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Tour to Neocene
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THE INCREDIBLE WORLD TOUR TO
NEOCENE.
LIFE ON THE EARTH 25 MILLION YEARS IN THE FUTURE
The history of creation of this book had begun a long time
ago – I still had attended school at that time. In one issue of “Around the
world” magazine (nr. 10/1988) I had seen for the first time the article about
researches of the English scientist and paleontologist Dougal Dixon concerning
the evolution of live beings in the future, after the human era. This short
article added with few illustrations, probably, was deposited in my subconsciousness,
as if the Archaeopteryx in marsh silt which in the future had become well-known
Zollenhoffen slates. And this “Archaeopteryx-in-consciousness” had waited for
the hour of triumph for many long years.
Later, already having entered the institute, I have read with interest Harry
Harrison's fantastic trilogy “West of Eden” where the Earth, on which the asteroid
has not impact at the end of the Cretaceous period, is described. In addition
this book has set me thinking about problems of life evolution on the Earth
and about possible directions of this process. And absolutely completely the
idea to create this book took shape at me when in 2002 science-fiction film
“The future is wild” had been shown on screens of the world. And then I “was
gone” with this idea finally, having burned with the idea to look in the future
of the Earth.
This film has caused at me plenty of various questions: because of it I call
it not “scientific-popular”, but “fantastic” at least by 5/6 - 10 series from
12 ones had caused those questions at me. At least, ten venerable doctors of
Philosophy and academicians from the most prestigious universities will never
convince me that some of the animals presented in film (it is more exact to
name this amount by word "many") can appear on the planet.
Besides, the chronology of the film abounds in giant time blanks: in fours series
of film have devoted to the life on the Earth at 5, 100 and 200 million years
in the future. And what was between them? What was ways of involuntary researches
of the live beings, directed to their survival? What creatures will inhabit
the world in those places and at that time about which it was not told in film?
And then the plan of this book was occurred. I have decided not “to skip” in
time, surprising those persons, which will read my words, with my ingenious
insight (partly owing of its absence): the careful reader necessarily will be
founded, who will sit for books and completely arguably will deny my theses.
Especially it concerns just the sight in the far future. I repent, having seen
the film “The Future is Wild” and having read the book according which it was
created, I had made the same thing. That is why beforehand I want to tell, that
I keep my mind opened not only for the praise (if it will be), but also for
shattering, ruthless and destroying criticism (and it is not to be doubted in
its reality). And nevertheless, I have dared to sit down at computer (completely
unexpectedly for myself having seen on the keyboard familiar letters) and to
start to embody the ideas in typed words. In the beginning I did not know precisely,
how many chapters will be in final variant of this book. You see, it always
happens by this way: gradually you enter into working passion and you see, that
it is possible to make one more step beyond the horizon, and then one more,
and more, more... And it turned out as many chapters in this book, as many are
them now.
In work at this book I had partly used some ideas and facts of possible changes
of the planet, submitted in film and the book “The Future is Wild”, at least
that part of them, which did not contradict common sense. Therefore I make this
work as the addition to this project, but I do not know, will it be logical
and pertinent, or not. But let scientists and readers (that is the most important)
judge it.
I have decided to limit my fantasy only with one “jump in time” and to show
the vision of the world, what it can become after 25 million years in the future.
But I have decided to arrange chapters of the book so, that they will made a
route of whole travel - around of whole planet, from the pole up to the pole,
across all continents and oceans, in all natural zones, at all seasons. But
before this improbable travel I want to make the small stop in present time,
because without it everything, about what I shall tell further, will be idle
talk.
Slightly opening the veil of time…
How to predict the future? |
In general, the predicting is the most ungrateful thing in
the world, because the reality obstinately denies the most courageous predictions,
bringing to nothing the work of numerous mediums, cartomancers and simply big
optimists (or pessimists). Certainly, it is good, when the worse forecasts do
not come true. But more often it happens absolutely on the contrary... Judge
it. One ancient Greek mechanics, the inventor of ballista, had declared, that
he had created the “superweapon”, and because of it he predicted, that wars
on the Earth should stop completely. Later (after numerous wars of an antiquity,
Middle Ages and New Time) when the plane was invented, military experts have
again predicted the termination of wars as positions of the conflicting parties
are perfectly visible from the plane. Later, after the invention of bombers
and destruction during two world wars of numerous cities practically up to zero,
the nuclear bomb was invented (I shall notice, that it had been dumped from
the plane which invention as if completely should stop wars). Then people again
began to hope, that wars at last will be stopped. While nobody, except for Americans
(in 1945 in Japan, if anyone has forgot it), has not used the nuclear weapon
in war. But the “hotheads”, ready to make it, are very numerous and, unfortunately,
are “hot”.
This example from a human history shows, as far forecasts and reality miss sometimes.
It is necessary to pay attention, that all forecasts, listed above, were made
in rather small interval of time - some thousand years in total. And what can
we speak about larger intervals of time? Thousand years for the natural history
of the Earth is like life of the infusorian in comparison with the life of tortoise
or the crocodile. If the accuracy of “short-term forecasts”, concerning the
destiny of only one biological species from millions, is so insignificant, how
is it possible to predict the future of the whole biosphere?
It appears, that it is possible to do it up to a certain extent. Accuracy of
this prediction, certainly, leaves much to be desired, but it is possible to
try to make it. The point is that the key to the future the past and the present
time can give us. People, studying various rests of fossil organisms, have deduced
the set of laws, stable shown in history of various groups of live beings. Applying
it to modern species, it is possible to find out approximately, who among modern
species has the big future, and who is the first candidate for extinction.
Now I also want to talk about these laws.
Thorny road of evolution |
Can evolution be the casual process?
Evolution did not proceed at all like any casual process as
very ignorant (or on the contrary, perfectly informed, false and artful) supporters
of the creationism (the theory asserting, that all world was created by will
and power of the certain deity) would like to introduce to the uninformed reader.
As the "argument" they result the numbers showing huge amount of variations
which can arise at casual process of "self-assembly"
of initial molecules of the DNA... not bacteria, not amoebas, and at once the
human being! Thus they diligently write down at the illustrations in their booklets
by small font some lines of zeros to frighten the reader not trusting them,
to show to him “evidently” the impossibility of “casual occurrence” of alive
creatures, and after it to bring accurately the uninformed person to diligently
advancing in his brain idea about the intervention in life development of certain
intangible, but very much general force usually representing as the kind old
man in white clothes with broad beard and luminous ringlet above the head. But
the human was not formed “from zero” - it is the result of long process of evolution!
It is the result of development of already had appeared structures! Just as
at construction of any building brick is not inventing anew, and already available
one is using.
The approach based on understanding of evolution as of the sorting of “casual”
combinations of genes, is radically incorrect. Some of gene combinations simply
can not appear initially - even “first step” to some directions of evolution
will be cut by natural selection in any case and in any conditions. Otherwise
it would be possible to expect occurrence during this hypothetical “casual evolution”
of such “monsters”, as the crow covered with wool, snail with dragonfly wings,
or mole with eagle eyes. However they are not present in nature, though they
just correspond to that deformed doctrine, which creationists pass for the “theory
of evolution” - they are the product of the required “casual combination of
genes”. Having invented the next “scary story”, supporters of the theory of
divine creation, figuratively expressing, solemnly jump in grave dug for supporters
of the theory of evolution. They “deny” not the theory, but their own
deformed representation about it, rather far from true one.
Laws of evolution
Studying development in time of various groups of live beings, scientists have
deduced some laws about which I want to tell now. I think, there are no bases
to assert, that these laws are correct only for prehistoric life and will not
be valid in the future. Certainly, in present time the active creative-destructive
activity of the human brings the corrective amendments in processes of evolution,
but in the future if the people will come to disappear (this event will take
place sooner or later according the natural or artificial, created by people,
reasons), laws of evolution in all their magnificence will drive the development
of the wildlife.
So, what about these laws? It is not so big number of them, and they concern
different features of live creatures in terrestrial conditions. Some of them
determine the common principles of evolution, other ones concern destiny of
separate evolutionary line of alive creatures, third ones - evolution of separate
organs and their systems. All of them are perfectly shown at various groups
of alive creatures, and I simply shall try to illustrate each law with the striking
and graphic examples.
I have stated formulations of laws according Nikolay Fyodorovich Rejmers's book
“Ecology (theories, laws, rules, principles and hypotheses)”. But those laws
directly concerning evolutionary process, about which I want to tell, are only
a little part of science, that is necessary to take into account at the “reconstruction
of the future”.
The L. A. Dollo’s law of irreversibility of evolution: the organism (population, species) can not return to the former condition which has been already realized in the number of its ancestors. |
The example of display of this law in the nature is simple:
cetaceans (Cetacea), sirens (Sirena) and pinnipeds (Pinnipedia) are sea groups
mammal. They have to the greater or lesser extent mastered the water environment,
but in the life they are continuously connected with the air environment. They
already never can get the gills lost by distant ancestors of ground tetrapods,
therefore their adaptation to the water environment will not be such full, as
at fishes.
One more example is the change of teeth at mammals. At reptiles and fishes (for
example, at sharks) teeth are changing repeatedly during all their life, at
mammals (including us, people) it takes place only twice: deciduous (milk) and
permanent teeth. Some paleontologists connect it with the fact that first mammals
have lived not for long time and simply did not live up to the third change
of teeth. If it would been predetermined (certain, perhaps, by “the Supreme
Forces”), that mammal will become dominant group of large animals of the Earth,
and some of them will live up to 80 - 100 years, our tiny shaggy ancestors would
hardly leave an opportunity of repeating change of teeth. But it nevertheless
has taken place. Therefore modern mammals have developed instead of simple change
of the worn out teeth new original mechanisms of replacement and updating of
the teeth, absent at other large-toothed vertebrates. At elephants and the kangaroo,
for example, permanent teeth appear as if the “conveyor” from depth of mouth
forward, and at the horse molars increase from below during all life. At the
same time at the dinosaur or the shark the worn out tooth for few days is replaced
by new one. And at mammal change of teeth more than two times is rather seldom
meeting phenomenon, than the common rule.
The K. F. Rouillier’s law of complication
of the system organization: historical development of live organisms (and
also of other natural and social systems) results in complication of their
organization by the way of increasing of differentiation of functions
and organs (subsystems) which carry out these functions. |
Any part of animal or plants body during the evolution process
tends to complication. It is possible to see, for example, as the fin of primitive
sarcopterygian fish, turning to an extremity of the tetrapod animal, is losing
the characteristic structure looking like “herring bone” of repeating elements.
Such fin was kept, for example, at the Australian barramunda (Neoceratodus).
Features of this “herring bone” still can be seen in the anatomy of fin of the
most advanced crossopterygian fishes. And in the extremity of amphibians and
others tetrapods already residual elements of the “herring bone” fin are guessed
hardly. But bones and their connections had lost the ancestral uniformity, getting
specialization and ability to more various movements. Look even at the thumb
of human hand: how much various movements it can do!
Segmented body of annelid worms consists of set of rather uniform segments:
in each of them there is a part of digestive, nervous, secretory and partly
sexual systems of organs. At the each segment there are organs of movement -
the parapodiums similar to rudiments of legs. The body of insects and arachnids
has inherited segmented structure from ancestors - annelid worms. But segments
of their body are qualitatively different: legs are present not at all segments,
for example, in one segment the element of secretory or sexual system is more
advanced, and the nervous system in this segment is presented only by pair of
tiny nerve ganglions. But in the next segment elements of secretory or sexual
system can not be presented at all, but there is the pair legs and wings (at
insects), and the nervous system is presented by large complex nerve ganglion.
And in ecosystems this law is showing completely, certainly, fossils are incomplete
and can not allow to assert something at 100 %. And nevertheless it is established,
that on reeves of Caembrian period at the area of some square kilometers about
50 species of animals had lived simultaneously, in middle of Paleozoic - up
to 400 ones, in Mesozoic - over 1 thousand species, and in Cenozoic - more than
5 thousand species! Certainly, it is necessary to make some amendments to the
safety of fossil organisms, but all the same the tendency is appreciable.
The law of limitlessness of progress: development
from simple to complex stage is evolutionary limitless. |
Evolution on the Earth was not finished at the present time
with occurrence of the human (as “progressive” supporters of the theory of the
divine creation assert, admitting the change of live organisms in time); it
is proceeding right now. Now plenty of “not finally generated” species of alive
creatures are known. Such species at edges of living areas behave as “normal”,
completely generated species, but at the overlapping areas they form fertile
hybrids or certain bridging form. Or on the contrary, in places of common inhabiting
such species do not form hybrids, or the posterity of them is sterile, but individuals
from not overlapped habitats are freely hybridizing also their posterity is
limitlessly fertile. It happens sometimes, that one species gradually “pass”
to another ones, and to determine borders between areas is practically impossible.
Or the species is precisely divided to the number of semi-species, distinguishing
a little from each other by the morphology, but precisely differing genetically.
In due course, the occurrence of twin species, indiscernible externally, but
differing genetically and by features of behavior, is also possible. Such species
are known now at mosquitoes, some fishes and frogs.
For set of species of live creatures existence of the human has became simply
one more factor to which they adapt (or, on the contrary, can not adapt and
die out). Thus some species living together with the people, evolve extremely
quickly. The rats are those, evolving for hundreds of years to numerous local
forms on islands where they have arrived due to the people. And in Northern
America the local fruit fly, the apple-tree fly (Rhagoletis pomponella) has
adapted to an inhabiting at the apple-tree, introduced in America. The first
cases of apple tree infection by this insect mentioned in 1866. The apple-tree
fly is American species by the origin. Before the introduction of the apple-tree
to America it lived at the local species of hawthorn. Now the races of these
species living at the apple-tree and the hawthorn, are not hybridizing even
if the apple-tree and the hawthorn on which there are representatives of these
species, are growing beside.
To look after formation of new species for one generation (and even for hundred
and one) of human life in natural conditions is impossible, but it is possible
to reveal occurrence of stabile deviations from the initial form at the population
which have got in new conditions, in some decades with the help of methods of
mathematical statistics. And in laboratory conditions action of any forms of
natural selection is perfectly modeling and perfectly shown evidently, that
shows, that species are subject of action of selection (and evolution) today.
Inside the genotype of organisms there are no any special “terminators of development”,
stopping development of species of live beings at the any time or in the certain
conditions. Amount of genes and their combinations at organisms is practically
indefinite (even supporters of the theory of divine creation admit it) though
by virtue of differing in directions of evolution of separate groups of alive
creatures some combinations of attributes are impossible.
Unique two restrictions for evolution of live creatures of terrestrial type
of organization result not from internal, and from external factors: these are
conditions, suitable for existence of the protein life on the Earth and time
of existence of the Earth as the planet.
Rule of acceleration of evolution: with increasing of complexity of the biosystem organization duration of species existence is reduced on the average, and rates of evolution are increasing. |
If we shall arrange chronologically the basic stages of development of life on the Earth, the interesting picture will be turned out:
Origin of life | 3.8 billion years ago (or earlier) |
Occurrence of photosynthesis at procaryots (organisms without nucleus in cells) | 3.7-3.5 billion years ago |
Occurrence of eucaryotic organisms (organisms in which cells there is the nucleus) | 1.9-1.6 billion years ago |
Development of colonial organisms | 1.6-1.3 billion years ago |
Division of organisms to kingdoms (animals and plants) | 1.0-0.9 billion years ago |
Mass development of multicellular organisms (so called “Cambrian explosion”) | 600-550 million years ago |
Expansion of life to land About | 430 million years ago |
Expansion of vertebrates to land | About 370 million years ago |
Occurrence of amnyotic organisms (organisms having germinal environments) | About 340 million years ago |
Occurrence of mammals | About 250 million years ago |
Occurrence of primates | About 70 million years ago |
Occurrence of monkeys | About 35 million years ago |
Occurrence of apes | About 20-22 million years ago |
Occurrence of the human (genus Homo) | About 1.5-2 million years ago |
It is necessary to pay attention to the fact, that the evolution
eventually is accelerated in time. So, for the formation of nucleus in cell
of unicellular organism the first half of time of existence of life had spent,
and the majority of other important events (including occurrence of multicellular
organisms and formation of intelligence) had occurred at the last half of this
time.
In this connection it is necessary to recollect the phenomenon of species named
by Charles Darwin as “alive fossils”. They are the species of live creatures
kept up to present time practically unchanged. Among such species, there are
trees Ginkgo and Degeneria, tadpole shrimp Triops,
mollusc Nautilus, marsupial mammal opossum Didelphis, as an
example. It seems, the evolution does not rule above these species... But it
just seems. Among “alive fossils” there are no progressive forms; all of them
are rather primitive. And rate of evolution of primitive forms is slower, than
at progressive ones. At presence of suitable habitat and slow rates of its change
(not exceeding rate of evolution of “alive fossil”) such species can exist unlimitedly
long time.
Soviet evolutionist Ivan Ivanovich Shmalghauzen has revealed the appropriateness
between position of the species in feeding chain and speed of its evolution.
So, he has divided the feeding chain to 4 levels:
1. Organisms protecting against predators only by high breeding rate. Such strategy is characteristic for bacteria, unicellular organisms and some multicellular forms forming plankton.
2. Organisms having passive protection against predators (shells, crusts, spikes) – they are molluscs, crustaceans, higher plants.
3. Organisms capable to protect against predators due to speed of moving.
4. Predators occupying the top of feeding chain.
Shmalghausen has noticed, that the species staying at the first parts of feeding
chain, are less changeable, but at species of last parts of it the rate of evolution
is very high.
Knowing these facts, it is possible to predict the presence in the future of
strongly changed descendants of modern progressive species, and few changed
descendants of primitive species. So, from bacteria, the lower fungi and the
lower worms any specially remarkable changes can hardly be expected. And among
insects and vertebrates changes can be rather significant. Among plants it is
possible to expect occurrence of new species of flowering and coniferous species
against a background of enough conservative algae, mosses and ferns.
The principle of pre-adaptation: organisms
occupy all new ecological niches (at their occurrence) due to presence
at them properties of genetic pre-adaptation. Its reason is that ability
to the adaptation at organisms is incorporated "initially" and
not connected directly to their interaction with an inhabitancy. Such
ability is caused by practically endless of genetic code and of the information
in genotype of any of organisms. |
At the organism each gene is submitted, as the rule, by set of forms - alleles.
And the shape of the organism (including its physiological displays) is determined
in common by genotype and environment. In the certain conditions of environment
there is the activation of work (expression) of not everything, but only few
genes. Other genes can exist in the organism, can be inherited by posterity,
but their work will be delayed by conditions of environment. But at change of
conditions of habitat they can be “switched on” (certainly if this change of
environment will be adequate, promoting the work of genes). And the organism
can survive in the conditions of environment differing from initial ones, not
changing. Few modern organisms can not make it. The cheetah (Acinonyx jubatus),
remarkable by especial genetic monotony, is those one. In one experiment to
four individuals of cheetah not related to each other pieces of skin from each
other had been replaced, and all pieces have been successfully grafted. At the
basis of this experiment the genetic monotony of this species has been proved.
Obviously, some thousands years ago the number of cheetahs were reduced because
of any reasons up to several families, and then from them it has restored up
to initial amount. But carriers of many genes had died out, and the population
had lost their genes. Uniformity of the genotype will hardly allow cheetahs
to survive, if conditions of life on the Earth will change strongly.
It is possible to think that presence of “reserve” genes in genotypes of organisms
is result of creation or the wise prediction of deity. But it is not so: simply
mutations are not only useful and harmful. There are also plenty of neutral
mutations, which can not be shown in normal conditions. Such mutations are carrying
also by us, by people. So, it was established completely casually, that among
people and monkeys there are individuals which feel the taste of substance "phenilthyocarbamate"
(feeling it as bitter one), and there are also ones do not feeling it. Now this
attribute carries neither advantage nor damage to the survival of the human
and primates. And now we can imagine the situation when for protection against
herbivore animals the plant will begin to synthesize the new poison at the basis
of phenilthyocarbamate. Then ability to distinguish this substance will pass
to the category of vital ones. In other words, organisms have “in reserve” the
greater or smaller amount of the attributes, allowing to survive at change of
the habitat or to occupy actively any new environment.
It is possible to see attributes of pre-adaptations, moving the evolution forward,
at the animals of the past developing land in Paleozoic era. Arthropod animals
have strong armor which protects them not only against enemies, but also against
loss of moisture from the organism. Durability of the armor (it is the external
skeleton) allowed an animal not only to protect against enemies, but also to
keep the constant body shape on the land. Also the armor serves as an excellent
support for muscles, which role on land has strongly increased: Archimedes’s
force of water did not support any more the animal, and at movement it had to
expect only on might of muscles. And on land animals had to leave the jet way
of movement, characteristic for such inhabitants of water as jellyfishes, cephalopods
and larvae of dragonflies: air is much less dense, than water. The crossopterygian
fish already before the colonization of the land had lungs,
powerful flipper-like fins and strong internal skeleton. Its scales were developed
as the adaptation for protection against predators, but they perfectly protect
the organism against drying up. Its kidneys do not emit the limited amount of
salts from the organism, but work for maintenance of constant structure of blood,
they could not only emit out but also keep salts and water in the body. Such
features already presented at animals before the land colonization, also had
allowed them to make the step through the edge of water. Fishes had not cast
themselves ashore by hundreds individuals and had not dry up there, having the
insuperable wish to colonize land gushed over them, as creationists try to present
this process. Not all fishes had developed land habitats, but only that ones,
which were anatomically ready to it. At dipnoan fishes there were (and are)
lungs, but their fins appeared worse adapted to moving overland, than at crossopterygians.
At armored fishes fins resembled crab legs covered with the armour, but, probably,
at these creatures lungs were not present. And only crossopterygian fishes (not
everyone among them, but only representatives of one family) had all complex
of features, allowing developing land habitat.
Not always such step may be made by the most progressive life forms: cephalopods
in Paleozoic were more active and intellectually advanced, than fishes or arthropods.
But at cephalopods during the evolution the reduction of external and internal
skeleton (up to its complete disappearance at modern octopuses) had taken place.
Their single-layered body covers did not protect against drying up (What for
is it? Cephalopods live in the sea, and the sea dries up once in blue moon).
Their kidneys could not support constant salinity of blood (What for is it?
Sea water is very stable: its chemical structure appreciably varies only at
huge time intervals - hundreds million years). Therefore it is possible to draw
the conclusion that fish and the arthropod appeared more pre-adapted to life
on land, than the octopus. They have adapted to life in more changeable conditions,
and resistance against changes of environment has allowed them to develop land.
And cephalopod could not do it, and hardly will can make at all its intelligence.
The law of the genetic variety: all alive
is genetically various, and also tends to increase of the biological heterogeneity. |
Species (genera, families etc.) of live creatures during the history had never
merged and were not united. On the contrary, each steady group of live organisms
(up to the population) by virtue of partial or full isolation from other similar
groups of organisms accumulates differences from them. The slightest differences
in habitat conditions of two related populations result eventually in accumulation
of differences in genofond by virtue of that in different populations carriers
of different genes receive advantages in survival. In philosophy the law of
transition of quantitative changes in qualitative ones is formulated, being
illustrating by the process of speciation.
Some scientists consider that 98 % of species of modern vertebrates have evolved
from approximately 8 species living on the Earth in early Mesozoic. I think,
having compared number of modern vertebrates (over 21000 species of fishes (only
them!) and about 8600 species of birds) with insignificant number of ancestral
species, it is possible to understand, as widely the tendency to increase of
biological heterogeneity of descendants was realized in this example.
At once I want to make the reservation, that there are no rules without exeptions:
some species in nature nevertheless are formed by hybridization, that is the
association of genotypes. Especially frequently it occurs at plants though hybrid
fishes, salamanders and lizards are known. And at plants hybridization even
at super-genera level is possible. And all the same the law of the genetic variety
is not broken - simply the species of creatures with the genotype distinguished
from any of initial forms is appearing. Ancestral species at this process do
not disappear, "being dissolved" in each other, and continue to exist
near to new hybridogenic species. Therefore all the same even in case of hybridogenesis
the amount of new forms will increase.
Certainly, not all groups of modern plants, mushrooms and animals will survive
in the future. It is possible, that high specialization will play the malicious
joke with progressive species, not having given them chances for survival in
changed conditions. Descendants of the staying low-specialized species will
occupy the habitats became free. But each survived species in that case will
give not one, and set of descendant species. The variety of them remain the
stabile, but its bases will be qualitatively other.
The A. N. Severtsov’s law: during the evolution
there is the alternation of aromorphosises (arogenesises) essentially
changing opportunities of species to adaptation and expansion of the inhabiting
area, and periods of allogenesises (idioadaptations) - changes of the
particular order. |
Rule of faltering balance of N. Eldredge
and S. Gould: evolution, as the rule, represents not continuous, but faltering,
saltating process. |
These two laws are to the full illustrated by evolution of any large group
of live organisms: large evolutionary changes happen seldom and pass quickly
(it is possible to judge it by the rarity of fossils of bridging forms at such
sections of evolutional development) and alternate with rather long periods
of small changes, “imaginations of the theme” of large saltations.
So, among plants such large changes were: occurrence of photosynthesis (it had
divided ecological niches of plants and animals); multicellular structure (it
had allowed to increase efficiency of ecosystems and to develop the qualitatively
new level of benthic communities) and breeding with the help of spores (it had
raised efficiency of breeding); forming of organs and tissues (it had allowed
to expand on land); occurrence of secondary growth (some plants have became
treelike); occurrence of seeds (it had sped up the breeding, liquidated dependence
of process of fertilization on presence of liquid water); differentiation of
vegetative and generative sprouts (the increase of efficiency of breeding);
occurrence of flowers and fruits (it has increased speed and efficiency of breeding
and expansion). And each "saltation" was accompanied by flourishing
of certain groups of plants (accordingly): unicellular algae, multicellular
seaweed, rhyniophytons and mosses, ferns and club-mosses, seed ferns, gymnosperms
and flowering plants. But these “saltations” were divided by huge time intervals,
when there was the active speciation of forms with these recently acquired attributes.
It is necessary to note, that it is not necessary to understand as the “saltation”
the “instant” in narrow-minded understanding (for parts of second) occurrence
of any attribute in chosen at will group of creatures (and certainly, it is
not necessary to add here the certain fictious creature named as the deity)
in this process. “Instantly” from the point of view of geology means some hundreds
thousand, and even some million years. Can live beings change with such rate?
Outside of any doubts, they can. Known paleontologist R. Carroll in the book
“Vertebrate paleontology and evolution” mentions about fixed (it is not specified,
at what species) rate of change of species in laboratory conditions, which is
so great, that at such rate of changes the mouse would turn to the elephant
after 10 000 years! Certainly, it is the laboratory condition, instead of natural
one, but R. Carroll’s example shows, as great reserves of evolutionary process
are. It is possible to explain apparent “instant” occurrence of descendant species,
rather strongly changed in comparison with ancestors, by this fact.
The law of the ecological-system orientation of evolution: any evolutionary changes finally are directed by ecological factors and system features of development of evolving aggregation, i. e. the progress is directed by external and internal factors as a whole. |
There can not be the “ultimate goal” at the evolution: changes of organisms occur according to changes of their habitat. Environment forms organisms and determines the direction of their changes. But concrete displays of these changes are determined by internal features of organisms. An example of such changes is the set of well-known to aquarium keepers exotic fishes of families:
Anabantidae: the dwarf gourami (Colisa lalia), the true gourami (Trichogaster spp., Trichopsis spp., Osphronemus goramy), the Siam fighting fish (Betta spp.) and the climbing perch (Anabas testudineus);
Channidae: snakeheads (Channa spp.)
Heteropneustidae: the stinging catfish (Heteropneustes fossilis);
Callichthyidae: armored cory cats (Corydoras spp.);
Cobitidae: the mud loach (Misgurnus fossilis);
Electrophoridae: the electric eel (Electrophorus electricus).
These externally various fishes live in different continents and not always
are related to each other, but all of them have one common feature: in natural
conditions they live in reservoirs with bad oxygen mode. Accordingly, the main
external factor, determined their evolution, was the same: lack of oxygen in
water. But these species differently have adapted to it. Our far ancestors,
crossopterygian fishes of the Devonian period, had solved this problem, having
transformed the swimming bladder, opening in intestines, for air breath. However,
the hypothesis, that the outgrowth of intestines at freshwater fishes has initially
appeared as breath organ, later becoming the organ of maintenance of buoyancy
in water, is more probable. At the fishes listed by me the swimming bladder
either has disappeared, or has became closed and has lost the connection with
intestines. Therefore organs of air breath at all these fishes have developed
by the special unique way (in it the action of internal factors to the evolution
of organisms is shown, in this case – the influence of anatomical features).
At the electric eel oxygen is acquiring by the mucous membrane of the mouth,
at anabantid fishes and dalags – by the modified pair of branchial arches, at
the stinging catfish – by pair of the air bladders opening to branchial cavity,
and at the mud loach and cory cats – by mucous membrane of intestines. It is
the example of the decision of one evolutionary problem (development of air
breath in stagnant marsh water) by different ways!
Considering this law, I want to return once again to propagandized by supporters
of the “divine creation” theory point of view to the evolution as to the ostensibly
simple sorting of every possible combinations of genes, the so-called “dice
play” in all-planet scale. There is no simple and casual sorting! Evolution
of groups of live beings proceeds to the side of environment changes, but according
such means which are in stock at "players". And if such means are
not present at them, “game over” - the species becomes extinct.
Principle of ecological conformity: the form of existence of the organism always corresponds to conditions of its life. |
It can not be other way, because the environment forms shape and physiological
characteristics of species! The shape of species is the compromise between environmental
conditions and internal features of the organism (including character of its
interaction with the habitat).
In one of the "pseudoscientific-popular" books, published in Russia,
the author of these lines had read the statement, that ostensibly bright coloring
and the fantastical appearance of exotic birds and coral fishes is the consequence
of purposeful selection of these species by representatives of certain ancient
civilizations inhabited the Earth earlier (Was it in Mesozoic? In Paleozoic?
Before the Flood?). The poverty of this statement is, that anyone, even the
brightest and fantastical for our point of view, coloring is adaptive, playing
the important role in masking and elements of behavior (breeding, territorial
one etc.) of the present species. Mr. Conrad Lorenz was described in the book
“Aggression. The So-called Evil” (DAS SOGNANNTE BOSE. Zur Naturgeschichte der
Agression) the role of bright “poster” coloring of tropical fishes best of all.
That is why to not run into the plagiarism, I recommend very much to the inquisitive
reader to find this book and to read about supervision of C. Lorenz of coral
fishes.
Rule of conformity of environment conditions of life to genetic predefiniteness of the organism: the species of live beings can exist until then and so long time, as its environment corresponds to genetic opportunities of the adaptation of these species to its fluctuations and changes. |
Because the organism is the product of joint action of external
(features of the environment) and internal (features of genotype and character
of “answer” to changes of environment resulting from it) factors, it exists
only then, when between them there is the certain balance, when genetic reserves
of an organism allow to change in conformity and changes of an environment is
established and by that to keep balance. And one of these factors, the external
one, is practically inexhaustible: ice ages, droughts, falling of asteroids,
change of the oxygen contents in the atmosphere, humidity and rains... Other
factor, internal, has limits: norm of reaction of the organism, which is the
limit of display of external factors inside which the species can exist and
survive. These limits can change by virtue of such phenomenon, as variability
of organisms. The new mutation can expand limits of the adaptive ability of
the organism to any factor. But variability is not fantastic “magic wound”:
it matters only when the speed of environment change is less than probable speed
of change of species attributes. If the environment varies faster, than features
of species, external conditions fall outside the limits of the norm of reaction
of species, and it dies out.
For example, for cephalopods the salinity of water, which should be not less
than oceanic one, has the extremely important value. In the Black and Baltic
seas there are no octopuses though in near and similar to them by temperature
Mediterranean and Northern seas they feel like perfectly. And the trout is especially
sensitive to the contents of oxygen in water: this inhabitant of the ice-cold
mountain rivers perfectly lives in aquarium at the temperature +25°С but with
obligatory saturation of water with the oxygen with the help of the pomp.
In other words, the species, not adapted to the habitat at all, now is not present
and will never evolve in future, because the environment forms the species.
But this formation follows according the genetic resources of the organism,
which limit speed and character of changes.
The law of equivalence of all conditions of life: all conditions of environment, necessary for life, play an equivalent role. |
The organism lives in the “multivariate” world and has the
certain requirements to set of various conditions of the habitat. If one of
these parameters will fall outside the limits of the adaptive ability of species,
it will be fatal for the species.
Mass extinction of species not always takes place directly from the influence
of any factor. We can assert that not all dinosaurs were directly wiped off
the face of Earth by the shock wave after the impact of the asteroid at the
end of the Cretaceous period (because small and delicate bird Presbyornis had
survived after the Cretaceous period!). Undoubtedly, numerous species of these
animals continued to live on the Earth a long time, many centuries after that
accident. But as the results of ecological crisis, conditions of their life
were broken also the mortality had prevailed the birth rate. It is difficult
to tell, what “breaking point” had appeared exceeded, but it is clear, that
the excess was fatal.
This example implies that at the estimation of probable results of any natural
accident it is necessary to consider not only direct, but also indirect harm
for all species and all stages of development of organisms, directly or indirectly
connected with the changed factor of environment. So, for example, the flounder
can live many years in fresh water, but its eggs develop in the sea at the salinity
not less than 15 ‰. The desalination of habitats, thus, is pernicious for eggs
though it is harmless for the adult flounder.
E. D. Cope’s rule: new large groups of organisms evolve not from the specialized representatives of ancestors, but from their rather low-specialized groups. |
If we consider the natural history of any large group of live beings, it is
possible to see, that the ancestor of this group (or family to which it had
belonged, if the present ancestor is not found) represents the creature, having
no any special, strongly expressed features of specialization. So, ancestral
forms of hoofed mammals of various modern orders were very similar against each
other and resembled any simplified children's picture of the certain abstract
four-footed creature: the big head, teeth of the omnivore, short paws with five
fingers, massive body and long tail. It is not the hippopotamus, the excellent
swimmer; it is not the giraffe, whose world reaches above our heads; it is not
the predatory Mesonyx (extinct) with mighty canines and sharp claw-looking hoofs;
it is not the swift-footed horse or the antelope; it is not the massive elephant
with long trunk. It is nobody of them and simultaneously all of them as a whole.
Just as the ancestor of insects is not the butterfly with color wings and proboscis
mouth, not the beetle with strong elytrums, not the grasshopper with strong
hind legs, not the fine hopping wingless flea, not the soothsayer with its forward
seizing legs. Primitive flying insects had two pairs of wings with rich net
of nerves, ordinary-looking, almost uniform walking legs and gnawing mandibles.
Ancestors of large groups of live creatures are not bad adapted to the big spectrum
of conditions of the habitat, that makes for them possible fairly good (though
not perfect) inhabiting in various environments. And the variety of inhabitancies
occupied with ancestral species makes possible variety of descendant species
and different development by these descendants of their habitats.
Crossopterygian fishes, apparently, look here the unique exception. In comparison
with other fishes they were rather specialized to the inhabiting in very special
conditions: swamp-like shallow reservoirs with low oxygen contents and rich
thickets of plants. But they had become ancestors of huge group of the ground
tetrapod animals being dominant species on the modern Earth. Is it the exception?
I do not think so. If to look from other point of view, crossopterygian fishes
appear the most unspecialized ground vertebrates! So rule of E. D. Cope is not
broken completely.
Ch. Darwin’s principle of divergention, or H. F. Osborn’s rule of adaptive radiation: the phylogenesis of any group is accompanied by its division to the number of separate phylogenetic branches which miss in different adaptive directions from the middle initial condition. |
As it had been written earlier, the ancestor of large group of animals is not “the professional of the survival” in the certain habitat. It is the species using the set of resources of the habitat, but each resource is used not completely. The opossum among modern animals is those species, for example. It can catch small mammals and birds, fishes, eat berries and greenery of plants. But the cat is the best hunter, than the opossum, the otter surpasses it as the fisher, and the rabbit is capable to use for feeding more species of plants, than the opossum. But the opossum do not remain hungry if in the forest there are no mice, or in the river there are no fishes and crustaceans. It will live due to those resources, which can not be used by the cat, the otter or the rabbit because of their specialization. So, the opossum is the best fisher, than the rabbit, the best bird-catcher, than the otter, and the best herbivorous, than the cat. And its advantage is in it. But advantage of the otter above the opossum that it can catch almost any fish, and the opossum - only the most sluggish or feeling bad one. The cat easily catches even the most agile mouse or bird when the opossum will catch one having no place to run out of it. And the rabbit will live, eating such grass which the stomach of the opossum is not capable to digest. But the rabbit is the same bad fisher, as the otter is the bird-catcher or the cat is herbivore. Differently, the specialized species “refuses” an opportunity of development of any other resources for the benefit of more full development of certain one of them. It gives the advantage to it: such species do not compete with each other for food. Galapagos finches and the Hawaiian honeycreepers are those among modern animals. These examples migrate from the book to anther one and are enough “trite” ones. But there are also other examples, illustrating this phenomenon: fishes of cichlid family (Cichlidae) in Great African lakes. From few related ancestral species in these lakes species using different sources of forage and having completely different habit of life, had evolved. Inhabitants of lake Tanganyica, species of genera Lamprologus, Tropheus, Julidochromis and others live in the zone of stony coastal screes. These fishes keep among stones, finding shelters in them. In rocks, besides these fishes, Chalinochromis, Ophthalmochromis, Petrochromis, Perissodus (for these species the feeding with scales and eyes of other fishes is known) keep. Above sandy beaches species of genera Xenotilapia, Cyathopharynx, Callochromis and some others live. In thickets of reed near river outfalls Oreochromis, Astatoreochromis and Limnotilapia live. Depths of lake (about 140 meters) Trematocara and Limnochromis have developed. And in open water, far from coasts, schools of Bathybates, Cyprichromis, Perissodus, Boulengerochromis swim. Someone from these species eats invertebrates, there are active predators, herbivores, planktophags and scavengers are among them. Thus, these species avoid the competition with each other, occupying different habitats and eating different food. And as a whole evolving group of animals has maximum full developed all habitats and food resources given by the nature.
Ch. Deperet’s rule of progressive specialization: the group entering the way of specialization, as a rule, in the further development will go to the way of more and more deep specialization. |
It is simple to explain this phenomenon: the specializing species loses many features of anatomy and physiology of the ancestor, which allowed to survive in other conditions. The missed organs and systems of organs, according the L. Dollo’s rule, do not appear again, therefore the species can evolve only to the way of perfection of the remained attributes.
O. Ch. Marsh’s rule: more specialized forms, which genetic reserves for the further adaptation are reduced, have more chances of extinction. |
is closely connected to thу previous rule. The matter is that the genotype of the specialized species also is impoverished, it has less genes, which can change and form new combinations. And genes and their combinations are the basic material for action of evolution. At change of an environment at deeply specialized species the genes allowing it to survive can not appear.
The E. D. Cope’s and Ch. Deperet’s law of increase of the size and weight in phylogenetic branch: in process of historical development of the group of live creatures its surviving representatives increase the size and then die out. |
Look at the family tree of many groups of large animals: dwarfs
stand in the beginning of their evolutionary branch. Fossil proboscidean Moeritherium
was large pig-sized, cetacean Ambulocetus was about 3 m long including
the tail, "horse" Eohippus was as big, as small dog, dinosaurs
Coelophysis and Pisanosaurus have weighed no more than 50
kg, rhinoceros Hyrachius and brontotherium Eotitanops were
pig-sized mammals, predator Miacis was not larger than modern marten.
But their descendants are huge! Dinosaurs, elephants, rhinoceroses and whales
are the recognized giants of the planet. Brontotheriums, less known to the average
man, have surpassed rhinoceroses in size. And the polar bear, tiger and sabertooth
cats, alive and dead not unfoundedly had induced and induce now horror to people
by their size and might. Fossil turtle Proganochelys about 1 meter
long seems large, but in comparison with fossil 5-meter Colossochelys
and 4-meter Archelon, and also modern 3-meter leatherback turtle Dermochelys
it looks as the real pigmy.
But it is uneasy to be the giant. Giants are whimsical: they demand plenty of
forage and thus are capable to exist only in stable conditions of habitat. Therefore
during catastrophic changes in the natural environment giants become extinct
at first. Occurrence of giant species in evolving group of alive creatures shows
that the group has found the stable and rich in forage ecological niche, where
there is no strong competition, that it has achieved the certain evolutionary
success.
Rule of constant number of species during the stationary evolution of biosphere: the number of appearing species on the average is equal to number of extinct ones, and the general variability of species in biosphere is the constant. |
The amount of species can not be constant: during global natural
accidents mass extinction is not a rarity: on the border of Mesozoic and Cenozoic
about 60 % of species had died out. Probably, extinction of the big, interesting
and mysterious dinosaurs has given the “public resonance” to this extinction.
But the more terrible extinction on border of Paleozoic and Mesozoic, destroyed
about 90 % of species on the Earth, has left in shadow, was much more destructive!
Big or small extinction for any time reduces the number of species on the Earth,
but at the restoration of normal conditions survived species start to grasp
the places of an inhabiting had became free. Areas of the species inhabiting
extend; their various sites are diverse, that results in various directions
of evolution of species uniform before it, and in occurrence of group of different,
though also the related species, approximately replacing species dyed out earlier.
Borders of distribution of the present species can not coincide with areas of
the former, dyed out species as there is no two completely identical under requirements
to environmental conditions of species. But the variety of species is defined(determined)
first of all by variety of ecological niches "offered" by an environment.
Certainly, it is difficult to expect simultaneous occurrence of millions species
of alive creatures in epoch of life origin. But it was not stationary stage
of biosphere evolution! Life had only started to develop and to colonize the
planet, expanding borders of biosphere in depths of ground and ocean and to
tops of mountains.
It is necessary to tell some words about the “stationary condition” of biosphere.
In general I think it is possible to name rather “stationary” only very small
part of biosphere evolution. As a whole the biosphere passes the way of development
connected with the evolution of the Earth as the planet and the Sun as the star.
At the Sun there was the period of “youth”, when it only had began to warm up.
Now the Sun is the “mature” yellow star. But through some billion years there
will come inevitable “old age” of the star – the transformation of the Sun to
the “red giant” that will be accompanied by the catastrophic changes excluding
the opportunity of existence of protein life type on the Earth. For this reason
its author has entered the word “on the average” into the formulation of the
law, that shows, in my opinion, the conditional character of the concept of
the “stationary condition of biosphere”, which nevertheless slowly varies. At
the small part of its evolution it is possible to disregard some very slowly
varying factors (for example, evolution of the Sol). But considering very big
parts of biosphere evolution, it is necessary to remember, that not only bulbs
can fuse.
I. Shmalghausen’s rule of amplification of biological systems integration: biological systems during evolution become more and more integrated, with more and more advanced regulating mechanisms providing such integration. |
If to compare progressive and primitive organisms, it is possible
to notice, that progressive organisms perfectly operate as a unit, but badly
tolerate the destruction. For example, the hen with the chopped off head convulses
only some minutes, and the turtle with crushed head stills alive during some
weeks. And such unpleasant event does not make difficulties to the earthworm:
it simply will grow up a new head. The chopped off head of the eel or the monitor
lizard can bite some hours after chopping. The flat worms cut to some pieces,
restore the whole animal from each piece. At starfish Linckia from each cut
off beam the whole star can restore. Crustaceans easily restore the lost legs
and antennas, and octopuses regenerate tentacles. Among mammal sloths and anteaters
tolerate the hardest wounds: the skull of fossil sloth Megatherium was found,
which at life of an animal was shattered (probably, by the rockfall or the fallen
tree), but then has grown together and faithfully served to the owner a long
time after it. And can the man restore only the amputated hand or leg (I do
not mention the surviving with the head shattered in bloody pulp)? Certainly,
the answer is “no”. In general, primitive animals tolerate every possible damages,
while among progressive animals ability to regeneration amplifies more easy
only at sedentary and inactive forms. The fast destruction of the injured organism
of the progressive animal shows the close interrelation of its organs and their
systems.
But it is more difficult to look after these connections in systems of the super-organismic
level. It is difficult to judge, how strong interrelations in natural ecosystems
of the past eras were, because fossils are obviously incomplete. In the modern
world it is possible to see set of connections between the species, based on
parasitism, commensalism, symbiosis and antagonism... It is difficult to tell,
as far as they were strong and numerous in ecosystems of past geological eras.
But it is doubtless, that thickets of rhyniophytons at the bog of an early Devonian
were much poorer in connections between species, than bogs of the Carboniferous
period and the more so of modern bogs. You see the variety of species is increasing
in due course, and connections of each species with others are individual and
unique. And the increasing of number of the species in the ecosystem means the
increasing of number of these connections. It is possible to assume, that in
the future these connections will be not less various, than in the modern world.
Thus, it is possible to tell, that evolution is not the casual sorting of all
possible and impossible combinations of the genes embodied in alive creatures.
It proceeds according the principles and laws which can completely exclude the
significant amount of directions of change. Loss of any attribute narrows the
spectrum of changes, and its acquisition considerably expands adaptive opportunities
and results in formation of the greater or smaller amount of new species. Evolution
is not a simple sorting of attributes, dictating by certain superior force (we
shall name it as the “God”), and the development is limited by set of factors,
external and internal. Change of species is not end in itself and rather the
compelled necessity, dictating by changes of world around. Each species of alive
creatures is the product of combination of accident (mutations, set of genes,
direction of changes of the environment) and appropriateness (direction of the
adaptation to this environment).
Human fossils in the sediments of the future
Picture by Sauron