Tour to Neocene
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During Pleistocene and Holocene tropical rainforests of Amazon
basin repeatedly experienced both time of a flowering, and time of oppression.
In warm intirglacials the rainforest had occupied hardly probable half of continent,
and during ice ages its area was reduced up to several small "islands"
among dry and leaf-falling forests. Because of space accident of a late Holocene
practically all rainforests had disappeared from the face of the Earth. But
after consequences of global ecological crisis have ceased, life began to occupy
the left positions again. The great rivers of South America had lost a significant
part of tributaries, but had remained deep enough that around of them forests
had turned green again. After millions of years the Amason region became “the
green hell” again, rich and impassable, as before. And life to this world is
given by the river. It irrigates roots of trees, carries seeds and takes out
to the ocean thousand tons of sediments, increasing the area of continent. Amazon
river has shoaled also its channel was divided to two ones: old Amazon channel
and Hyppolite - the river current almost in parallel to Amazon.
The wood growing in Amason region, is a little bit drier, than was before: under
pressure of Nasca plate the South-American plate had bent aside Atlantic, and
rivers flow to the sea faster, not winding on plain. But in country between
Amazon and Hyppolite rivers wood is so damp, as before. Trees stand by roots
in seldom drying up swamp, therefore the majority of tetrapod animals inhabits
forest canopy at height 20 - 30 meters above the ground. Lianas are stretched
between trees. Their stalks are thick and strong, lignescent good, therefore
in forest canopy even the large animal can move freely.
Plant practically from any botanic family can become liana. On one of thickest
lianas having wide triangular leaves enormous pink funnel-shaped flowers grow
– it is former modest bindweed. And on other liana fruits similar to huge violet-brown
color pears grow right on the trunk – it is a representative of Ficus genera.
Its fruits are edible, and they have already involved one of inhabitants of
forest canopy.
Hooked claws of strange creature, hanging downwards the back, orderly clutch
at the trunk of fig liana. From time to time the tail similar on monkey’s one
clings to near branches. However any idea on an accessory of this animal to
monkeys instantly dissipates at look on its skin. From thin brownish wool striped
acute spines stick up. They are especially numerous on sides of the beast. It
is one of numerous rodents of Neocene, the sidespiny porcupine. The animal moves
on manners of the sloth, clinging for a branch by claws. But speed and dexterity
of this animal favourably distinguish it from edentate analogue.
The sidespiny porcupine has felt a smell of overripe fruits of fig liana, and
now it hurries up for breakfast. Having reached desired fruits, the animal tears
them off one by one, and brings to a mouth by paw. incisors accurately get bite
through the fruit, and the animal slowly eats it. From time to time the sidespine
licks lips by long pink tongue, not giving a precipice to any drop of sweet
juice. And losses still happen at him: clumsily having pulled for the next fruit,
he casually causes dainties to fall from the branch.
Violet "pear" drops downwards, and with rich splash falls in waters
of the small river through which the liana had reached. One second later it
slowly emerges and rocks on waves, shining on the sun with ripe side. After
some seconds the head covered with an emerald-green scaly skin emerges beside,
opens a large-toothed mouth and bites off half of fruit. Convulsively having
swallowed juicy pulp, it catches the rest and swallows it, almost not chewing.
Then the head slowly looks back and dives into water again.
The scaly owner of a green head is the huge water lizard aquaguana. Grown up
to length of 3 meters and more, it peacefully grazes by small groups on thickets
of underwater vegetation. Slowly clinging fingers for driftwood and plants,
these giants graze soft green of water plants. In the thick belly of blue color
the muscled stomach similar to chicken’s one, and the longest 6-meter long intestines
are hidden. In the stomach small pebbles pound greens to pulp from which the
maximum of nutrients is taken in intestines. Such diet allows the sluggish animal
to spend a minimum of time for food search. Having devastated one river bank,
the group of lizards swims across the river to another one, allowing vegetation
to grow up. They do not eat rhizomes, therefore the vegetation is not exhausted.
Such thin out of plants has favorably effect for an oxygen mode: the river does
not silting and water flows more freely in it. Besides aquaguanas eat floating
water vegetation which shades a river bed.
Eating, aquaguanas as if "walk" in a bottom, moving paws one by one.
If it is necessary to swim away, they are swimming, wriggling by all body and
having pressed paws to sides. And in case of danger the animal moves away by
"breast-stroke" and paddles by strong hinder legs, as if the monstrous
long-tailed frog. The large aquaguana practically does not have enemies, but
young growth is always on the alert: in the river creatures dangerous to them
are found.
From the interlacing of roots the huge two-meter fish with long arrow-like body
observes of aquaguanas. Breathing, it rhythmically opens and closes mouth in
which sharp, recurved teeth are visible. It is the pikecharacid - piranha, shark
and crocodile in one person, a sovereign predator of Amason region waters. Pikecharacids
are solitaries actively protecting the territory. But on force and ferocity
one such fish is equal to school of piranhas. This fish is the male, it is distinguished
with bright red abdominal fins.
Aquaguanas are not needed for the pikecharacid - they are too numerous and in
group they can be dangerous. Therefore the young lizard breaking off leaves
of a underwater plant in middle of group is desired, but inaccessible catch.
But here it is both more accessible and tempting catch.
Aquaguanas are true vegetarians. But their feast is not to taste to numerous
inhabitants of thickets - fishes and shrimps. Tens of these tiny creatures hide
in thickets from numerous predators, search for livelihood and breed. Shining
green and red longitudinal strips, the school of tiny small fishes swims in
thickets of underwater grasses. They are neoncichlids - small omnivorous fishes.
Some fishes differing by full mouths are males, and they carry in gular sac
eggs or larvae. Near to some pairs the big cloud of translucent tiny fries swims.
Adult fishes show them sources of food, scattering rotten leaves and ground
dust in which crustaceans, worms and infusorians - the forage for fries - are
hidden. If any shrimp swims up too close to young growth, adult fishes will
drive it off, opening operculums widely and spreading all fins. If such demonstration
will not work, the strong push by head will force to recede even the most importunate
shrimp.
But not all danger these small fishes can win even for the sake of own posterity.
When huge in comparison with fishes muzzle of the aquaguana tears off leaves
absolutely beside, neoncichlids prefer to escape. The male utters short click
and opens the mouth: it is a signal for fries to be hidden. Immediately all
numerous hatch of fries swims together to his mouth, and the fish rescues itself
and the precious burden in school of numerous neighbours. Disturbed by large
lizards, they try to hide in quieter place.
Small fishes are rescued from giant aquaguanas among roots of trees, but they
get in bigger trouble: by sharp throw the pikecharacid catches one of cichlids.
The school sharply changes moving direction, gathering to a dense sphere sparkling
by colors, and then time turns in shadow and disappears for the sight of predator.
The tiny neoncichlid is no more, than easy snack for this giant. Having swallowed
the small fish, the pikecharacid swims near aquaguanas searching for more considerable
catch. Its way lies aside a deep gulf on an opposite bank. However this place
is already occupied - other pikecharacid, the huge male of almost three-meter
length, a giant of this species lives there. And now it is especially intolerant
to neighbours: at the bottom of a gulf the deep hole in which the heap of eggs
waves is dug out. The careful parent fans eggs by fins and accurately moves
away from it rotten leaves and other dust. And fishes risking to swim in a gulf
to regale themselves with eggs, make a diet of the vigilant guard.
When the careless neighbour is visible, the careful daddy changes to real dragon.
It actively shows itself: having emerged to the surface of water, it opens abdominal
fins and trembles them, as if wings of the butterfly. Thus it utters chirring
sounds, warning the contender. The stranger male tries to not concede: it also
performs an “aria of the butterfly” and trembles by fins. Thus it turns sideways
and is stirred up. But the giant daddy is not favour to long "negotiations":
it darts off and snaps at the side of stranger. Teeth are closed at half strength,
but all the same the decent rag of skin is broken from the side of the attacked
fish. Injured large fish lefts the territory away and stands among roots of
trees.
Precaution is not superfluous - the smell of blood involves any predators, and
with some of them the pikecharacid can not cope. But now on the smell of blood
the small fish armored by osseous plates, the leechcatfish, hastens. Fins of
this fish work more as hooks, than as oars and rudders. Cautiously having stolen
up to the side of the pikecharacid, the strange fish clings to the predator
and drops a mouth similar to the sucker to fish’s wound. Quickly moving by jaws,
it scrapes the top layer of muscle rags and edges of the torn up skin. But the
fish works accurately, it does not tear healthy skin and muscles. Having cleared
the wound, the leechcatfish is unhooked and swims away. Now the wound will begin
skin over faster and will not inflame.
And the huge pikecharacid in the gulf patrols clutch, not noticing, that larceny
of precious eggs occurs directly at it near by. Sand and rotten leaves at the
river bottom are moving: under them someone small and long-bodied obviously
crawls. From time to time among rotten leaves the pinkish body of a worm-like
creature flashes. Near edge of the hole sand starts to move, and already the
heap of eggs moves soon. It is visible, as the flat head covered with flat scute,
suffices and swallows eggs one by one. When the body of the pikecharacid moves
too close above the clutch, the head is quickly hidden in sand, but later the
unpunished robbery continues again.
This fish is one more species of catfishes, the wormcatfish. It has adapted
to digging habit of life at the bottom of the river and in boggy damp ground
of rainforest. Holes of these fishes pass under roots of trees and in thickness
of wood litter, sinking to a level of subsoil waters. The wormcatfish eats tiny
animals who get in its tunnels. Due to keen sense of smell this fish easily
finds motionless food - carrion or fish eggs. It quickly digs under interesting
object a burrow from below, and thus it remains unnoticed, and frequently unpunished.
On sides of this catfish the line of small osseous plates is located. They are
mobile and help fish to creep in holes. As a shovel and a drill the plate on
the head and strong forward somactids of the reduced pectoral fins are used.
Wormcatfishes are digging in wood litter on a coast of the river. Sometimes
from a layer of fallen leaves the flat head of the fish is put out, and catches
snail or beetle. Strong jaws of the fish split their shells with hardly audible
crunch. But catfishes are constantly on the alert. They are frightened with
any strong concussion of ground. And they appreciablly are nervous, moving by
heads asides: fishes are almost blind, but clearly feel someone's steps. And
they hasty come back in the dark underground world.
On a wood litter in direction of the river the sidespine goes by clumsy steps.
The animal constantly is stirred up and looks small eyes around. He was tortured
by parasites, and the animal wants to exterminate them. All prickly animals
face with this problem: fine protection against a strong predator at all does
not rescue from tiny bloodsuckers. Hedgehogs of Holocene time pinned sour apples
on spines and poison parasites with their juice, and the sidespine of Neocene
is rescued from parasites by more simple way: he bathes.
The sidespine is good swimmer. He is not afraid of water and willingly has a
baths. The animal comes into water up to the neck and starts to be stirred up.
Wool is left with bladders of air and water impregnates wool of the beast. Having
stood in water a little, the sidespine lies down, having put out from water
only a tip of a muzzle and eyes. His needles become covered by set of parasites
looking for rescue. Here fleas, ticks and even larvae of small beetles are.
All of them caused inconvenience to the beast by their tireless activity, but
payment for carefree life had came now.
Translucent shrimps cautiously swim up to the sidespine stood at a coast and
start to pick free fare. From time to time the animal is stirred up to wet wool
better, and river inhabitants get new portions of parasites.
Shrimps can feel like in safety: large fishes do not touch them near the sidespine,
but the sidespine does not suspect, that it is in big danger. His movements
have drawn attention of the pikecharacid. The two-meter giant having skin torn
off on one side slowly starts to creep to the prickly animal. It yet had not
seen such animal, and accepts it for easy catch. Carefully having aimed, the
killer fish attacks it by prompt throw... and the same moment jumps aside. In
a mouth of the pikecharacid some striped spines are stucks up, and the sidespine
thrown off to considerable distance from a coast, hurries up on land. The splash
of water under his paws provokes the pikecharacid to attack again, but at this
time the animal is ready to defense. The sidespine dives under the head of the
pikecharacid and beats it by claws. Then by fast movement the animal emerges
and reaches a coast. Coming out on a coast, the sidespine is stirred up and
smells air long time then approaches to one of trees and slowly comes back to
his native world - to height of tens meters from the ground and water.
The pikecharacid, having received one more wound, leaves under roots of trees.
It’ll not remain hungry: the wood gives to a predator plenty of food. Frog,
fish, beetle fallen in water - all this ones are quite edible. Sometimes from
a tree catch of other sort falls: clapping half grown wings, from a tree the
nestling of any bird falls. It can not fly yet, and wings only slow down a little
its falling. The splash of water signals the pikecharacid that the table is
set. The prompt throw is made - and nestling disappears in the mouth of the
large fish.
Flying by above water, adult birds also can become prey of the pikecharacid.
The flight of bright birds, frequently flapping wings, flies above quiet water.
But suddenly from water the silvery alive arrow jumps off - and one of birds
does not reach the saving coast, seized by ruthless jaws.
Aquaguanas, as against the pikecharacid, are harmless, despite of frightening
shape. They keep congestions including to secure itself against the killer fish.
But they spend in water not all time - having sated, lizards crawl out on sandy
spits and banks and have a rest basking at the sun. Warmth is necessary for
them for digestion because of it the enzymes secreting with their intestines
become more active.
Striped giants behave on a coast, as if first-rate health-resort visitors: they
luxuriate laying on stomach or on one side, having spread paws wide. From time
to time one of lizards creeps on other place when a shadow from liana or branches
closes the sun light to it. Lizards so relax and leave in themselves, that butterflies
without fear sit on their heads and their proboscises exhaust liquid which is
flowing down from tails of eyes and nostrils of reptiles. It is important for
them as gives to insects necessary mineral substances. When the annoying butterfly
sits on a head of aquaguana and thrusts a proboscis in tail of an eye of the
reptile, the lizard only blinks an eye in answer. When the butterfly bothers
the lizard finally, reptile stirs up a head and banishes an insect.
But one of river inhabitants cannot afford to itself so idle life: warm blood
demands a lot of food. From the hole in river precipice the short wide muzzle
covered with wool appears. It yawns, showing two pairs of lemon-yellow incisors
which bottom pair is especially long. After a head from the hole long body on
short webbed paws is shown. This creature also is finished by flat wide hairless
rosy-brown tail. This animal similar to the otter is the otterodent, the rodent
had adapted for water habit of life and a feed by fishes. The animal sniffs
at river bank, and then comes into water and dives. Under water it moves excellently:
bending body in vertical plane and helping itself webbed hinder legs, the otterodent
develops the big speed. Third eyelid of animal is transparent, under water it
works, as underwater glasses, allowing to see good.
The otterodent gets out on small island where aquaguanas luxuriate. Its occurrence
causes alarm in lizards: some of them have on the body wounds and scars - traces
of otterodent attacks. Aquaguanas accept the fighting rack: having turned to
a predator back and looking through a shoulder, they start to swing long tails
and threateningly to hiss, inflating a red gular sac. The otterodent well knows,
how impact of such tail is dangerous: at it(her) under wool on a shoulder the
long scar received in youth is latent. Therefore the young fat aquaguana sitting
among adult giants, for it(her) completely inaccessible catch.
The otterodent keeps aside of hissing aquaguanas: it bypasses them, slapping
by paws on water surface. Completely reasonably it keeps itself from an attack
on reptiles and dives again.
In water the otterodent starts to survey thickets of water plants. By experience
the animal knows, that a lot of catch is hidden there. And diligence of the
woolly fisher is made up: from thickets the young half meter long pikecharacid
swims out. The otterodent knows: this fish does not like to swim far, therefore
the animal starts to drive the pikecharacid, continuously pursuing it. Some
minutes - and by exact impact the otterodent kills dangerous fish. Long incisors
of the bottom jaw pierce in a backbone of the pikecharacid from the side, and
the top incisors almost bite off a head of fish.
Having griped killed fish in teeth, otterodent leaves on river bank. Here it
sits on hinder legs and starts to bite off pieces of the pikecharacid body,
holding it by both forepaws. Soon from catch only fins and a large-toothed bony
head remain. Having thrown leavings in shallow water, the otterodent comes out.
And a head of a creature, which about hour ago was a fear of small inhabitants
of this bank, now involves numerous translucent shrimps and fries.
The otterodent does not pay attention to the smallness which had surrounded
rests of its catch - it is sated. The animal reaches huge driftwood and gets
out on it. Having stirred up, the animal lies down and has a rest, having lowered
paws to water. The otterodent has nobody to be afraid, except for the adult
pikecharacid. But also the pikecharacid not always risks to be seized with the
otterodent: winning in size, it loses in a maneuverability and endurance. Therefore
both predators try as it is possible to meet each other’s eye less often, and
the woolly fisher quietly can fall asleep under hot beams of the tropical sun.
Here there are rains each day. But many kilometers far from these places, at
the north, the rain turns to joyful event from daily routine, and its absence
is usual way of life. In deserts of Northern America struggle for water and
struggle for life are almost same things.
Bestiary |
Leechcatfish (Hirudistomus cataphractus)
Order: Catfishes (Siluriformes)
Family: Loricariidae
Original fish, representative of the family of armored catfishes
(Loricariidae). Similarly to the majority of representatives of this extremely
diverse family, the fish has mouth modified to scrapping sucker. The majority
of its relatives eat microscopic algae, scrapping them from stones and driftwood
by such mouth, but the leechcatfish has other gastronomic predilections. This
fish prefers carrion, eats meat away from wide wounds of fishes. Sometimes African
catfishes Synodontis from family Mochocidae adhere the same diets. But a feed
by a carrion is unsafe - bacteria and cadaveric poison can be an absolute obstacle
for species starting adaptation to feed by carrion. However at this catfish
the fine mechanism of protection was developed: for protection against cadaveric
poisins in a mouth of a fish there are glands, producing enzymes and antibiotics.
This adaptation has given it one more benefit: attacking on fishes with open
wounds on a body, the catfish is more advantageous, than damaging to it, clearing
wounds on a body of these fishes. Natural selection has transformed this fish
from a predator to the original doctor.
The leechcatfish is the medium-sized fish: the body is about 20 cm long, very
thin and long, tail mounts the significant part of length. Pectoral and abdominal
fins of a fish are extended, and their forward somactids had changed to dense
"brushes" formed from tiny spines. Coloring of the fish is dim: grey
background with black strip on back, belly is white. Males have red spot on
a back fin. The fish differs by original care of posterity: the male bears spawned
eggs on belly.
Wormcatfish (Caecodoras vermiformis)
Order: Catfishes (Siluriformes)
Family: Doradidae
This is high-specialized species of armored catfishes family (Doradidae). The
fish had descended from bottom-dwelling catfishes and has gradually adapted
to life in a thickness of silt and ground. Body is scaleless, pinkish-colored,
up to 30 cm long, width is up to 3 cm. Skin on belly is thin, through it some
interiors of the fish are perfectly visible. On a head there is the shell plate,
assisting to dig ground: it is the rest of shell covering at modern catfishes
of this family all front part of the body. Lateral shell plates had remained
and had changed a little - they help to creep in a hole. Due to strong muscles
in the basis they can rise and fall, allowing the fish to push off from walls
of a hole or to be fixed in them. Almost all fins are reduced, there was only
tail fin which somactids were split lengthways and had formed the original "bottlebrush"
allowing a fish to push off from walls of a hole. Pectoral fins had almost disappeared
- from them there were only very powerful forward somactids, using as the instrument
to loosen ground and the device for capture of food - worms and larvae of insects.
Eyes of a fish are reduced – they differ only light and darkness. Gills are
very small, latent under the valves of skin interfering their chocking up. At
a catfish lung and skin types of breath are advanced.
This species can live in water and in damp ground. The catfish digs long tunnels
through the wood ground on a water level, therefore in its holes it is always
damp also its skin does not dry up.
It is live-bearing species, the female bears from 5 up to 12 fries. First time
young fishes live in a layer of silt of small streams with dark water, starting
to dig tunnels later.
Dwarf neoncichlid (Nanocichla pusilla)
Order: Percoid fishes (Perciformes)
Family: Cichlidae
Cichlid family (Cichlidae) is one of the most diversified and
richly presented families of fishes in Amason region. It includes such known
to aquarium-keepers genera of fishes, as Aequidens, Cichlasoma, Astronotus,
Pterophyllum, Geophagus and many others. Cichlids of South America are mainly
medium-sized and large fishes. But in the future when large species easily can
become extinct because of ecological crisis, the role of river giants can easily
pass to characids (Characiformes), another large group of American fishes. They
will transfer such extinction with rather small damage, we can see plenty of
their species today – from tiny and small fishes to some species grew to length
of 1 - 1,5 meters. Therefore it is possible, that more numerous characids will
occupy ecological niches of cichlids and left to cichlids “extra” roles in ecosystems
this way. But the main feature of cichlid behaviour, their care of posterity,
will help some survived species of them to compete freely to characids simply
spawning in suitable places and sometimes having eaten their own eggs. Therefore
in the future it is probable, that these two groups of fishes will exchange
leading roles in ecosystems.
The dwarf neoncichlid is one of tiny species of Neocaenic South American cichlids.
The length of this fish is about 5 cm, the male is almost 1,5 times larger than
the female. Bright neon strips on sides (from above along a lateral line there
is green strip, from middle of a body up to a tail fin – red one is) help small
fishes to distinguish neighbours and to distract a predator. At males the back
is black and a vertical black strip passes through an eye, at females - back
is grey, and green lines on sides are wider, than at males. Back fin of the
male is higher, than at the female. The neoncichlid is the schooling small fish
forming congestions up to 100 ones. The constant leader of school is not present,
the school consists of set of breeding pairs, single sexual matured fishes and
fries. The male incubates eggs in the mouth, fries of younger age are hidden
in the same place at the case of danger. In hatch there is up to 30 - 50 fries,
but up to independence only about half of hatch survives. About 2 weeks the
young growth is protected by parents, later fishes start to live independently.
Fries form separate one-age schools.
Fish eats small invertebrates.
Pikecharacid (Deinocharax esocignathus)
Order: Characids (Characiformes)
Family: Lebiasinidae
Characid fishes (Characiformes) are one of the most successful groups of Amazon
fishes in evolutionary relation. Among them there are predators as Serrassalmus,
Hydrolycus, Chalceus (in Africa their list Hydrocinus supplements), and exclusively
herbivorous fishes Colossoma, Methynnis, Leporinus (in Africa – Distichodus).
The majority of characids species includes omnivorous fishes biased in vegetarianism
or predating. The majority of characids has the small or tiny size that raises
probability of their survival in conditions of reduction of efficiency of biotopes.
And ecological plasticity of some characids allows to suppose, that after mass
extinction of species the big future expects this group.
The pikecharacid is huge (2 - 2,5 m long) carnivorous characid had replaced
in the river predators of Amason region piranhas and crocodiles which had became
extinct at the end of Holocene. Such species can not meet by big schools – this
fish is extremely territorial, protecting its living area. A body of the fish
is arrow-like, back and anal fins are arranged far back. Head is big, flat;
the mouth is wide, its edge proceeds up to a vertical of back edge of an eye.
Teeth are slightly recurved, numerous, sharp, needle-like. They help to keep
the caught slippery catch - fishes and frogs. Body of the fish is silvery colored
with a blue shade, back is darker. Abdominal fins are wide with black forward
somactids and red spots, and at males they are much longer, than at females.
The fish is top-skimmer, and these bright fins are well seen from below: they
are used at submission of signals and demonstration of threat. The fish opens
them and pulls short sharp movements, accompanying clicking sounds with this
demonstration. Eyes are large, yellow-colored. Tips of jaws are black.
This species is the descendant of the trout copein (Copeina guttata), small
species of Amazon fishes. From it the pikecharacid has inherited a way of posterity
care: eggs are spawned in a small hole at the bottom of the river, and the male
protects clutch - up to 20 thousands of large eggs, swollen in water. In 2 weeks
large fries hatch from these eggs, and the male abandons them. Fries grow quickly,
eating any catch from which they can cope. In 3 years the fish already becomes
sexual matured, having grown to length near 75 cm. It lives till 30 years.
Aquaguana (Aquaguana herbivora)
Order: Squamates (Squamata)
Family: Iguanids (Iguanidae)
Picture by Pavel Volkov, colorization by Alexey Tatarinov
Initial picture by Pavel Volkov |
Amazon river of the future will lose many herbivorous inhabitants:
large piranhas Colossoma and Myleus eating plants will disappear, and also aquatic
mammals manatees already in historical time appeared endangered species. These
animals had disappeared because of cold climate in late Holocene epoch. And
ecological accident of a boundary of Holocene and Neocene has finished the history
of their existence. But herbivores water animals nevertheless have remained
in South-American region: they are iguana lizards. They had survived in the
rests of bank woods of an Amason region during the ice age, and later had adapted
to eat water plants instead of wood vegetation. The iguana swims well, and this
ability had very much helped it at development of a new ecological niche.
The aquaguana is the large iguana eating water plants instead of manatees. It
keeps by groups on 10 - 20 animals, as rate of eating and growing of plants
lizards move upwards and downstream the rivers. The length of the body is 3
- 4 meters, tail accounts half of length. Color of skin is bright-green with
thick irregular vertical strips. Such coloring makes the reptile undistinguished
in thickets of water vegetation. Belly of the lizard is blue, on a throat there
is a folding red-colored gular sac with a cartilage basis attached to jaw bones.
When the animal threatens a predator or the contender, the cartilage is spread
out also a gular sac becomes good visible. Males are larger, but more thin than
females, on a head of the male needle "crest" grows, especially appreciable
at old animals. Coloring of the male is brighter, than at the female, and the
gular sac is larger. Jaws of the reptile are strong, there are small fleshy
cheeks; teeth are leaf-looking with sharp cutting edges, they are closed scissors-likely.
The water habit of life has changed shape of the reptile - membranes between
fingers had appeared, back legs became stronger. On tail high skin plica using
as tail fin had appeared. A usual way of swimming of the reptile is bending
by all body, high-speed habit of swimming is the "breast-stroke" similar
to frog kind of swimming. At an attack of the predator in water the reptile
tries to swim out and climb out on land where lizard has advantage in might:
it protects itself in in-fighting by strong tail impacts. The seized aquaguana
bites and scratched by strong claws.
The aquaguana lays eggs (up to 40 ones in size with goose egg) in wood litter
and does not protect place of nesting. Young lizards emerge after 2 months of
incubation, length of the newborn aquaguana is about 20 cm. In 5 years the lizard
becomes adult.
At the Caribbean Islands one species of land iguana Cyclura had evolved to dominating predator in ecosystem.
Otterodent (Pseudolutra praedonis)
Order: Rodents (Rodentia)
Family: Neoichthyomyidae
In historical time in Brazil large fish-eating mammal - the
huge otter (Pteronura brasiliensis) lived: its length was up to 2 m and more
including tail. At approach of ecological cataclysms and extinction of a plenty
of water animals this species had become extinct. Besides its number was undermined
by unlimited hunting of people. Standing empty ecological niche was occupied
with uniquitous rodents, and the ancestral species with all inclinations for
this changing was the contemporary of otters.
The otterodent is the rodent, the descendant of small South-American aquatic
rats Ichthyomys. This animal had considerably increased in size in comparison
with ancestors: the otterodent is up to 1,5 m in length. Hairless tail (it makes
1/3 length of a body) is flat and serves for swimming - the animal moves, bending
backbone in vertical plane. Hinder legs are oar-like, with long fingers and
advanced swimming membranes; forepaws have well advanced fingers, with their
help the animal holds large catch. wool is dark brown, water-proof, greased
with fat from special glands in axillary area. At an adult animal a chest and
throat are white. Head is flat, front department of skull and jaws are short,
jaw muscles are very strong. Incisors have lemon-yellow coloring of enamel.
Bottom incisors are very long, jaws are capable to be opened very widely. It
is connected to a way of killing of large catch: the otterodent sticks bottom
incisors in a backbone of prey, and then puts bite by top incisors, gnawing
through the backbone of catch.
Otterodent feeds by fishes and water animals catching in thickness of water,
pursuing it actively. Molluscs and crustaceans are digging by animal out of
sand by sharp-clawed forepaws.
This is the solitary animal, only female and her cubs live together any time.
Adult animals keep together only during time necessary for pairing, for some
hours. This time the male can look after the female, feeding her with fish.
Pregnancy lasts about 4 months, there are 3 - 5 cubs in pack. Females with cubs
can be met at any time of year, but it is more often at the end of rain season
when rivers are especially rich in fishes. Lair is wide hole in river bank,
at the female with cubs the hole is deeper, than at the male, but the entrance
is smaller, that preserves cubs against the males inclined to cannibalism.
Sidespiny porcupine, the sidespine (Bradycoendou laterispinus)
Order: Rodents (Rodentia)
Family: Erethizontidae
Picture by Amplion
When rainforests of Amason region had practically disappeared,
the huge amount of alive creatures, inhabited their, had became extinct. When
the Earth had recovered after change of epoch, the damp climate had caused new
rainforests to life. And the Neocene fauna which has occupied them, represents
a mix of relic Holocene rainforest inhabitants and descendants of animals of
leaf-falling and evergreen dry woods adjoining to pampas. Some species had the
big successes in development of new habitats. The sidespiny porcupine, the large
climbing rodent is also among them.
Specialization to climbing at these species is high-grade: the animal suspends
itself on trees with the help of hooked bent claws similar to wood sloths of
Holocene and some Madagascar lemurs of Pleistocene. The animal looks like sloth,
but as against it has the prehensile tail assisting at tree-climbing. Besides
the sidespiny porcupine moves on trees much faster, than the sloth. Paws of
animal are very long and muscled, the neck is too lengthened, allows an animal
to eat leaves, hanging on a branch from below. Mobility of cervical vertebrae
is very great: the head of the porcupine can make almost full turn around. Jaws
are short, incisors have orange enamel. The porcupine eats leaves and fruits
of plants, sometimes ravages bird nests and eats frogs. As against sloth, the
porcupine can move on the ground on slipped feet, thus claws of an animal are
directed by ends under the body, and the support falls to external edge of foot
and hand. The animal swims not so bad and frequently goes down to water to exterminate
parasites difficult for combing them out from wool.
Wool is brown, rather thin, spines are striped, brown and white. Most of all
spines are grown on sides of the animal, in middle of a back along a backbone
there is a strip of the wool, almost devoid of spines. The stomach of an animal
is devoid of spines completely.
The porcupine lives in forest canopy at height of 20 - 30 meters above the ground,
preferring areas of wood near to water. It keeps by groups of 3 - 4 animals,
adult males frequently live alone. The breeding season begins in the middle
of a dry season, only cub is born to a damp season when there is abundance of
food. The cub is born very much advanced, with opened eyes. In one week after
birth it already tries food of adults, and in 2 months manages without parent
milk. In 5 months it is completely independent, though keeps near to mother
up to the age of one year.
Some endemic species had descended from wood porcupines at the Caribbean Islands.