Alternative evolutionary theories: Lamarckism, catastrophism, saltationism. Synthetic theory of evolution. Alternative evolutionary theories Synthetic theory of evolution

"It's not about performing here.

philosophy against science, but vice versa
about the desire to defend science there,
where “scientificness” appears only as
formal expression mask
(not to say dragging)
unfounded and not related to science
relations of arbitrary intellect-
aesthetized mythologemes,
quite primitive in essence,
but accessible and seductive... for
the general public..."

Makhlin V. L.

What are the driving forces of biological evolution?

There are two fundamentally different approaches to answering this fundamental question.

In accordance with the first, the phenomenon of changing the forms of living things is a random process determined by two, although different in essence, but for all that - random factors. These are chaotic mutations and natural selection. All versions of Darwinism, including the most modern ones, are based on such ideas. Life is only a certain ephemeral (against the background of overwhelming cosmological scales) phenomenon, and at the same time, mind as a cosmic factor is also something random and transitory.

According to the second approach, the process of evolution is fundamentally natural, which manifests itself even against the background of many random factors. This concept is known as nomogenesis.

In modern science, the Darwinian approach dominates; the “silent majority” of biologists are confident that it is the only possible explanation of the phenomenon of evolution, that there is and cannot be a reasonable alternative to it. Is this really so? Is a scientific alternative to Darwinism possible?

The questions posed here give rise to a whole cascade of new ones. And the most important of them was asked a very long time ago - is Darwinism itself a truly scientific theory? Also, a negative answer to it was given a very long time ago and well reasoned. And yet there is a way out of the impasse, and the prospect of obtaining a scientific explanation of the phenomenon of evolution is associated with the concept of nomogenesis. Great Russian biologists took part in its formation and development: L. S. Berg, N. I. Vavilov, A. A. Lyubishchev, S. V. Meyen.

The proposed article is a brief outline of this theory.

The complete opposite of the isolation of Darwinism from philosophy is non-classical biology, the creator of which, the largest Soviet scientist A.A. Lyubishchev, was, as the “Bulletin of the USSR Academy of Sciences” writes, a professional of the highest rank in both philosophy and biology. “Lyubishchev’s works are a unique collection of facts that are difficult and undesirable for current biology.” In particular, he argued that it was impossible from the standpoint of Darwinism to indicate “what selection factor forced one of the crayfish to insert a grain of sand into the vestibular apparatus after each claw molt. He was interested in why the colored spots on the wings of butterflies behave against the background of veins and scales like a pattern on printed calico, unrelated to the arrangement of the threads.” This fact alone undermined the fundamental belief of Darwinists that the properties of the whole are determined by the properties of the parts.

A.A. Lyubishchev convincingly showed that Darwinism is not even a scientific theory - it is only an assumption not proven by any facts. And most importantly, Darwinism has no essence, no core for the theory: random selection turned out to be false, and Darwinism does not offer any other drivers of Evolution. It was the scientist who was searching for such true engines of Evolution.

But first, it makes sense to recall the main objections raised against the Darwinian approach to explaining evolution.

1.Why can’t Darwin’s concept be considered scientific?

The modern existence of Darwinian teaching has the character of some strange duality, some kind of paradox. On the one hand, this concept is recognized as the official doctrine of modern academic science. It lies at the basis of what is commonly considered the scientific picture of the world. This is the topic of standard university courses and school exam tickets. Anyone who doubts its reliability risks being branded an ignoramus and an obscurantist.

But with all this, every person who criticizes Darwinism is, as it were, banging on an open door - after all, its purely scientific inconsistency has been proven long ago and in countless examples. Let's remember the aphorism Lyubishcheva: "Although a Mont Blanc of facts has been collected in favor of the theory of evolution, the Himalayas of facts speak against it". Here is just a short list of the most frequently cited arguments.

1. Critics say that the theory of evolution is too vague to be strictly proven or disproved. “Darwinism has always been presented logically and sloppily.” In addition, it is not something homogeneous and represents a whole set of sometimes strongly contradictory interpretations (as many Darwinists, so many Darwinisms). The situation here vividly resembles the variety of theories of the ether on the eve of the creation of the theory of relativity.

2. Critics also point out that everything presented as demonstration examples, supposedly proving Darwin’s theory, such as the presence of a similar genetic structure in similar organisms, rudimentary organs, data from breeders, etc., upon closer examination, can find something else quite reasonable explanation. The example of industrial melanism of Biston Betularia butterflies, which passes from one popular science book to another, is no exception here.

3. The theory of evolution is based on the idea of random, undirected mutations. With all this, even approximate, qualitative estimates of the probabilities associated with such processes immediately give a catastrophic result, depicted in decimal fractions with a huge number of zeros after the decimal point. No explanation has been given for this. The usual references to the duration of the evolutionary process (billions of years) and the huge number of individuals participating in selection are completely declarative and do not explain anything.

4. Contrary to popular belief, the discoveries of modern biochemistry and genetics. do not strengthen, but weaken the already ephemeral positions of Darwinism. It is becoming increasingly clear what a complex and finely balanced complex of physical and chemical processes corresponds to living things. Therefore, the prospect of explaining evolution by the game of chance seems increasingly ephemeral. (In order for a mutation to be favorable, a miraculous coincidence is required, a synchronous mutation of a whole set of genes that correspond to various organs, systems and functions precisely tuned in the process of life.)

5. In the classical version of Darwinism, the process of evolution is considered as continuous and gradual. Darwin himself, as we know, seriously believed, for example, that a bear, through a process of continuous, “plastic” deformation, could eventually turn into a whale. Evolution is a kind of laminar process, a smooth flow of one form into another.

There are very serious reasons to think that this is not so. First of all, paleontological material is replete with huge gaps, suggesting that the set of permissible forms of life is by no means continuous, but forms a multidimensional matrix consisting of subsets with well-defined boundaries. The same material testifies to the sharp mutations that have occurred repeatedly in the history of living things and immediately captured vast regions.

The experience of breeders speaks to the same thing: the changes that can be achieved through selection have clear limits set by “nature itself.” Therefore, although it can lead to outwardly very significant changes, its possibilities are limited. Here it may be appropriate to compare it with the deformation of an elastic body, which is possible only up to certain limits, and then either leads to destruction or a return to its original state. This means that although external changes may seem very large, the fundamental structures and functions remain unchanged.

So, a biological species is a fuzzy cluster of many admissible states. The transition from one to another is impossible due to a sequence of continuous changes. All this is very similar to some physical, and in particular quantum systems, which have a discrete set of allowed states, the transition between which can only be a jump.

Thus, evolutionary theory found itself between Scylla and Charybdis. The concept of gradual change is contrary to known biological facts. But the idea of rapid changes also faces the insoluble problem of the insignificant probability of a random coincidence of simultaneous favorable mutations.

6. But even if you close your eyes to all these insoluble contradictions, and take the word of the Darwinists that they still give a correct, at least qualitative, explanation of microevolution, that is, evolution at the lower taxonomic levels, the no less serious problem of macroevolution inevitably arises , that is, the evolution of taxa of higher levels. It is necessary to explain why, for example, insects and mollusks, and not just more advanced bacteria and algae, were subsequently formed from primitive bacteria and algae. There is no answer.

7. As is known, the modern, “synthetic” version of Darwinism is an interpretation of Darwin’s concept in the language of genetic theory. And although the correlation between the genetic code and the form of the organism is beyond doubt, the existing theory is unable to explain how the genetic code determines the form of the organism in the process of ontogenesis. And here is another reason that evolutionary theory does not explain the process of evolution: a key link is missing in the logical scheme.

We have listed the most obvious and frequently heard critical arguments. They have long been well known and have been repeated many times by the most authoritative biologists. But, as we see, the effectiveness of such criticism turned out to be close to zero: Darwinism continues to be the official doctrine of academic science to this day.

The question inevitably arises: should the concept of natural selection then be considered truly scientific? We emphasize that this is not about the truth or fallacy of Darwinism, but about whether it is a “ordinary” scientific theory. Maybe, after all, this is a phenomenon of a completely different nature, only imitating the external signs of science? Many people believe that evolutionary theory, in the generally accepted sense, never existed. What was called theory was only a series of interpretations. There is no need to remind that a full-fledged scientific concept is capable of not only consistently and uniformly explaining all experimental material, but also predicting new, previously unknown phenomena.

Did this concept predict the existence of phenomena that are fundamentally inexplicable within the framework of competing theories? Was she able to offer at least one experimentum crucis? “For one hundred and fifty years of its existence, it not only failed, but also developed among its adherents such persistent indifference to the problem of its own validity that it is now difficult to say whether there is anything in nature that can overshadow the Olympian serenity of its adherents.

So maybe those critics of the theory of evolution are right who believe that Darwinism is only an ideologeme that has taken on the guise of a scientific theory? After all, a hundred years ago, our famous compatriot N.Ya. Danilevsky wrote that the theory of evolution is not so much a biological as a philosophical doctrine, a dome on the building of mechanical materialism, which alone can explain its fantastic success, which is in no way explained by scientific merits. The irremovable gap between the autonomously developing empiricism and Darwinian natural philosophy, which lives according to its own internal laws, not only does not decrease, but is constantly growing.

Then the main reasons become clear that, despite the obvious futility and dead end, Darwin's theory of evolution remains almost undividedly dominant. We have already said about one of them: Darwinism is the most consistent embodiment of the “line of Democritus”. The ideological merits here are beyond praise, but as for the facts, they will somehow be settled.

Another reason is also on the surface. As often happens, even a concept that has failed many times can exist for a very long time, as if by inertia, if it does not have a sufficiently developed alternative. And here, for the sake of objectivity, it should be said that, until recently, Darwinism really did not have one .

The situation changed significantly after the work of a domestic biologist Sergei Viktorovich Meyen the main provisions of the nomothetic theory of evolution were formulated. It should, of course, be borne in mind that Meyen had great predecessors.

2. Nomogenesis

The concept itself is nomogenesis, and the arguments in favor of the fact that, contrary to Darwin, evolution is by no means random, but a natural process, have been thoroughly and convincingly substantiated. Lev Semenovich Berg in his classic works of the 20s, of which the main and most famous is " Nomogenesis, or evolution based on patterns".

Berg formulates the problem this way: is evolution a random process, which is determined by only two factors: chaotic mutations and natural selection, or, on the contrary, is it a fundamentally natural process, the identification of a certain tendency, an immanent law that directs its course?

In this formulation, the question may seem not entirely correct, and even pointless, since processes that are basically random can obey very strict statistical laws. More precisely, its essence can be understood from a simple analogy: although the development of an individual organism is influenced by many random factors, there is no doubt that the main, determining factor here is internal information embedded in the genes. Its entire history, curriculum vitae, is the unfolding, the implementation of a program, on which only depends what will grow, for example, from a given seed - a birch or a pine

The entire evolution of the biosphere is, according to Berg, the unfolding of some kind of Law, or perhaps it would be more correct to say, a multivariate program, which also contains numerous ways of its implementation.

That's why Berg called his concept nomogenesis, contrasting it with the Darwinian concept tychogenesis, i.e. development based on chance.

Can we today, at least in the most general outlines, imagine what this law looks like? The answer is negative, but our ignorance does not mean that there is no such law: “ignorance of the law does not relieve us of the responsibility” to understand that it exists.

Let us imagine that a certain mathematician studying tables of random numbers is surprised to discover in them stable repetitions, “motifs,” “rhythms and rhymes,” “homologies,” the presence of which cannot in any way be explained by the play of chance. Let him then be able to find something similar in other sequences obtained with the help of independent and different generators.

What hypothesis does such a mathematician have the right to put forward? He can, first of all, assume that the series he is studying are not random at all, but are a rather intricate manifestation of a previously unknown natural pattern.

In his works, Berg summarizes a huge amount of factual material accumulated by the beginning of the 20th century, which testifies in favor of the nomogenetic nature of evolution. This material speaks of the numerous “rhythms and rhymes” present in the system of living forms, which cannot be explained on the basis of chance. By way of illustration, we will briefly recall only a few of them. (This makes all the more sense since Berg’s classic book was published in our country only twice, with a total circulation of 10 thousand copies, and was always practically inaccessible to the reader. For all that, books of the Darwinian persuasion were always sold in large editions. - note at the bottom of the page)

A) Anticipation of characters (phylogenetic acceleration).

It is known that in the embryonic phase signs of those stages through which the evolution of this group supposedly passed are observed. At one time, E. Haeckel, an ardent supporter and propagandist of Darwinism, formulated a rule called the “biogenetic law”: ontogeny repeats phylogeny. Pictures illustrating this rule have been reproduced in biology textbooks for many decades.

For some reason, it is believed that it serves as a direct argument in favor of the Darwinian concept, although it can only be understood as evidence that evolution generally takes place, which, of course, few doubt.

Much less frequently discussed is the fact that the opposite, time-symmetrical phenomenon also occurs: “individual development can not only repeat phylogeny, but also precede it.” This rule applies not only to individual organisms, but also to their entire groups: the phylogeny of any group can be ahead of its time, realizing forms that are normally characteristic of higher-ranking organisms in the system.

This means, in particular, that the characters that appear as a result of anticipation could not be obtained as a result of the action of the Darwinian mechanism. Like individual development, evolution is a process of unfolding and implementing an already existing program.

b) Convergence.

The same thing is convincingly evidenced by the phenomenon of convergence: in taxonomic groups, often very far apart from one another, surprisingly similar characters appear. A textbook example is the similarity in the structure of the eyes of a human and an octopus.

There are countless other examples, and Berg mentions that “lungfishes and amphibians show in their organization a number of surprising similarities, so striking that previously they were inclined to produce amphibians from lungfishes.” It is now firmly established that this is not so, yet many correspondences appear in two independent evolutionary branches. Convergence affects all vital, basic systems of the body: skeletal, circulatory, nervous, etc.

One gets the impression that evolution was conceived by one designer who applied similar solutions to fundamentally important problems.

V) Monophyletism or polyphyletism?

According to Darwin, all the many forms of life arose from one or very few primary forms (monophyletism), and all further development proceeded only divergently. The author of “The Origin of Species” is forced to insist on divergence in order to explain, at least in words, how such a fantastic diversity of living forms could arise. Monophyletism and divergence are fundamentally important assumptions in the logical scheme of the theory of evolution, which actually play the role of its additional postulates.

Meanwhile, paleontological material indicates that, along with the phenomenon of convergence, there is an equally amazing phenomenon of polyphyletism, when similar, sometimes indistinguishable forms arise from completely different roots. But a very important conclusion follows from this: the diversity of living forms should not be depicted as a continuously branching family tree. but a multidimensional matrix, arranged in such a way that its different cells can be reached in different ways.

G) Homologous series.

The phenomenon of homological series has been known for a long time, but it was thanks to the classical works of N.I. Vavilov that its fundamental meaning became clear. It consists in the fact that in plants of related species there is a stable repetition of the same characteristics. Vavilov demonstrated this with the example of the diversity of wheat species. (In soft wheat there are variations with awned, awnless, semi-awned ears. There are also color variations: white-eared, red-eared, etc.. Species related to soft wheat have the same variations.)

Berg knew well about the results of the work Vavilova and in his book he clearly pointed out its nomogenetic meaning.

Let's summarize some results. A number of general biological phenomena indicate that the process of evolution cannot be described within the framework of Darwin’s scheme, even qualitatively. On the contrary, it should be considered as the unfolding, implementation of some kind of multivariate superprogram, that is, as a process based on a certain law, “nomos”. Berg does not discuss the question of what serves as the source of these “nomos”, these laws.

What is the fate of Berg's concept? What kind of reception did she receive from her contemporaries? It is not surprising that he is very cool, if not negative.

What about abroad? The picture is the same. Does this mean that the facts cited by Berg found a reasonable explanation in the modernized, “synthetic” version of Darwinism or were refuted by someone? Neither one nor the other. The factual foundations of the concept of nomogenesis not only have not decreased, but have significantly strengthened.

3. Evolution without selection?

The bill presented by the author of “Nomogenesis” to the theory of evolution has not only not been paid, but more and more new lines are appearing in it. Therefore, the desire to find a way out of the “endless dead end” of the all-conquering Darwinian teaching is inevitable. In this sense, the book of a famous biologist, Nobel laureate Lima de Faria with an expressive name " Evolution without selection. Autoevolution of form and function"is one of the most famous. It is significant that the arguments given by the author against Darwin’s theory largely repeat the arguments Berga, who wrote his works more than eighty years ago.

So what is autoevolution? In a very brief presentation, the concept looks like this. Biological evolution is determined by three preceding it: elementary particles, chemical elements and minerals. In all these processes, natural selection or something similar to it, even if it took place, was a secondary factor.

The main constructive process is self-assembly, a special combination of components specific to each level. In this case, there are strict rules of fixation (analogous to heredity) and changes (analogous to mutations) inherent in their organization.

Thus, what may seem random is, in fact, one of many variants of the natural.

The following rules apply for all three levels:

"... a) all forms and functions arise from several basic forms and functions; b) all new forms and functions arise ... exclusively through combination; c) the principles of symmetry and asymmetry are involved in their organization; d) the number of options is limited and small; e) order prevails at all levels."

At the biological level, the same rules apply, and therefore the evolution of living organisms is determined by evolutions at previous levels.

"... Each new level appears as a typical innovation, not because it creates something fundamentally new, but because it represents a continuation of only a very few already limited combinations of previous levels."

4. Systematics - a window into ontology.

"People, lions, eagles and partridges, horned deer,
geese, spiders, silent fish that lived in the water,
starfish and those that were not allowed
see with the eye - in a word, all lives, everything
lives, all lives..."

A.P. Chekhov "The Seagull."

In biology, the prevailing opinion for a long time was that systematics is secondary in relation to phylogeny. According to Darwin, the family tree is the only system of organisms. But more and more firmly established facts indicate that this position is not only not the only reasonable one, but is simply wrong. For the substantiation and detailed development of the thesis that the natural system of living forms has its own internal, timeless, immanent in the very nature of the living foundation, science is obliged to classical works Alexander Alexandrovich Lyubishchev .

Before Lyubishchev, most of his colleagues legitimately believed that systematics was a purely auxiliary discipline, something like bibliography, and therefore its problems could not be problems of primary importance.

There is no doubt - the fossil record, that is, the story of how some forms of life were replaced by others, reads like a fascinating novel, but we must not forget that the events it talks about are based on two extremely simple, “ontologically banal” factors - chance and natural selection. There is nothing more behind this, and the sight of a system of living forms is a little more meaningful than the configuration of cracks on glass, where all philosophy is exhausted by the words: “It so happened...”

Back in the twenties, Lyubishchev clearly understood that it was impossible to build a taxonomy on the basis of Darwin’s postulates. We need some fundamentally new (or well-forgotten old?) approaches. In a work dated 1923, he writes: “The system can be built either on Plato or on Darwin and Spencer; building a system from Darwin’s philosophy turned out to be an illusion; it is necessary to build a system, abandoning the evolutionary approach.”

In the final chapter of another work, this idea is developed in somewhat more detail: “... a species as an idea; organisms are pure forms; the problem of expediency as a special case of world harmony, increasingly losing its utilitarian character and increasingly acquiring an aesthetic character; beauty as absolute reality(italics by A.A. Lyubishchev - A.M.); the development of organisms as the embodiment of an idea with the ultimate goal of the triumph of spirit over matter; all this is the revival of genuine platonism, the main and only serious opponent of Darwinism, understood as a philosophical system, and not just as an evolutionary doctrine" [ibid., pp. 66-67]. In other words, Darwinism makes no sense to improve, correct, modernize, etc. etc., just as it is pointless to correct and improve the Ptolemaic system by adding new epicycles.

But what relation can the “fundamental question of philosophy” have to the problems of systematics?

5. Atoms and holons.

The founder of the materialist tradition, Democritus, as is known, taught that everything in the world consists of atoms and emptiness.

Or: in the world there is no Nothing except atoms and emptiness. Here is not only a statement about the existence of a limit to the divisibility of matter, but the most important metaphysical principle, according to which all things are aggregates of varying degrees of complexity. This approach is called reductionism. Here, any whole ultimately reduces to the sum of its parts. The parts precede the whole.

Plato proposed a fundamentally different - holistic view of the world. He, of course, understood perfectly well that among the things around us there were more than enough aggregates. But Plato postulated the existence of such unique existential objects, the principle of structure of which is directly opposite to the aggregate principle. In them, the whole precedes its parts and determines their properties.

Integrity, according to Plato, is a fundamental property that cannot be reduced to any interaction of parts. (Using modern analogies, we can say that this is the same fundamental property of matter as gravitational, magnetic, etc. interactions.)

Plato called the objects in which this property manifests itself with the greatest completeness and clarity the Whole. In Greek this word sounds like holon. (Here we can also give modern analogues: photon, electron, graviton, etc.)

It is important for us to understand here that the essence of Plato’s statement cannot be reduced to the incomprehensible Diamatian formulas that “the whole is greater than the sum of the parts,” etc., which precisely because of their incomprehensibility fit perfectly into the general reductionist context and serve it only as some kind of verbal trinkets.

It is fundamentally wrong to think that the holon is a certain limit achieved by a complex system with an infinite increase in the number of its constituent elements and interactions between them. Plato's statement is much less obvious and much more meaningful: there are objects in the world whose integrity is fundamental, primordial, i.e. irreducible to any interaction.

In aggregates, integrity is a consequence of interaction. There is no interaction between parts and there is no integrity. In the holon, integrity is “primary” and what sometimes looks like interaction is only a correlation of the behavior of parts, inexplicable within the framework of a reductionist approach, in which this integrity is most clearly manifested. (One possible example is the well-known quantum exchange interaction, which makes molecules stable.)

The demonstration model of the holon for the great Hellene is a living being. Cosmos is a holon of holons, consciousness is also a holon.

At the end of the 19th century, reductionist metaphysics was dominant. Atomism, mechanism, Marxism, Darwinism, Freudianism, etc. - these are just various developments of the theme of Democritus, carried out with varying degrees of consistency and frankness. By the end of the 20th century, the situation had changed radically and continues to change rapidly. Of course, reductionism is still very influential, but its strategic positions have been weakened. And there are very serious scientific reasons for this. The existence of fundamentally integral objects, holons, has been proven experimentally. These are the essence of objects of quantum physics. (It is worth noting that it is precisely those objects that physicists, having experimentally discovered, initially interpreted as atoms, there are in fact the simplest systems that exhibit the properties of holons. Therefore, it would be more correct to say not atom hydrogen, and holon hydrogen, etc. - Note at the bottom of the page.) Quantum physics is the first and most successful holistic scientific research program, holism in action.

Does this mean that, under the impression of these facts, the scientific community is about to agree to accept objective idealism as the metaphysical basis of the scientific picture of the world?

This will happen sooner or later, but not very soon. After all, reductionism is still very influential precisely in the sciences about living things, that is, precisely in those objects that for Plato were synonymous with the Whole. And although physicists have long since departed from Democritus in the foundations of their science, the reductionist hopes of biologists in physics and chemistry do not become less ardent with time.

Contrary to the Himalaya of Facts, most biologists view life as a very, very complex automaton. The evolution of living forms is interpreted in the spirit of Darwinian teaching as an intricate result of random undirected mutations and natural selection.

6. Metaphysical Focus

Lyubishcheva cannot be considered an unconditional supporter of nomogenesis in Berg's edition, but it is his works that constitute the philosophical center, the pinnacle of the Russian nomogenetic tradition.

He clearly connected it with Platonic metaphysics, Plato's line in science and culture. . He realized that the stagnation in theoretical biology, including the seeming dead end of the problem of evolution, is due to the dominance of the reductionist paradigm. This means that it is necessary to update the metaphysical foundations of biology as a whole.

In the Platonic tradition, everything that exists is understood as a hierarchy of holons. An individual organism, biocenoses of various levels, all living things as a whole and, finally, the Cosmos are the essence of holons.

As we have already said, the real correlate of the philosophical concept of holon was found among quantum objects. Very meaningful models of holons can be found both among other physical objects (holograms) and mathematical structures (Mandelbrot set). Hologram (it would be more correct, of course, to say - hologram!) has the remarkable property that each sufficiently large part of it contains information about the whole object.

This means that if the world is a Holon of holons, then in it an insightful thinker has a chance to find such phenomena in which, as if in focus, the principles of the world order as a whole are clearly reflected.

To guess the shape of the Earth, there is no need to travel around the world. The impetus for the creation of the Theory of Relativity, which radically transformed our understanding of the world, came from only a few experiments, which also allowed for many different interpretations.

So, precisely because the world is structured like a Holon, this amazing phenomenon of “metaphysical focusing” is possible, when private, seemingly local scientific problems can act as experimentum crucis to choose between various natural philosophical and metaphysical systems.

But it is important to remember something else: you need some special view of the world, a special cognitive optics in order to find these key ones among the piles of unexplained phenomena and contradictory interpretations, focal points.

The world does not appear in every grain of sand taken at random. The ability to find them radically depends on the metaphysics accepted, it would seem, a priori. Psychologists know well that vision is not only a physiological, but also a psychologically determined process. The phenomenon of conceptual blindness, when one cannot see the forest for the trees, is also notorious.

Invaluable (and still unappreciated) merit Lyubishcheva and consists in the fact that he presented the scientific community with a whole cluster of fundamental biological problems, which the vast majority of his colleagues considered either long ago solved or peripheral, of little interest.

And here, first of all, we should remember the famous Lyubishchev triad: system, form, evolution.

How do the problems of systematics (and in particular the question of the principles of constructing the System of living organisms), morphology and the theory of evolution relate? From the point of view of orthodox Darwinism, the answer is extremely simple - this triad of problems itself does not exist. Only the evolutionary problem is real, everything else is just partial, secondary, subordinate to the main and only fundamental one. After all, form and system are only an epiphenomenon of evolution.

Lyubishchev showed that it is precisely conceptual blindness that does not allow his colleagues to see a huge array of data indicating exactly the opposite: form and system have their own immanent logic, irreducible to evolutionary.

This in itself, of course, is an outstanding scientific achievement, but Lyubishchev did much more - he expressed and substantiated in detail a seemingly simple, but as it turned out, extremely deep idea: the answer to the question of how many forms of living things work can serve as the most important, if not a decisive argument in understanding what evolution is. But through the “mechanism” of evolution, the essence of living things is revealed. Are living beings particularly complex automata, or is a fundamentally different—holistic—approach needed to understand life? The answer to this question, central to biology, can be found by reflecting on the problems of systematics.

So, does the multitude of living forms have their own, immanent logic that is not reducible to phylogeny? If not, Darwin and his followers, his philosophical predecessors and teachers are right.

If yes, then there are serious reasons to think that the system of living forms is also objectively exists, how objectively there are, being rooted in the basic laws of nature, many elementary particles, many chemical elements and substances, many crystalline forms.

Then systematics is not at all an auxiliary scientific discipline, as many biologists still believe. Systematics is a manifestation of the fundamental laws of nature, the principles of the structure of the world as a whole, a window into ontology.

7. Discovery of Sergei Meyen

Ideas Lyubishcheva The role of systematics in the correct choice between competing concepts of evolution turned out to be prophetic. This has become clear precisely now, when the community of biologists is gradually beginning to realize the fundamental significance of classical works Sergei Viktorovich Meyen.

So in the twenties of our century Nikolai Ivanovich Vavilov formulated the law of homological series. Despite worldwide recognition, this discovery turned out to be actually a foreign body for modern biology. Even then it was clear that this was a discovery of the extra-class, comparable in significance to the discovery of the periodic table of elements. It immediately caused great excitement among biologists.

No other scientific theory is as controversial as the theory of evolution. According to a recent poll, only 15% of people believe that homo sapiens evolved by chance. Therefore, today, more and more new theories are appearing about how humanity has developed and will develop. In our review of the 10 most popular alternative theories of evolution.

1. Intelligent design

The founders of the intelligent design theory are American mathematician and philosopher Willian Dembski and biochemist Michael Behom. Some things are too complex to evolve by chance, they argue, so instead of assuming that humans are just slightly more advanced apes, we should “start looking for the celestial equivalent of Steve Jobs.” In other words, life on Earth arose as a result of the intervention of someone higher intelligence.

2. Morphic resonance

While much of the world debates evolution in biology, Rupert Sheldrake decided to look at the origin of species from the point of view of the Universe. According to his theory, over time, invisible morphic fields are formed, which contain the collective memory of organisms and substances, including stars and galaxies. This information field influences the subsequent development of similar species.

3.Christian Science

Christian Science is a theory that says that God is everywhere and everything around is a part of Him. This theory, as stated Mary Baker Eddie, based on those contained in Bible eternal truths. This theory also states that nothing exists except the spirit, so everything around is an illusion.

4. Cosmic ancestors

People are used to always thinking that Universe had a specific date of birth. Whether it was created by God or arose as a result of the Big Bang, it happened at some specific moment. The cosmic ancestor theory states that the universe has always existed, and life has also always existed in it. On Earth, life arose by being brought by microbes from space. Life subsequently evolved to imitate life in the Universe.

5. Ancient Astronauts

According to the theory of intelligent design or space legacy, aliens arrived on Earth millions of years ago and specifically created life here. Ancient texts, flying saucers, pyramids, the Mayan calendar, etc. are cited as evidence.

6. Progressive creationism

The well-known story from the book of Genesis is that God created the Earth in six days and rested on the seventh day. Progressive creationists claim that each of these "days" lasted millions of years.

7. Punctuated equilibrium

Of all the theories on this list punctuated equilibrium theory is by far the most mainstream. As is known, all archaeological finds indicate not gradual evolution, but sudden appearance of species. The theory of punctuated equilibrium states that all species exist in stable equilibrium, which is interrupted by short periods of strong change.

8. Theistic evolutionism

Theistic evolutionism is the science that most unites Darwin's theory and God's creation of man. The idea is that God created the Universe and everything in it, only he created everything according to scientific theory. Therefore, evolution is one of the divine instruments in his experiments with creation.

9. Scientology

A religion that was created on the basis of that created by an American science fiction writer Ron Hubbard belief system, claims that human consciousness has gone from birds to sloths, and then to monkeys and finally to people. Humans are the product of an alien race that died in a nuclear disaster millions of years ago, and their consciousness was transferred from one animal to another until it entered the human brain. As a burden of animal memories, feelings such as indecision, envy and toothache remained.

10. Creationism

Creationism claims that everything in the Book of Genesis is absolutely correct. Literally: God created the Earth and everything on it in six days, that we all descended from Noah, and that giants once existed. Besides, the Earth is only six thousand years old, so any geological and archaeological data is complete nonsense.

Whatever theory of the emergence of life on Earth people adhere to still exists today.

Ministry of Education and Science of the Russian Federation

GOU VPO "Kemerovo State University" (KemSU)

Department of Modern Natural Sciences

ABSTRACT

on the topic of:

“Alternative evolutionary theories: Lamarckism, catastrophism,

saltationism.

Synthetic theory of evolution"

Completed: student gr. E-105

Dikazhev Ismail

Checked: K. B. N. Associate Professor

Prokhorova A. M.

Kemerovo 2010

1. Alternative evolutionary theories

Lamarckism

The first holistic doctrine of the evolutionary development of living nature, the main ideas of which were outlined by J. B. Lamarck in “Philosophy of Zoology” (1809).

Lamarckism is based on the idea of gradation - the internal “striving for improvement” inherent in all living things; the action of this factor of evolution determines the development of living nature, the gradual but steady increase in the organization of living beings - from the simplest to the most perfect. The result of gradation is the simultaneous existence in nature of organisms of varying degrees of complexity, as if forming a hierarchical ladder of creatures. The gradation is easily visible when comparing representatives of large systematic categories of organisms (for example, classes) and on organs of primary importance. Considering gradation to be a reflection of the main trend in the development of nature, planted by the “supreme creator of all things,” Lamarck tried to give this process a materialistic interpretation: in a number of cases, he associated the complication of organization with the action of fluids (for example, caloric, electricity) penetrating the body from the external environment. Another factor of evolution, according to Lamarck, is the constant influence of the external environment, leading to a violation of the correct gradation and determining the formation of a whole variety of adaptations of organisms to environmental conditions. Environmental change is the main cause of speciation; as long as the environment is constant, species remain constant; if there is a shift in it, the species change. Lamarck deliberately distinguished between these factors of evolution, noting that the first of them in the body corresponds to “constant abilities”, the second to “abilities subject to change under the influence of circumstances”.

The external environment acts directly on plants and lower animals, lacking a differentiated nervous system, causing adaptive changes in them. Animals with a nervous system experience indirect influence from the environment; their evolutionary transformations are carried out in a more complex way. Any significant change in external conditions leads to a change in the needs of animals living in a given area. Changing needs entails changing habits aimed at satisfying these needs. Changing habits leads to increased use of some organs and lack of use of others. More often, functioning organs strengthen and develop, while those not used weaken and disappear. The resulting functional and morphological changes are passed on to the offspring, intensifying from generation to generation. Thus, according to Lamarck, function plays a leading role in the evolutionary transformations of organisms: a change in form is a consequence of a change in function. The provisions on the exercise and non-exercise of organs and on the inheritance of acquired characteristics were elevated by Lamarck to the rank of universal laws of evolution. The inconsistency of both “laws” was experimentally proven already at the end of the 19th century and especially at the beginning of the 20th century thanks to the discoveries of genetics. In his later works (1815, 1820), Lamarck largely brings together both factors of evolution. He is inclined to consider the environment not only as a force that disrupts the linearity of gradation, but also as the main factor in evolution. Accordingly, he connects the origin of the main branches of the family tree of organisms with the influence of specific conditions of existence.

In justifying his teaching, Lamarck relied on the following facts:

the presence of varieties that occupy an intermediate position between the two species;

difficulties in diagnosing closely related species and the presence of many “doubtful species” in nature;

changes in species forms during the transition to other ecological and geographical conditions;

cases of hybridization, especially interspecific.

Lamarck also considered the discovery of fossil forms, changes in animals during domestication and changes in plants during introduction into culture as important evidence of the transformation of species. Developing ideas about evolution, he came to the conclusion that there are no real boundaries between species and to deny the very existence of species. The observed breaks in the natural series of organic forms (which makes it possible to classify them) are only apparent violations of a single continuous chain of organisms, explained by the incompleteness of our knowledge. Nature, in his opinion, is a continuous series of changing individuals, and taxonomists only artificially, for the sake of convenient classification, divide this series into separate systematic groups. This idea of the fluidity of species forms was in logical connection with the interpretation of development as a process devoid of any interruptions or leaps (the so-called flat evolutionism). This understanding of evolution corresponded to the denial of the natural extinction of species: fossil forms, according to Lamarck, did not become extinct, but, having changed, continue to exist in the guise of modern species. The existence of the lowest organisms, which seems to contradict the idea of gradation, is explained by their constant spontaneous generation from inanimate matter. According to Lamarck, evolutionary changes usually cannot be directly observed in nature only because they occur very slowly and are incommensurate with the relative brevity of human life.

Lamarck extended the principle of evolution to the origin of man, although under the prevailing creationism he was forced to disguise his beliefs. He believed that man descended from monkeys. He considered the transition to upright walking and the emergence of speech to be factors in the development of man. Lamarck also approached historically the highest manifestations of life - the human consciousness and psyche, linking their emergence with the evolution of the nervous system and its highest part - the brain.

Without giving an explanation of organic expediency and without revealing the true cause of evolutionary development, Lamarck for the first time proclaimed the principle of evolution as a universal law of living nature. Having boldly challenged the prevailing ideas about the constancy of species at that time, he was one of the first to make the problem of evolution a subject of special study, a special direction of biological research. This is why Lamarck earned high praise from the classics of Marxism.

Lamarckism did not receive recognition from his contemporaries and after the death of its creator was consigned to oblivion. The revival of Lamarckism in the form of neo-Lamarckism occurred in the last third of the 19th century as a reaction to the spread of Darwinism.

1.2. Catastrophism

The idea of development in the doctrine of catastrophism was concretized in a different way (J. Cuvier, L. Agassiz, A. Sedgwick, W. Bookland, A. Milne-Edwards, R.I. Churchison, R. Owen, etc.). Here the idea of biological evolution acted as a derivative of the more general idea of the development of global geological processes. If Lamarck, with his deistic position, tried to push back the role of divine “creativity”, to fence off the organic world from the interference of the creator, catastrophists, on the contrary, bring God closer to nature, directly introducing into their concept the idea of direct divine intervention in the course of natural processes. Catastrophism is a type of hypothesis of organic evolution in which the progress of organic forms is explained through the recognition of the immutability of individual biological species. This is perhaps the main uniqueness of this concept.

In the system of empirical prerequisites for catastrophism, the following can be indicated:

lack of paleontological connections between historical, successive floras and faunas;

the existence of sharp breaks between adjacent geological layers;

absence of transitional forms between modern and fossil species;

low variability of species throughout the cultural history of mankind;

sustainability, stability of modern species;

the rarity of cases of formation of interspecific hybrids;

detection of extensive lava outpourings;

detection of the replacement of terrestrial sediments by marine sediments and vice versa;

the presence of entire series of overturned strata, the existence of cracks in the strata and deep crustal faults.

The duration of the Earth's existence at the beginning of the 19th century was estimated at about 100 thousand years - such a relatively short period of time is difficult to explain the evolution of organic forms.

The question of the age of the Earth is a special problem. For many centuries, the age of the Earth was considered to be several thousand years, which followed from the biblical myth of the creation of the world. However, by the end of the 18th century, geology was already becoming a real science, and most geologists began to realize that processes such as the formation of sedimentary rocks or weathering are protracted and occur over huge periods of time. In the second half of the 18th century, the age of the Earth was estimated by geologists at only 75 thousand years. However, by the middle of the 19th century, this period of time “stretched” to hundreds of millions of years. Currently, using radioactive dating methods, the age of the Earth is estimated at 4.6 billion years.

The theoretical core of catastrophism was the principle of distinguishing between forces and laws of nature currently operating and those operating in the past. The forces at work in the past are qualitatively different from those at work now. In distant times, powerful, explosive, catastrophic forces acted, interrupting the calm flow of geological and biological processes. The power of these forces is so great that their nature cannot be established by means of scientific analysis. Science cannot judge the causes of these forces, but only their consequences. Thus, catastrophism acts as a phenomenological concept.

The main feature of catastrophism was revealed in the ideas about the suddenness of catastrophes, about the extremely uneven speed of processes of transformation of the Earth's surface, that the history of the Earth is a process of periodic replacement of one type of geological changes by another, and between successive periods there is no natural, successive connection, as there is no it between the factors causing these processes. In relation to organic evolution, these provisions were concretized in two principles:

in principle, fundamental qualitative changes in the organic world as a result of disasters;

in principle, the progressive ascent of organic forms after another catastrophe.

From the point of view of J. Cuvier, those minor changes that took place during the periods between catastrophes could not lead to a qualitative transformation of species. Only during periods of catastrophes, world upheavals, some species of animals and plants disappear and others, qualitatively new ones appear, Cuvier wrote: “Life has more than once shocked our land with terrible events. Countless living beings became victims of catastrophes: some, the inhabitants of the land, were swallowed up by floods, others, who inhabited the depths of the waters, found themselves on land along with the suddenly raised bottom of the sea, their very races disappeared forever, leaving only a few remnants in the world, barely visible to naturalists.” . The creators of the theory of catastrophism proceeded from ideological ideas about the unity of the geological and biological aspects of evolution; consistency of scientific and religious ideas, up to the subordination of the tasks of scientific research to the justification of religious dogmas. Catastrophism is based on the assumption of the existence of leaps and breaks in gradual development.

Is it possible to identify invariant traits in species that replace each other after the next catastrophe? According to Cuvier, the existence of such similarities can be assumed. He identified four main types of animals (vertebrates, soft-bodied, articulated and radiated), in each of which he correlated a certain historically unchanged “composition plan” (the basis for the diversity of systems of correlated characteristics of an organism). The “plan of composition” for catastrophists is an immaterial force, the ideal organizing center of divine creation. In their opinion, the addition of “creative force” after each successive catastrophe determines the progressive ascent of organic forms.

For a long time, the concept of catastrophism in Russian literature was treated condescendingly, as something naive, outdated and completely erroneous. Nevertheless, the significance of this concept in the history of geology, paleontology, and biology is great. Catastrophism contributed to the development of stratigraphy, linking the history of the development of the geological and biological worlds, introducing the idea of uneven rates of transformation of the Earth's surface, highlighting the qualitative uniqueness of certain periods in the history of the Earth, studying the patterns of increasing the level of organization of species within the framework of general aromorphoses, etc. In historical geology and paleontology there is no The very concept of “catastrophe” has also lost its meaning: modern science also does not deny geological disasters. They represent “a natural process that inevitably occurs at a certain stage in the life of a geological system, when quantitative changes go beyond its limits.”

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ABSTRACT

by discipline

"Concepts of modern natural science"

on the topic of:

“Alternative evolutionary theories: Lamarckism, catastrophism,Withaltationism. Synthetic theory of evolution»

1. Alternative evolutionary theories

1.1 Lamarckism

The first holistic doctrine of the evolutionary development of living nature, the main ideas of which were outlined by J.B. Lamarck in Philosophy of Zoology (1809).

Lamarckism is based on the idea of gradation - the internal “striving for improvement” inherent in all living things; the action of this factor of evolution determines the development of living nature, the gradual but steady increase in the organization of living beings - from the simplest to the most perfect. The result of gradation is the simultaneous existence in nature of organisms of varying degrees of complexity, as if forming a hierarchical ladder of creatures. The gradation is easily visible when comparing representatives of large systematic categories of organisms (for example, classes) and on organs of primary importance. Considering gradation to be a reflection of the main trend in the development of nature, planted by the “supreme creator of all things,” Lamarck tried to give this process a materialistic interpretation: in a number of cases, he associated the complication of organization with the action of fluids (for example, caloric, electricity) penetrating the body from the external environment. Another factor of evolution, according to Lamarck, is the constant influence of the external environment, leading to a violation of the correct gradation and determining the formation of a whole variety of adaptations of organisms to environmental conditions. Environmental change is the main cause of speciation; as long as the environment is constant, species remain constant; if there is a shift in it, the species change. Lamarck consciously distinguished between these factors of evolution, noting that the first of them in the body corresponds to “constant abilities”, the second - “abilities subject to change under the influence of circumstances”.

In justifying his teaching, Lamarck relied on the following facts:

The presence of varieties occupying an intermediate position between the two species;

E difficulties in diagnosing closely related species and the presence in nature of many “dubious species”;

І change in species forms during the transition to other ecological and geographical conditions;

E cases of hybridization, especially interspecific.

1.2 Catastrophism

In the system of empirical prerequisites for catastrophism, the following can be indicated:

E lack of paleontological connections between historical, successive floras and faunas;

The existence of sharp breaks between adjacent geological layers;

E lack of transitional forms between modern and fossil species;

E low variability of species throughout the cultural history of mankind;

E stability, stability of modern species;

There are rare cases of formation of interspecific hybrids;

E detection of extensive lava outpourings;

E detection of the replacement of terrestrial sediments by marine sediments and vice versa;

The presence of entire series of inverted layers, the existence of cracks in the layers and deep crustal faults.

The duration of the Earth's existence at the beginning of the 19th century was estimated at approximately 100 thousand years - such a relatively short period of time is difficult to explain the evolution of organic forms.

1) in principle, fundamental qualitative changes in the organic world as a result of disasters;

2) in principle, the progressive ascent of organic forms after the next catastrophe.

1.3 Saltationism

Saltationism- a group of evolutionary theories according to which speciation occurs very quickly - within several generations. The process is associated with the emergence of new individuals, sharply different and reproductively isolated from representatives of the parent species. Saltationism is less developed than the synthetic theory of evolution (STE), but it allows us to explain phenomena with which the latter has difficulties, in particular:

- incompleteness of the fossil record - the absence of continuous series of transitional fossil forms between species and supraspecific taxa;

There is an expected sharp decrease in competition and viability in transitional forms compared to the original species.

Historically, the first scientific ideas similar to saltationism were formulated by Hugo de Vries in 1901. While studying the inheritance of characters in Oenothera Lamarckiana, Hugo de Vries observed the emergence of new forms that were morphologically very different from the parents. Based on the results obtained, he formulated a mutation theory, the main tenet of which was the sudden appearance of new, previously non-existent species during single mutation events. Further studies showed that the selected model object is polymorphic in chromosomal rearrangements and new forms correspond only to new combinations of these rearrangements and are not species.

In the middle of the 20th century, Goldschmidt formulated the idea of systemic mutation - this is a special type of mutation that leads to the appearance of individuals morphologically different from the original forms and which can give rise to new species.

Since the late 1980s, saltationism has been successfully developed by V.N. Quilting. According to V.N. Stegnia, systemic mutations, as a necessary material for evolution, represent stable changes in the orientation of chromosomes in the nuclei of generative and other tissues. Such changes in chromosome orientation alter the regulation of gene activity throughout the genome, leading to physiological changes and reproductive isolation of new forms from the original species.

According to a number of ideas of other supporters of saltationism, systemic mutations are associated with changes in special conservative regions of the genome responsible for the regulation of morphogenesis.

One of the problematic areas in saltation theories is the difficulty of finding sexual partners for individual representatives of a new species, since reproductive isolation with the parent species is formed.

2. Synthetic theory of evolution

2.1 The emergence and development of STE

evolution Lamarckism catastrophism mutation

The synthetic theory in its current form was formed as a result of rethinking a number of provisions of classical Darwinism from the standpoint of genetics of the early 20th century. After the rediscovery of Mendel's laws (in 1901), evidence of the discrete nature of heredity and especially after the creation of theoretical population genetics by the works of R. Fisher (1918-1930), J.B.S. Haldane Jr. (1924), S. Wright (1931; 1932), Darwin’s teachings acquired a solid genetic foundation.

Article by S.S. Chetverikov “On some aspects of the evolutionary process from the point of view of modern genetics” (1926) essentially became the core of the future synthetic theory of evolution and the basis for the further synthesis of Darwinism and genetics. In this article, Chetverikov showed the compatibility of the principles of genetics with the theory of natural selection and laid the foundations of evolutionary genetics. The main evolutionary publication of S.S. Chetverikova was translated into English in the laboratory of J. Haldane, but was never published abroad. In the works of J. Haldane, N.V. Timofeev-Resovsky and F.G. Dobzhansky ideas expressed by S.S. Chetverikov, spread to the West, where almost simultaneously R. Fischer expressed very similar views on the evolution of dominance.

The impetus for the development of the synthetic theory was given by the hypothesis of the recessivity of new genes. In the language of genetics of the second half of the twentieth century, this hypothesis assumed that in each reproducing group of organisms, during the maturation of gametes, mutations - new gene variants - constantly arise as a result of errors during DNA replication.

The influence of genes on the structure and functions of the body is pleiotropic: each gene is involved in determining several traits. On the other hand, each trait depends on many genes; geneticists call this phenomenon genetic polymerization of traits. Fisher says that pleiotropy and polymery reflect the interaction of genes, due to which the external manifestation of each gene depends on its genetic environment. Therefore, recombination, generating more and more new gene combinations, ultimately creates for a given mutation such a gene environment that allows the mutation to manifest itself in the phenotype of the carrier individual. Thus, the mutation falls under the influence of natural selection, selection destroys combinations of genes that make it difficult for organisms to live and reproduce in a given environment, and preserves neutral and beneficial combinations that are subject to further reproduction, recombination and testing by selection. Moreover, first of all, such gene combinations are selected that contribute to the favorable and at the same time stable phenotypic expression of initially little noticeable mutations, due to which these mutant genes gradually become dominant. This idea was expressed in the work of R. Fisher “The genetic theory of natural selection” (1930). Thus, the essence of the synthetic theory is the preferential reproduction of certain genotypes and their transmission to descendants. In the question of the source of genetic diversity, the synthetic theory recognizes the main role of gene recombination.

It is believed that an evolutionary act took place when selection preserved a gene combination that was atypical for the previous history of the species. As a result, evolution requires the presence of three processes:

1) mutational, generating new gene variants with low phenotypic expression;

2) recombination, creating new phenotypes of individuals;

3) breeding, which determines the correspondence of these phenotypes to given living or growing conditions.

All supporters of the synthetic theory recognize the participation of the three listed factors in the evolution.

An important prerequisite for the emergence of a new theory of evolution was the book of the English geneticist, mathematician and biochemist J.B.S. Haldane Jr., who published it in 1932 under the title “The causes of evolution.” Haldane, creating the genetics of individual development, immediately included the new science in solving the problems of macroevolution.

Major evolutionary innovations very often arise on the basis of neoteny (preservation of juvenile characteristics in an adult organism). Neoteny Haldane explained the origin of man (“naked ape”), the evolution of such large taxa as graptolites and foraminifera. In 1933, Chetverikova’s teacher N.K. Koltsov showed that neoteny is widespread in the animal kingdom and plays an important role in progressive evolution. It leads to morphological simplification, but at the same time the richness of the genotype is preserved.

1937 was named year of origin of STE- this year a book by the Russian-American geneticist and entomologist-systematist F.G. Dobzhansky "Genetics and the Origin of Species". The success of Dobzhansky's book was determined by the fact that he was both a naturalist and an experimental geneticist. “Dobzhansky’s double specialization allowed him to be the first to build a solid bridge from the camp of experimental biologists to the camp of naturalists” (E. Mayr). For the first time, the most important concept of “isolating mechanisms of evolution” was formulated - those reproductive barriers that separate the gene pool of one species from the gene pools of other species. Dobzhansky introduced the half-forgotten Hardy-Weinberg equation into wide scientific circulation. He also introduced the “S. Wright effect” into naturalistic material, believing that microgeographic races arise in an adaptively neutral way.

In American literature, among the creators of STE, the names of F. Dobzhansky, J. Huxley, E. Mayr, B. Rensch, J. Stebbins are most often mentioned. This is, of course, not a complete list. Only among Russian scientists, at least, one should name I.I. Shmalhausen, N.V. Timofeev-Resovsky, G.F. Gause, N.P. Dubinina, A.L. Takhtajyan. Of the British scientists, the great role is played by J.B.S. Haldane Jr., D. Lack, K. Waddington, G. de Beer. Among the active creators of STE, German historians name the names of E. Baur, W. Zimmermann, W. Ludwig, G. Heberer and others.

2.2 Basic provisions of STE, their historical formation and development

In 1930-1940 a broad synthesis of genetics and Darwinism quickly occurred. Genetic ideas penetrated taxonomy, paleontology, embryology, and biogeography. The term “modern” or “evolutionary synthesis” comes from the title of J. Huxley’s book “Evolution: The Modern synthesis” (1942). The expression "synthetic theory of evolution" in precise application to this theory was first used by J. Simpson in 1949.

· the local population is considered the elementary unit of evolution;

· the material for evolution is mutation and recombination variability;

· natural selection is considered as the main reason for the development of adaptations, speciation and the origin of supraspecific taxa;

· genetic drift and the founder principle are the reasons for the formation of neutral traits;

· a species is a system of populations reproductively isolated from populations of other species, and each species is ecologically isolated;

· Speciation consists of the emergence of genetic isolating mechanisms and occurs primarily under conditions of geographic isolation.

Thus, the synthetic theory of evolution can be characterized as a theory of organic evolution through natural selection of genetically determined traits.

The activity of the American creators of STE was so high that they quickly created the International Society for the Study of Evolution, which in 1946 became the founder of the journal Evolution. The American Naturalist magazine has returned to publishing works on evolutionary topics, emphasizing a synthesis of genetics, experimental and field biology. As a result of numerous and varied studies, the main provisions of STE were not only successfully tested, but also modified and supplemented with new ideas.

In 1942, the German-American ornithologist and zoogeographer E. Mayr published the book “Systematics and the Origin of Species,” in which the concept of a polytypic species and a genetic-geographical model of speciation were consistently developed. Mayr proposed the founder's principle, which was formulated in its final form in 1954. If genetic drift, as a rule, provides a causal explanation for the formation of neutral traits in the temporal dimension, then the founder's principle in the spatial dimension.

After the publication of the works of Dobzhansky and Mayr, taxonomists received a genetic explanation for what they had long believed: subspecies and closely related species differ in adaptively neutral characters.

None of the works on STE can compare with the mentioned book by the English experimental biologist and naturalist J. Huxley “Evolution: The Modern synthesis” (1942). Huxley's work surpasses even Darwin's own book in terms of the volume of analyzed material and breadth of problems. Huxley kept all directions in the development of evolutionary thought in mind for many years, closely followed the development of related sciences, and had personal experience as an experimental geneticist. Prominent historian of biology Provine assessed Huxley’s work as follows: “Evolution. A Modern Synthesis" was the most comprehensive on the topic and documents than other works on the topic. The books of Haldane and Dobzhansky were written primarily for geneticists, Mayr for taxonomists, and Simpson for paleontologists. Huxley's book became the dominant force in the evolutionary synthesis."

In terms of volume, Huxley's book had no equal (645 pages). But the most interesting thing is that all the main ideas presented in the book were very clearly written out by Huxley on 20 pages back in 1936, when he sent an address to the British Association for the Advancement of Science entitled “Natural selection and evolutionary progress”. In this aspect, none of the publications on evolutionary theory published in the 1930s and 40s can compare with Huxley's article. Well aware of the spirit of the times, Huxley wrote: “Biology is currently in a phase of synthesis. Until this time, the new disciplines had worked in isolation. There has now been a tendency towards unification, which is more fruitful than the old one-sided views of evolution" (1936). Even in the works of the 1920s, Huxley showed that the inheritance of acquired characteristics is impossible; natural selection acts as a factor of evolution and as a factor of stabilization of populations and species (evolutionary stasis); natural selection acts on small and large mutations; Geographic isolation is the most important condition for speciation. The apparent purpose in evolution is explained by mutations and natural selection.

The main points of Huxley's 1936 article can be summarized very briefly in this form:

1. Mutations and natural selection are complementary processes that individually are not capable of creating directed evolutionary changes.

2. Selection in natural populations most often acts not on individual genes, but on gene complexes. Mutations may not be beneficial or harmful, but their selective value varies in different environments. The mechanism of action of selection depends on the external and genotypic environment, and the vector of its action depends on the phenotypic manifestation of mutations.

3. Reproductive isolation is the main criterion indicating the completion of speciation. Speciation can be continuous and linear, continuous and divergent, abrupt and convergent.

4. Gradualism and pan-adaptationism are not universal characteristics of the evolutionary process. Most land plants are characterized by discontinuity and sudden formation of new species. Widespread species evolve gradually, while small isolates evolve discontinuously and not always adaptively. Discontinuous speciation is based on specific genetic mechanisms (hybridization, polyploidy, chromosomal aberrations). Species and supraspecific taxa, as a rule, differ in adaptive-neutral characters. The main directions of the evolutionary process (progress, specialization) are a compromise between adaptability and neutrality.

5. Potentially preadaptive mutations are widespread in natural populations. This type of mutation plays a critical role in macroevolution, especially during periods of sudden environmental changes.

6. The concept of gene action rates explains the evolutionary role of heterochrony and allometry. Synthesizing the problems of genetics with the concept of recapitulation leads to an explanation of the rapid evolution of species at dead ends of specialization. Through neoteny, a “rejuvenation” of the taxon occurs, and it acquires new rates of evolution. Analysis of the relationship between onto- and phylogeny makes it possible to detect epigenetic mechanisms of the direction of evolution.

7. In the process of progressive evolution, selection acts in the direction of improving organization. The main result of evolution was the appearance of man. With the emergence of man, the great biological evolution develops into a psychosocial one. Evolutionary theory is one of the sciences that studies the formation and development of human society. It creates the foundation for understanding human nature and his future.

A broad synthesis of data from comparative anatomy, embryology, biogeography, paleontology with the principles of genetics was carried out in the works of I.I. Schmalhausen (1939), A.L. Takhtadzhyan (1943), J. Simpson (1944), B. Rensch (1947). From these studies grew the theory of macroevolution. Only Simpson's book was published in English and during the period of widespread expansion of American biology, it is most often mentioned among the seminal works.

I.I. Shmalhausen was a student of A.N. Severtsov, however, already in the 20s his independent path was determined. He studied quantitative patterns of growth, the genetics of the manifestation of traits, and genetics itself. Schmalhausen was one of the first to carry out a synthesis of genetics and Darwinism. From the enormous heritage of I.I. Schmalhausen's monograph “Paths and Patterns of the Evolutionary Process” (1939) stands out. For the first time in the history of science, he formulated the principle of unity of the mechanisms of micro- and macroevolution. This thesis was not simply postulated, but directly followed from his theory of stabilizing selection, which includes population genetic and macroevolutionary components (ontogenesis autonomization) in the course of progressive evolution.

A.L. Takhdadzhyan in the monographic article: “Relationships of ontogeny and phylogeny in higher plants” (1943) not only actively included botany in the orbit of evolutionary synthesis, but actually built an original ontogenetic model of macroevolution (“soft saltationism”). Takhtadzhyan’s model based on botanical material developed many of A.N.’s remarkable ideas. Severtsov, especially the theory of archallaxis (a sharp, sudden change in an organ at the earliest stages of its morphogenesis, leading to changes in the entire course of ontogenesis). The most difficult problem of macroevolution - gaps between large taxa - was explained by Takhtadzhyan by the role of neoteny in their origin. Neoteny played an important role in the origin of many higher taxonomic groups, including flowering ones. Herbaceous plants evolved from woody plants through layered neoteny.

Back in 1931, S. Wright proposed the concept of random genetic drift, which speaks of the absolutely random formation of the gene pool of a deme as a small sample from the gene pool of the entire population. Initially, genetic drift turned out to be the very argument that was missing for a very long time in order to explain the origin of non-adaptive differences between taxa. Therefore, the idea of drift immediately became close to a wide range of biologists. J. Huxley called drift the “Wright effect” and considered it “the most important recent taxonomic discovery.” George Simpson (1948) based his hypothesis of quantum evolution on drift, according to which a population cannot independently move out of the zone of attraction of an adaptive peak. Therefore, in order to get into an unstable intermediate state, a random genetic event independent of selection is necessary - genetic drift. However, enthusiasm for genetic drift soon waned. The reason is intuitively clear: any completely random event is unique and unverifiable. The widespread citation of S. Wright's works in modern evolutionary textbooks, which present an exclusively synthetic concept, cannot be explained otherwise than by the desire to highlight the diversity of views on evolution, ignoring the kinship and differences between these views.

The ecology of populations and communities entered evolutionary theory through the synthesis of Gause's law and the genetic-geographical model of speciation. Reproductive isolation has been complemented by ecological niche as the most important criterion for a species. At the same time, the niche approach to species and speciation turned out to be more general than a purely genetic one, since it is also applicable to species that do not have a sexual process.

The entry of ecology into the evolutionary synthesis represented the final stage in the formation of the theory. From that moment on, the period of using STE in the practice of taxonomy, genetics, and selection began, which continued until the development of molecular biology and biochemical genetics.

With the development of new sciences, STE began to expand and modify again. Perhaps the most important contribution of molecular genetics to the theory of evolution was the division of genes into regulatory and structural (model of R. Britten and E. Davidson, 1971). It is the regulatory genes that control the emergence of reproductive isolating mechanisms, which change independently of enzyme genes and cause rapid changes (on a geological time scale) at the morphological and physiological levels.

The idea of random changes in gene frequencies has found application in the theory of neutrality (Kimura, 1985), which goes far beyond the traditional synthetic theory, being created on the foundation not of classical, but of molecular genetics. Neutrality is based on a completely natural position: not all mutations (changes in the nucleotide sequence of DNA) lead to a change in the sequence of amino acids in the corresponding protein molecule. Those amino acid substitutions that have taken place do not necessarily cause a change in the shape of the protein molecule, and when such a change does occur, it does not necessarily change the nature of the protein's activity. Consequently, many mutant genes perform the same functions as normal genes, which is why selection behaves completely neutrally towards them. For this reason, the disappearance and consolidation of mutations in the gene pool depend purely on chance: most of them disappear soon after their appearance, a minority remains and can exist for quite a long time. As a result, the selection that evaluates phenotypes is “essentially indifferent to what genetic mechanisms determine the development of a given form and corresponding function; the nature of molecular evolution is completely different from the nature of phenotypic evolution” (Kimura, 1985).

The last statement, reflecting the essence of neutralism, is in no way consistent with the ideology of the synthetic theory of evolution, which goes back to the concept of germ plasm by A. Weisman, with which the development of the corpuscular theory of heredity began. According to Weisman's views, all factors of development and growth are found in germ cells; Accordingly, in order to change the organism, it is necessary and sufficient to change the germ plasm, that is, the genes. As a result, the theory of neutrality inherits the concept of genetic drift, generated by neo-Darwinism, but subsequently abandoned by it.

Some inconsistency within the theory itself most likely suggests that the development of STE will continue with the advent of new discoveries in the field of evolution.

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