcanic origin are surrounded with wide strip of shallows and islets of reef origin.
A species variety of plants growing on islands depends directly
on distance up to the nearest land, and also on latitude.
The group of Atarapa islands shows the species structure of flora close to North American one. Here there are descendants of deciduous and coniferous trees able to settle with the help of wind and birds and also to endure winter dryness. On heights of islands pines grow, and dry coastal areas are occupied by thickets of cactuses of several kinds got here, obviously, from California island due to birds. Deciduous trees and evergreen bushes grow mainly in mountain valleys where the humid microclimate is developed locally.
Fisaga islands show rich flora. It takes place due to the location of islands in the zone of equatorial climate promoting the development of evergreen broadleaf forests. At the coast of islands there are thickets of sea coconut palm forming a natural breakwater, and some species of mangrove trees settling between land and thickets of sea coconut paln. Due to birds seeds of trees of several families have got on islands, and the wind brought spores of ferns. In species structure of flora of Fisaga islands the influence of Galapagos islands – the nearest land – is appreciable. In mountain areas of islands on dry soils and stony taluses cactuses grow, and in forests trees of species and genera close to Galapagos islands natives grow. Influence of flora of Oceania is shown in presence of some common species, including descendants of velvet tree (Miconia).
The flora of Burotu islands as a whole is close to flora of Oceania, differing at the level of close species and genera. On islands palm trees and Pandanus dominate; some kinds of plants have appeared on islands due to bats. Among grassy plants the unusual detail is the presence of the reed being the descendant of the species grown at Titicaca lake in human epoch. This reed had settled on Burotu islands to the north from Easter island, where, most likely, it was introduced by people.
As Eonesia islands had formed only after the ending of human
epoch, their settling by animals proceeded in natural way. In taxonomic structure
the fauna of islands is similar to typical fauna of Holocene islands before
their human colonization.
The number of mammals on Eonesia islands is very small. On Atarapa islands some species of rodents and one kind of rabbits live; their ancestors have got there from California island. Also chiropterans of North American origin, both settled and migrating live here. On Fisaga and Burotu archipelagoes mammal are presented only by chiropterans of Central and South American origins which moving took place from the north to the south. The majority of species of these animals still represents insectivorous or frugivorous forms. One species on Fisaga islands became large one and had substantially lost ability to fly. This one swarms up tree branches and only glides from tree to tree, but runs and walks on the ground well, supporting on large thumb of wing.
Due to absence of the competition with mammals the fauna of birds of Eonesia islands includes some large and flightless species. On all islands sea birds settle: gulls and sandpipers, and also tubenoses – petrels and false albatrosses related to large subantarctic kind, but smaller. Due to absence of mammals many species of birds lost ability to fly: on Burotu islands some subspecies of flightless gannets live, and on Fisaga archipelago large flightless cormorant is found. On Atarapa islands the heron lives, which had lost ability to fly and searches for food on land. Cuckooes and some species of parakeets of Central American origins live in that place also. Predatory birds of Atarapa islands are presented by one small species of true owl, large barn owl and large kite frequently searching for food on the ground. In coastal thickets one species of ethereal kites nests. On these islands gallinaceous birds live – New World quails moved here from California island. Songbirds of Atarapa islands are diverse; their fauna replenished for a long time due to migrating species or casual settlers from North America. Cardinals, tanagers, finches, grackles and corvids live here. From among migrating species swallows and swifts are characteristic.
Due to softer and more humid climate the vegetation of Fisaga islands is much more plentiful, that favours a species variety of birds. On Fisaga islands sea birds form numerous rookeries; there are some endemic species of sandpipers, gulls and terns here. There is also the local heron species which had settled on all islands of archipelago and had kept ability to flight. On islands large ducks live; they are related to mallards of human epoch, have no ability to fly and are the largest herbivorous birds of islands. Among forest birds of Fisaga islands there are trogons descended from the Central American forms; some species of these birds are closely related to each other and represent the result of one successful attempt of colonization of islands. Also on Fisaga islands some species of parrots and large forest-dwelling pigeons live. Passerine birds are presented by several species of tanagers, expressing the phenomenon of adaptive radiation - among them specialized frugivorous, insectivorous and nectar-eating species had evolved. Besides to them on islands some species of mockingbirds and thrushes live. On Fisaga islands one endemic settled species of swallows lives, and there are also some migrating ones.
Burotu islands, the archipelago most removed from continents, have the typical island fauna including highly specialized endemic species. Besides sea birds on islands large ground-dwelling pigeons feeding on fruits and seeds live. In forests of islands large flightless (but climbing up trees well) parakeets live, being the original ecological analogues of monkeys. Also on Burotu islands some species of flightless sandpipers similar to kiwi are found; these are forms of American origin which ancestors flied to the islands for wintering. The main predator of islands is badly flying ground-dwelling gull lacking palamas between toes. Songbirds of Burotu islands are not numerous and belong to tanager and finch families (closely related to species of Galapagos islands).
Reptiles of Eonesia islands show the decrease of the variety farther from continents and at the movement from the north on the south that is connected to increase of difficulty of moving to the islands.
Atarapa islands have the richest fauna of reptiles that may be explained by the close distance to the continent. Here small iguanas and geckos live, and also large snake-looking slowworm is found. Also on this archipelago tortoises live – these are the descendants of box turtles (Terrapene) got here from North America. Because of the competition to birds and mammals the fauna of Atarapa islands does not have giant representatives of reptiles characteristic for island faunae.
On Fisaga islands large ground skink of Central American origin lives, and also there are small anoles of several related species. Besides to them on islands large omnivorous ground-dwelling iguana lives and large monitor-looking representative of teiids is found, being the main ground predator of island.
Burotu islands are remarkable in poor fauna of reptiles. Here only few small parthenogenetic lizards of teiid family of South American origin live, being settled through Galapagos islands.
Amphibians and freshwater fishes are absent on all islands.
Fauna of invertebrates of Eonesia islands is rather poor, that takes place due to inaccessibility of islands for ground-dwelling invertebrates.
The fauna of Atarapa islands is the most diverse at the level of orders and families, but on Fisaga and Burotu islands the diversity of species of insects belonging to few families is greater. For islands of Pacific ocean as a whole the family of sawlegs – large predatory orthopters – is characteristic. They are widespread everywhere, forming many flightless species on islands. Dragonflies inhabit large islands where there are constant sources of fresh water. They form many endemic species on Atarapa and Fisaga islands. From among other well flying insects on islands butterflies of nymphalid and swallowtail families and also various moth and owlet moths are present. Beetles are numerous; large forms having no ability to fly are frequently found on islands. There are representatives of weevils, click beetles, capricorn and scarabeid beetle families. Larvae of click beetles have the important role in soil-making. From among predatory beetles on islands water beetles, rove beetles and fireflies are found. On all islands of Eonesia ants live; they are more numerous on Atarapa and Fisaga archipelagoes, whence the moving of these insects to the south had taken place.
Arachnids of islands are presented by spiders and mites. Myriapods live only on Atarapa (millipedes and scolopenders) and Fisaga islands (scolopenders only). Burotu islands are inaccessible to this group of arthropods because of remoteness from continent and from each other.
Crabs represent the important component of island fauna of ground-dwelling arthropods. The majority of species of these crustaceans is common for all islands because larvae of these animals are carrying by currents, but on Atarapa islands the fauna of ground-dwelling crustaceans is much poorer, than at the south. Obviously, it is connected to dry winter and rich fauna of ground-dwelling vertebrates. On Fisaga and Burotu islands in addition to crabs ground-dwelling hermit crabs live.
Snails are numerous on Atarapa islands, the land most closed to the continent and to California island. At the moving to the south the variety of snails at the genera level decreases. Burotu islands are inhabited by snails of the only genus, but of some local species endemic for each island.
Earthworms live only on Atarapa islands where they appeared from the continent, obviously, with the help of birds.
|Indian ocean - islands and island life.|
|Indian ocean - sea shallows|
Mauritius and Mascarene Islands
In Neocene Mascarene islands had moved a little to the east
because of movement of tectonic plates, but in geographical respect this archipelago
has a little changed as a whole in comparison with human epoch. It still consists
of several tens islands, largest of which are Mauritius, Reunion and Rodriguez.
Being of volcanic origin, these islands have not collapsed like the majority
of small islands of Indian ocean known in human epoch. However volcanic activity
had not expressed on them since the time of extinction of mankind. Some islands
of this archipelago are created by reef-building organisms only after disappearance
The relief of islands is smoothed by erosion, for large islands extensive inland plateaus and low mountain tops are characteristic. Inland plateaus are surrounded with coastal plains.
Climate of Mascarene islands is tropical with plentiful precipitation. Seasonal changes of the climate are expressed poorly (long rainseason and short-term rather dry season exist), but cyclones originating in Indian ocean in the beginning of the year render the great influence to the weather.
From highlands of large islands numerous small streams and rivers flow down, and also shallow lakes and marshes exist. On many smaller islands there are only temporary reservoirs filled with water only after rain.
The review is written by Simon, the forum member.
The flora of islands has undergone sharp changes since human
epoch. In historical time the extensive extinction of species of local flora
took place due to the activity of introduced species of herbivores (hoofed mammals)
and the introducing of a plenty of alien kinds of plants. At one stage of development
of new flora the complete extinction of the old flora evolved before historical
colonization happened. At this time islands had been covered with light forests
where descendants of introduced animals wandered, preventing the development
of continuous tropical forest. Later, when herbivores decreased in size in great
degree, the flora of islands restored gradually, but it included exclusively
descendants of introduced species of plants managed to sustain trampling and
grazing caused by ungulates. Treelike descendants of grassy plants give an originality
to Mauritian flora; one of such species is Mauritian false-berry tree. Characteristic
representatives of flora of islands include treelike spurges with caustic latex,
and also treelike representatives of Asteraceae. On islands there are some species
of begonia trees.
On highlands of large islands of Mascarene archipelago the tropical forest with dense canopy dominates. Tops of mountains are occupied by forest with rich fern underbrush. Coasts of islands are bordered by extensive bush thickets with small groups of palms. Palms are dominant plants on small islands. At coasts of large islands and almost on every small islet of archipelago there are mangrove forest areas.
Grassy plants of Mascarene islands are mainly aster plants and orchids among which there are epiphytic species. Also on islands graminoids grow; they are especially numerous in mountain areas where they form a zone of savanna-like vegetation in dry areas.
The fauna of Mascarene islands does not show the plenty of
the species, but the overwhelming majority of them is endemic. Native fauna
had died out almost completely because of hunting, habitat destruction and negative
influence of the species introduced by people. After the extinction of mankind
the restoration of fauna proceeded due to descendants of the introduced kinds,
and also to later migrants from Africa, from Madagascar and partly from Southern
Asia. Only some species of reptiles and few species of birds descend from native
Chiropterans are the only group of mammals of Mascarene islands which had reached the archipelago independently. Flying foxes of some endemic species form numerous colonies in forest areas. Also on archipelago true bats live, including the unusual very large gullbats hunting fish in the sea.
All other mammals of Mascarene islands descend from the species introduced by people intentionally or casually. On Mauritius island the niche of insectivorous mammals is occupied by descendants of tailless tenrec, and largest of them, Maurihystrix, resembles a porcupine more. Not numerous predatory mammals are presented by descendants of domestic cats and Asian mongooses. Felids have the top predator position in ecosystems, and mongooses are small specialized predators, for example, fish-eaters.
Descendants of rats and mice had occupied all Mascarene islands, except for the smallest and newly appeared ones. They are very diverse and occupy various ecological niches. Arboreal descendants of rats among which endemic Maurirattidae family had appeared, are most unusual ones. Among rats there are carnivorous forms, and also the forms able to gliding.
Hoofed mammals of Mascarene islands are not numerous and are remarkable in dwarf sizes. They descend from domestic pigs and коз.
On Mauritius the only species of primates on Mascarene islands lives – Mauritian dwarf macaque, the descendant of crab-eating macaque having very small size.
Birds of Mascarene islands are very diverse; the number of their species is greater, rather than at the end of human epoch. The sea birds nesting at the coast of the main islands or on small islets free of ground-dwelling mammals are most numerous. They are mainly tubenoses, pelecaniforms, gulls and terns. Also in sea unusual birds of prey of ethereal kite family. The most part of sandpipers belongs to migrating species staying on archipelago only for some days in year, but few species (plovers first of all) live here the year round.
There are only few freshwater birds on Mascarene archipelago. These are some small species of herons and ducks, some of which are endemic. Rails are more diverse, but they, except for several kinds similar to swamphens and coots are very secretive. Among them there are no flightless species. In coastal areas numerous gulls and sandpipers live.
Gallinaceous birds belong to pheasant family and descend from African species of quails and also from feral chicken. The largest bird of Mascarene archipelago – aepigallus reaching 150 cm in height – belongs to chicken birds.
From among birds of prey small falcons of African origin and one harrier species are characteristic.
Forest birds express great degree of endemism of species and genus level. Cuckooes, swifts and coraciiforms are presented by several species. Owls are descendants of migrants from Africa and from Madagascar; boobook owls are mainly insect-eating birds, and larger barn owls of endemic genus hunt vertebrates. Pigeons and parrots descend from the introduced forms, and also from Early Neocene migrants. Though some species of pigeons lead a ground way of life, among them there are no the kinds similar to extinct dodos. Small species of forest pigeons are remarkable in bright colouring; each large island has characteristic endemic species. Among parrots very atypical family of fishing parrots is remarkable. They eat fish and aquatic invertebrates and do not live outside Mascarene islands. “Typical” parrot species are also present in fauna of archipelago, but they are not numerous.
Passerine birds of Mascarene islands are rather diverse. Weaverbird, estrildid and white-eye families are presented by the greatest number of species. One species of weaverbirds is adapted to get insects from under tree bark and from soft wood. Also on islands representatives of such families, as swallows, cuckooshrikes, bulbuls, sylviids, monarch flycatchers and finches live. Starlings are presented by descendants of introduced Indian myna among which one large species occupies an ecological niche of crows. Except foe white-eyes, songbirds of Mascarene islands descend from the species introduced by people or from Early Neocene migrants.
Reptiles of Mascarenes belong to turtle and squamates orders. Tortoises of several species descend from Malagasy and African ancestors. Among the tortoises living on archipelago there are true giants like Mauritian armour-clad tortoise having carapace length up to 2 m. Lizards belong to gecko and skink families: their number is rather great, and many species descend from native ones. Some species of boid snakes are descendants of snakes from Madagascar; local snakes had died out in human epoch without any descendants.
Amphibians are almost completely absent on archipelago: the only exception is one frog species from Mauritius settled to the island, probably, as eggs on bird paws.
True freshwater fishes of Mascarene islands belong to separate species of cyprinid and osphronemid families. They are descendants of introduced fishes – goldfish and giant gourami. In addition to these species sea fishes come into the rivers of archipelago.
In conditions of tropical climate invertebrates reach a significant variety. Among insects butterflies and beetles are remarkable, including bright and large species characteristic for smaller islands. On large islands insects, as a rule, are smaller because of the competition and predatoriness on the part of mammals and more numerous birds. Some species of ants are endemic for archipelago. Spiders and scorpions are numerous. A plenty of endemic forms of ground snails is typical. Freshwater reservoirs are inhabited by shrimps and crabs of sea origin forming non-migrating freshwater subspecies, and ground-dwelling crabs live also in forests and at the coast.
The review is written by Simon, the forum member.
|Mauritius island and forest dwellers (not translated, Russian version only!)|
|Antarctica and subantarctic islands|
|Islands of Atlantic ocean|
|Islands of Pacific ocean|
|Islands of Indian ocean|