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. Roulliet’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 (it is possible, 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. Such species are trees Ginkgo
and Degeneria, tadpole shrimp Triops, mollusc Nautilus, marsupial mammal
opossum Didelphis, for 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:
-- Organisms, protecting against predators only by high breeding rate. Such
strategy is characteristic for bacteria, unicellular organisms and some multicellular
forms forming plancton.
-- Organisms having passive protection against predators (shells, crusts,
spikes) – they are molluscs, crustaceans, higher plants.
-- Organisms, capable to protect against predators due to speed of moving.
-- 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 from 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: dalags (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°Ñ 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 genus 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,
planctophags
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. March’s rule: more specialized forms, which genetic reserves for
the further adaptation are reduced, have more chances of extinction.
is closely connected to that 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 proboscid Moeritherium
was large
pig-sized, cetacean Ambulacetus 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 no more 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 Sun). 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).