Evolutionary theory. History of development, modern concept, development prospects. Theories of evolution Describe the theory of evolution

Term evolution(Latin evolutio - deployment) is widely used in various fields of science: the evolution of the Earth, society, methods of cognition. Biological evolution is the irreversible, directed historical development of living nature, accompanied by changes in the genetic composition of populations, the formation of adaptations in organisms, the formation and extinction of species, the transformation of biogeocenoses and the biosphere as a whole. Evolutionary theory is the doctrine of the general patterns and driving forces of the historical development of living nature. The purpose of this teaching is to identify the patterns of development of the organic world for the subsequent management of this process. Evolutionary teaching solves the problem of understanding the general laws of evolution, the causes and mechanisms of transformation of living things at all levels of its organization: molecular, subcellular, cellular, organ, organismal, population, biogeocenotic, biospheric.

In the history of the development of the theory of evolution, several stages can be distinguished:
1. Pre-Darwinian period (until the middle of the 19th century): works of K. Linnaeus, Lamarck, Roulier, etc.
2. Darwinian period (2nd half of the 19th century - 20s of the 20th century): the formation of classical Darwinism and the main anti-Darwinian trends in evolutionary thought.
3. The crisis of classical Darwinism (20s - 30s of the XX century), associated with the emergence of genetics and the transition to population thinking.
4. Formation and development of the synthetic theory of evolution (30s - 50s of the XX century).
5. Attempts to create a modern theory of evolution (60s - 90s of the XX century).

The origin of the idea of ​​the development of living things dates back to the heyday of the philosophical thought of the Ancient East and Ancient Greece. By the second half of the 19th century, enormous factual material on botany, zoology, and anatomy had been accumulated. Ideas about the variability of species appeared, which were supported by the rapid development of agriculture, the development of new breeds and varieties. A great contribution to the development of biology was made by C. Linnaeus, who proposed a system of classification of animals and plants using subordinate taxonomic groups. He introduced binary nomenclature (double species name). In 1808, in the work “Philosophy of Zoology” J.B. Lamarck raises the question of the causes and mechanisms of evolutionary transformations and sets forth the first theory of evolution. Lamarck's evolutionary theory, the creation of cell theory, data from comparative anatomy, systematics, paleontology and embryology prepared the basis for the creation of the doctrine of the evolution of the organic world. This doctrine, which is the largest generalization of natural science of the 19th century, was created by Charles Darwin (1809-1882). In 1859, Charles Darwin published his main work, “The Origin of Species by Means of Natural Selection,” in which, using a wealth of factual material, he showed the patterns of evolution of organisms and the animal origin of humans.

The first to introduce students to the content of Darwin’s teachings was Professor of St. Petersburg University S.S. Kutorg (lecture in 1860).

The main provisions of Darwin's theory:

1. Heredity and variability are the properties of organisms on which evolution is based. Charles Darwin distinguished the following forms of variability: definite (according to modern concepts, non-hereditary or modification variability) and indefinite (hereditary) variability. He attached leading importance to the latter for evolution.
2. Natural selection is the driving, directing factor of evolution. C. Darwin came to the conclusion that it is inevitable in nature that the selective destruction of less adapted individuals and the reproduction of others. Natural selection in nature is carried out through the struggle for existence. C. Darwin distinguished between intraspecific, interspecific and struggle with factors of inanimate nature.
3. Based on ideas about the origin of modern species through natural selection, the theory of evolution solves the problem of expediency and fitness in nature. Adaptation is always relative. According to Charles Darwin, the evolving unit is the species.
4. The diversity of species is considered as a result of natural selection and the associated divergence (divergence) of characters.

Schematically, the essence of Charles Darwin's theory can be depicted as follows: the struggle for existence - natural selection - speciation. Charles Darwin's theory has stood the test of time. Darwinism is a theory of evolution of the organic world, based on the recognition of natural selection as the main driving force in the development of living nature. Evolutionary theory is constantly evolving.

To explain the mechanisms of evolution at the first stages of development of the theory, there was not enough knowledge of genetic patterns. Genetics as a science arose in 1900. At this time, G. de Vries (Holland) proposed the mutation theory of evolution, according to which species are formed suddenly, as a result of mutations. At the same time, the role of natural selection as a factor of evolution was denied. However, evidence gradually accumulated indicating that genes change under the influence of the environment. In 1926, the work of S.S. appeared. Chetverikov “On some aspects of the evolutionary process from the point of view of modern genetics”, which gave rise to the synthesis of genetics and classical Darwinism. Subsequent works by N.P. Dubinina, N.V. Timofeev-Resovsky, F.G. Dobzhansky et al. showed that in evolution, not only the appearance of new mutations plays an important role, but also a change in the frequency of gene occurrence, which is determined by natural selection. As a result of using the achievements of genetics to analyze natural selection, the doctrine of micro- and macroevolution arose. Microevolution is changes occurring in a population (observed in nature and reproduced in experiment). Microevolution is associated with changes in structural genes. Macroevolution is processes occurring in systematic units that are above the species: the evolution of genera, families, orders, classes (they are judged by indirect data). Macroevolution is associated with changes in regulatory genes.

Basic provisions of the synthetic theory of evolution:
1. The unit of evolution is a population, not a species, as Charles Darwin believed.
2. Elementary evolutionary material - mutations. They can accumulate in the general gene pool of the population, creating a huge reserve of genetic potential of the population.
3. An elementary evolutionary phenomenon is a change in the phenotypic composition of a population based on changes in the gene pool.
4. Elementary factors of evolution - mutation process, natural selection, isolation, waves of life, genetic drift, i.e. random change in the genetic composition of a population.

Population- an elementary unit of evolution. A population is a collection of individuals of a certain species that inhabit a certain space for a long time, separated from other populations by isolation. All individuals of the population interbreed freely with each other (panmixia), producing fertile offspring. The population has morphophysiological, ecological and genetic characteristics.

The morphophysiological characteristic consists of the sum of the morphological and physiological characteristics of all individuals of the population. The ecological characteristics of the population include its size, the size of the occupied territory, age and sex composition. Genetic characteristics include the gene pool, reaction rate, genetic heterogeneity and genetic unity of the population, its polymorphism. The population is also characterized by the frequency of occurrence of genes and genotypes.

From the standpoint of the synthetic theory of evolution, an elementary evolutionary phenomenon is a long-term directed change in the phenotypic composition of a population based on changes in its gene pool. It arises under the influence of elementary evolutionary factors. The most important of them are: mutation process, population waves, natural selection, isolation.

In 1859, the work of the English naturalist Charles Darwin, “The Origin of Species,” was published. Since then, evolutionary theory has been key in explaining the laws of development of the organic world. It is taught in schools in biology classes, and even some churches have recognized its validity.

What is Darwin's theory?

Darwin's theory of evolution is the concept that all organisms are descended from a common ancestor. She emphasizes the naturalistic origin of life with change. Complex creatures evolve from simpler ones, this takes time. Random mutations occur in the genetic code of the body; beneficial mutations are retained, helping to survive. Over time they accumulate, and the result is a different species, not just a variation of the original, but a completely new creature.

Basic principles of Darwin's theory

Darwin's theory about the origin of man is included in the general theory about the evolutionary development of living nature. Darwin believed that Homo Sapiens evolved from an inferior form of life and shared a common ancestor with the ape. The same laws that gave rise to other organisms led to its appearance. The evolutionary concept is based on the following principles:

1. Overproduction. Species populations remain stable because a small proportion of the offspring survive and reproduce.
2. Fight for survival. Children of every generation must compete to survive.
3. Device. Adaptation is an inherited trait that increases the likelihood of surviving and reproducing in a particular environment.
4. Natural selection. The environment "selects" living organisms with more suitable traits. The offspring inherits the best, and the species is improved for a specific habitat.
5. Speciation. Over generations, beneficial mutations gradually increase, and bad ones disappear. Over time, the accumulated changes become so great that a new species results.

Darwin's theory - fact or fiction?

Darwin's theory of evolution has been the subject of much debate for many centuries. On the one hand, scientists can tell what ancient whales were like, but on the other hand, they lack fossil evidence. Creationists (adherents of the divine origin of the world) take this as proof that evolution did not happen. They scoff at the idea that a land whale ever existed.

Ambulocetus

Evidence for Darwin's theory

To the delight of Darwinians, in 1994 paleontologists found the fossil remains of Ambulocetus, a walking whale. Its webbed front paws helped it move on land, and its powerful hind paws and tail helped it swim deftly. In recent years, more and more remains of transitional species, the so-called “missing links,” have been found. Thus, Charles Darwin's theory about the origin of man was supported by the discovery of the remains of Pithecanthropus, an intermediate species between ape and man. In addition to paleontological evidence, there is other evidence of evolutionary theory:

1. Morphological– according to Darwinian theory, each new organism is not created by nature from scratch, everything comes from a common ancestor. For example, the similar structure of the paws of a mole and the wings of a bat is not explained in terms of utility; they probably received it from a common ancestor. This also includes five-fingered limbs, similar oral structures in different insects, atavisms, rudiments (organs that have lost their significance in the process of evolution).
2. Embryological– all vertebrates exhibit a great similarity in embryos. A human baby that has been in the womb for one month has gill sacs. This indicates that the ancestors were aquatic inhabitants.
3. Molecular genetic and biochemical– unity of life at the level of biochemistry. If all organisms did not descend from one ancestor, they would have their own genetic code, but the DNA of all creatures consists of 4 nucleotides, and there are over 100 of them in nature.

Refutation of Darwin's theory

Darwin's theory is unprovable - this alone is enough for critics to question its entire validity. No one has ever observed macroevolution - seen how one species transformed into another. And in general, when will at least one monkey turn into a human? This question is asked by all those who doubt the correctness of Darwin's arguments.

Facts refuting Darwin's theory:

1. Research has shown that planet Earth is approximately 20-30 thousand years old. This has been recently discussed by many geologists who study the amount of cosmic dust on our planet and the age of rivers and mountains. Darwinian evolution took billions of years.
2. Humans have 46 chromosomes, and apes have 48. This does not fit into the idea that humans and apes had a common ancestor. Having “lost” the chromosomes along the way from the ape, the species could not evolve into a reasonable one. Over the past few thousand years, not a single whale has come onto land, and not a single monkey has turned into a human.
3. Natural beauty, which, for example, anti-Darwinists include a peacock's tail, has nothing to do with usefulness. If there were evolution, the world would be inhabited by monsters.

Darwin's theory and modern science

Darwin's theory of evolution came to light when scientists still knew nothing about genes. Darwin observed the pattern of evolution but was unaware of the mechanism. At the beginning of the 20th century, genetics began to develop - chromosomes and genes were discovered, and later the DNA molecule was deciphered. For some scientists, Darwin's theory has been refuted - the structure of organisms turned out to be more complex, and the number of chromosomes in humans and monkeys is different.

But supporters of Darwinism claim that Darwin never said that man descended from apes - they have a common ancestor. The discovery of genes for Darwinists gave impetus to the development of the synthetic theory of evolution (the inclusion of genetics in Darwin's theory). The physical and behavioral changes that make natural selection possible occur at the level of DNA and genes. Such changes are called mutations. Mutations are the raw material on which evolution operates.

Darwin's theory - interesting facts

Charles Darwin's theory of evolution is the work of a man who, having abandoned the profession of a doctor because of, went to study theology. A few more interesting facts:

1. The phrase “survival of the fittest” belongs to Darwin’s contemporary and like-minded person, Herbert Spencer.
2. Charles Darwin not only studied exotic animal species, but also dined on them.
3. The Anglican Church has officially apologized to the author of the theory of evolution, albeit 126 years after his death.

Darwin's theory and Christianity

At first glance, the essence of Darwin's theory contradicts the divine universe. At one time, the religious environment was hostile to new ideas. Darwin himself ceased to be a believer during his work. But now many representatives of Christianity have come to the conclusion that there can be real reconciliation - there are those who have religious beliefs and do not deny evolution. The Catholic and Anglican churches accepted Darwin's theory, explaining that God, as the creator, gave impetus to the beginning of life, and then it developed naturally. The Orthodox wing is still unfriendly to Darwinists.

Anaximander. We know about Anaximander’s scheme from the historian of the 1st century BC. e. Diodorus Siculus. In his account, when the young Earth was illuminated by the Sun, its surface first hardened and then fermented, and rot arose, covered with thin shells. In these shells all kinds of animal breeds were born. Man supposedly arose from a fish or a fish-like animal. Despite the originality, Anaximander's reasoning is purely speculative and not supported by observations. Another ancient thinker, Xenophanes, paid more attention to observations. So, he identified the fossils that he found in the mountains with the imprints of ancient plants and animals: laurel, mollusk shells, fish, seals. From this he concluded that the land once sank into the sea, bringing death to land animals and people, and turned into mud, and when it rose, the prints dried up. Heraclitus, despite his metaphysics being imbued with the idea of ​​constant development and eternal formation, did not create any evolutionary concepts. Although some authors still attribute him to the first evolutionists.

The only author in whom one can find the idea of ​​gradual change in organisms was Plato. In his dialogue "The State" he put forward the infamous proposal: improving the breed of people by selecting the best representatives. Without a doubt, this proposal was based on the well-known fact of selection of sires in animal husbandry. In the modern era, the unfounded application of these ideas to human society developed into the doctrine of eugenics, which underpinned the racial policies of the Third Reich.

Middle Ages and Renaissance

With the rise of scientific knowledge after the “Dark Ages” of the early Middle Ages, evolutionary ideas again begin to creep into the works of scientists, theologians and philosophers. Albertus Magnus was the first to note the spontaneous variability of plants, leading to the emergence of new species. Examples once given by Theophrastus he characterized as transmutation one type to another. The term itself was apparently taken by him from alchemy. In the 16th century, fossil organisms were rediscovered, but only towards the end of the 17th century the idea that this was not a “play of nature”, not stones in the shape of bones or shells, but the remains of ancient animals and plants, finally took hold of minds. In his work of the year, “Noah’s Ark, Its Shape and Capacity,” Johann Buteo cited calculations that showed that the ark could not contain all the species of known animals. In the year Bernard Palissy organized an exhibition of fossils in Paris, where he for the first time compared them with living ones. In the year he published in print the idea that since everything in nature is “in eternal transmutation,” many fossil remains of fish and shellfish belong to extinct species

Evolutionary ideas of the New Age

As we see, things did not go further than expressing scattered ideas about the variability of species. The same trend continued with the advent of modern times. So Francis Bacon, politician and philosopher, suggested that species can change by accumulating “errors of nature.” This thesis again, as in the case of Empedocles, echoes the principle of natural selection, but there is no word yet about a general theory. Oddly enough, the first book on evolution can be considered a treatise by Matthew Hale. Matthew Hale) "The Primitive Origin of Mankind Considered and Examined According to the Light of Nature." This may seem strange already because Hale himself was not a naturalist or even a philosopher, he was a lawyer, theologian and financier, and he wrote his treatise during a forced vacation on his estate. In it, he wrote that one should not assume that all species were created in their modern form; on the contrary, only archetypes were created, and all the diversity of life developed from them under the influence of numerous circumstances. Hale also foreshadows many of the controversies about randomness that arose after the establishment of Darwinism. In the same treatise, the term “evolution” in the biological sense was first mentioned.

Ideas of limited evolutionism like Hale's arose constantly, and can be found in the writings of John Ray, Robert Hooke, Gottfried Leibniz, and even in the later work of Carl Linnaeus. They are expressed more clearly by Georges Louis Buffon. Observing the deposition of sediments from water, he came to the conclusion that the 6 thousand years allotted for the history of the Earth by natural theology were not enough for the formation of sedimentary rocks. The age of the Earth calculated by Buffon was 75 thousand years. Describing the species of animals and plants, Buffon noted that, along with useful characteristics, they also have those to which it is impossible to attribute any usefulness. This again contradicted natural theology, which asserted that every hair on the body of an animal was created for the benefit of it or man. Buffon came to the conclusion that this contradiction can be eliminated by accepting the creation of only a general plan, which varies in specific incarnations. Applying Leibniz's “law of continuity” to systematics, he spoke out against the existence of discrete species in 2010, considering species to be the fruit of the imagination of taxonomists (in this one can see the origins of his ongoing polemics with Linnaeus and the antipathy of these scientists towards each other).

Lamarck's theory

A step towards combining the transformist and systematic approaches was made by the natural scientist and philosopher Jean Baptiste Lamarck. As a proponent of species change and a deist, he recognized the Creator and believed that the Supreme Creator created only matter and nature; all other inanimate and living objects arose from matter under the influence of nature. Lamarck emphasized that “all living bodies come from one another, and not through sequential development from previous embryos.” Thus, he opposed the concept of preformationism as autogenetic, and his follower Etienne Geoffroy Saint-Hilaire (1772-1844) defended the idea of ​​​​the unity of the structural plan of animals of various types. Lamarck’s evolutionary ideas are most fully presented in “Philosophy of Zoology” (1809), although Lamarck formulated many of the provisions of his evolutionary theory in introductory lectures to a zoology course back in 1800-1802. Lamarck believed that the stages of evolution do not lie on a straight line, as followed from the “ladder of creatures” by the Swiss natural philosopher C. Bonnet, but have many branches and deviations at the level of species and genera. This introduction set the stage for future “family trees.” Lamarck also proposed the term “biology” in its modern sense. However, the zoological works of Lamarck - the creator of the first evolutionary doctrine - contained many factual inaccuracies and speculative constructions, which is especially evident when comparing his works with the works of his contemporary, rival and critic, the creator of comparative anatomy and paleontology, Georges Cuvier (1769-1832). Lamarck believed that the driving factor of evolution could be the “exercise” or “non-exercise” of organs, depending on the adequate direct influence of the environment. Some naivety of the argumentation of Lamarck and Saint-Hilaire largely contributed to the anti-evolutionary reaction to transformism of the early 19th century, and provoked absolutely factual criticism from the creationist Georges Cuvier and his school.

Catastrophism and transformism

Cuvier's ideal was Linnaeus. Cuvier divided animals into four “branches,” each of which is characterized by a common structural plan. For these “branches,” his follower A. Blainville proposed the concept of type, which fully corresponded to Cuvier’s “branches.” A phylum is not simply the highest taxon in the animal kingdom. There are not and cannot be transitional forms between the four identified types of animals. All animals belonging to the same type are characterized by a common structure plan. This most important position of Cuvier is extremely significant even today. Although the number of types has significantly exceeded the number 4, all biologists speaking about type proceed from a fundamental idea that gives much concern to the promoters of gradualism in evolution - the idea of ​​​​the isolation of the structural plans of each type. Cuvier fully accepted the Linnaean hierarchy of the system and built his system in the form of a branching tree. But this was not a family tree, but a tree of similarities between organisms. As rightly noted by A.A. Borisyak, “having built a system on ... a comprehensive account of the similarities and differences of organisms, he thereby opened the door to the evolutionary doctrine that he fought against.” Cuvier's system was apparently the first system of organic nature in which modern forms were considered side by side with fossils. Cuvier is rightfully considered a significant figure in the development of paleontology, biostratigraphy and historical geology as sciences. The theoretical basis for identifying the boundaries between layers was Cuvier’s idea of ​​catastrophic extinctions of faunas and floras at the boundaries of periods and eras. He also developed the doctrine of correlations (italics by N.N. Vorontsov), thanks to which he restored the appearance of the skull as a whole, the skeleton as a whole, and, finally, provided a reconstruction of the external appearance of a fossil animal. Together with Cuvier, his French colleague paleontologist and geologist A. Brongniard (1770-1847) made his contribution to stratigraphy, and, independently of them, the English surveyor and mining engineer William Smith (1769-1839). The term for the study of the form of organisms - morphology - was introduced into biological science by Goethe, and the doctrine itself arose at the end of the 18th century. For creationists of that time, the concept of unity of body plan meant a search for similarity, but not relatedness, of organisms. The task of comparative anatomy was seen as an attempt to understand by what plan the Supreme Being created all the diversity of animals that we observe on Earth. Evolutionary classics call this period in the development of biology “idealistic morphology.” This direction was also developed by the opponent of transformism, the English anatomist and paleontologist Richard Owen (1804-1892). By the way, it was he who proposed, in relation to structures that perform similar functions, to apply the now well-known analogy or homology, depending on whether the animals being compared belong to the same structural plan or to different ones (to the same type of animal or to different types).

Evolutionists - Darwin's contemporaries

In 1831, the English forester Patrick Matthew (1790-1874) published the monograph “Ship logging and tree planting.” The phenomenon of uneven growth of trees of the same age, the selective death of some and the survival of others has long been known to foresters. Matthew suggested that selection not only ensures the survival of the fittest trees, but can also lead to changes in species during historical development. Thus, the struggle for existence and natural selection were known to him. At the same time, he believed that the acceleration of the evolutionary process depends on the will of the organism (Lamarckism). For Matthew, the principle of the struggle for existence coexisted with the recognition of the existence of catastrophes: after upheavals, a few primitive forms survive; in the absence of competition after the revolution, the evolutionary process proceeds at a high pace. Matthew's evolutionary ideas went unnoticed for three decades. But in 1868, after the publication of On the Origin of Species, he republished his evolutionary pages. After this, Darwin familiarized himself with the works of his predecessor and noted Matthew’s achievements in the historical review of the 3rd edition of his work.

Charles Lyell (1797-1875) was a major figure of his time. He brought back to life the concept of actualism (“Fundamentals of Geology”, 1830-1833), coming from ancient authors, as well as from such significant personalities in human history as Leonardo da Vinci (1452-1519), Lomonosov (1711-1765), James Hutton (England, Hutton, 1726-1797) and, finally, Lamarck. Lyell's acceptance of the concept of knowledge of the past through the study of modernity meant the creation of the first holistic theory of the evolution of the face of the Earth. The English philosopher and historian of science William Whewell (1794-1866) in 1832 put forward the term uniformitarianism in relation to the assessment of Lyell's theory. Lyell spoke about the invariability of the action of geological factors over time. Uniformitarianism was the complete antithesis of Cuvier's catastrophism. “The teaching of Lyell now prevails as much,” wrote the anthropologist and evolutionist I. Ranke, “as the teaching of Cuvier once dominated. At the same time, it is often forgotten that the doctrine of catastrophes could hardly have provided a satisfactory schematic explanation of geological facts for so long in the eyes of the best researchers and thinkers if it had not been based on a certain amount of positive observations. The truth here also lies between the extremes of theory.” As modern biologists admit, “Cuvier’s catastrophism was a necessary stage in the development of historical geology and paleontology. Without catastrophism, the development of biostratigraphy would hardly have progressed so quickly.”

Scotsman Robert Chambers (1802-1871), a book publisher and popularizer of science, published in London “Traces of the Natural History of Creation” (1844), in which he anonymously promoted the ideas of Lamarck, spoke about the duration of the evolutionary process and about evolutionary development from simply organized ancestors to more complex forms . The book was designed for a wide readership and over 10 years went through 10 editions with a circulation of at least 15 thousand copies (which in itself is impressive for that time). Controversy has flared up around a book by an anonymous author. Always very reserved and cautious, Darwin stood aloof from the debate that was unfolding in England, but carefully observed how criticism of particular inaccuracies turned into criticism of the very idea of ​​mutability of species, so as not to repeat such mistakes. Chambers, after the publication of Darwin's book, immediately joined the ranks of supporters of the new teaching.

In the 20th century, people remembered Edward Blyth (1810-1873), an English zoologist and researcher of the fauna of Australia. In 1835 and 1837 he published two articles in the English Journal of Natural History in which he said that in conditions of fierce competition and lack of resources, only the strongest have a chance of leaving offspring.

Thus, even before the publication of the famous work, the entire course of development of natural science had already prepared the ground for the acceptance of the doctrine of the variability of species and selection.

Darwin's works

A new stage in the development of evolutionary theory came in 1859 as a result of the publication of Charles Darwin's seminal work, “The Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life.” The main driving force of evolution according to Darwin is natural selection. Selection, acting on individuals, allows those organisms that are better adapted for life in a given environment to survive and leave offspring. The action of selection causes species to break apart into subspecies, which in turn diverge over time into genera, families, and all larger taxa.

With his characteristic honesty, Darwin pointed to those who directly pushed him to write and publish the doctrine of evolution (apparently, Darwin was not too interested in the history of science, since in the first edition of The Origin of Species he did not mention his immediate predecessors: Wells, Matthew, Blyte). Darwin was directly influenced in the process of creating the work by Lyell and to a lesser extent by Thomas Malthus (1766-1834), with his geometric progression of numbers from the demographic work “Essay on the Law of Population” (1798). And, one might say, Darwin was “forced” to publish his work by the young English zoologist and biogeographer Alfred Wallace (1823-1913) by sending him a manuscript in which, independently of Darwin, he sets out the ideas of the theory of natural selection. At the same time, Wallace knew that Darwin was working on the doctrine of evolution, for the latter himself wrote to him about this in a letter dated May 1, 1857: “This summer will mark 20 years (!) since I started my first notebook on the question of about how and in what ways species and varieties differ from each other. Now I am preparing my work for publication... but I do not intend to publish it earlier than in two years... Really, it is impossible (within the framework of a letter) to expound my views on the causes and methods of changes in the state of nature; but step by step I came to a clear and distinct idea - whether true or false, this must be judged by others; for - alas! – the most unshakable confidence of the author of the theory that he is right is in no way a guarantee of its truth!” Darwin's common sense is evident here, as well as the gentlemanly attitude of the two scientists towards each other, which is clearly visible when analyzing the correspondence between them. Darwin, having received the article on June 18, 1858, wanted to submit it for publication, keeping silent about his work, and only at the insistence of his friends he wrote a “short extract” from his work and presented these two works to the Linnean Society.

Darwin fully adopted the idea of ​​gradual development from Lyell and, one might say, was a uniformitarian. The question may arise: if everything was known before Darwin, then what is his merit, why did his work cause such a resonance? But Darwin did what his predecessors could not do. Firstly, he gave his work a very relevant title, which was “on everyone’s lips.” The public had a burning interest specifically in “The Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life.” It is difficult to remember another book in the history of world natural science, the title of which would so clearly reflect its essence. Perhaps Darwin came across the title pages or titles of the works of his predecessors, but simply did not have the desire to familiarize himself with them. We can only wonder how the public would react if Matthew had released his evolutionary views under the title “The Possibility of Variation of Plant Species Over Time through Survival (Selection) of the Fittest.” But, as we know, “Ship’s timber…” did not attract attention.

Secondly, and this is the most important thing, Darwin was able to explain to his contemporaries the reasons for the variability of species based on his observations. He rejected, as untenable, the idea of ​​“exercising” or “non-exercising” organs and turned to the facts of the breeding of new breeds of animals and varieties of plants by people - to artificial selection. He showed that indefinite variability of organisms (mutations) are inherited and can become the beginning of a new breed or variety, if it is useful to humans. Having transferred these data to wild species, Darwin noted that only those changes that are beneficial to the species for successful competition with others can be preserved in nature, and spoke about the struggle for existence and natural selection, to which he attributed an important, but not the only role as the driver of evolution. Darwin not only gave theoretical calculations of natural selection, but also showed, using factual material, the evolution of species in space, with geographic isolation (finches) and explained the mechanisms of divergent evolution from the standpoint of strict logic. He also introduced the public to the fossil forms of giant sloths and armadillos, which could be seen as evolution through time. Darwin also allowed for the possibility of long-term preservation of a certain average norm of a species in the process of evolution by eliminating any deviating variants (for example, sparrows that survived a storm had an average wing length), which was later called stasygenesis. Darwin was able to prove to everyone the reality of the variability of species in nature, therefore, thanks to his work, ideas about the strict constancy of species came to naught. It was pointless for staticists and fixists to continue to persist in their positions.

Development of Darwin's ideas

As a true gradualist, Darwin was concerned that the lack of transitional forms would be the downfall of his theory, and attributed this lack to the incompleteness of the geological record. Darwin was also concerned about the “dissolution” of a newly acquired trait over a series of generations, with subsequent crossing with ordinary, unchanged individuals. He wrote that this objection, along with breaks in the geological record, is one of the most serious for his theory.

Darwin and his contemporaries did not know that in 1865, the Austro-Czech naturalist Abbot Gregor Mendel (1822-1884) discovered the laws of heredity, according to which a hereditary trait does not “dissolve” in a series of generations, but passes (in the case of recessivity) into a heterozygous state and can be propagated in a population environment.

Such scientists as the American botanist Asa Gray (1810-1888) begin to speak out in support of Darwin; Alfred Wallace, Thomas Henry Huxley (Huxley; 1825-1895) - in England; classic of comparative anatomy Karl Gegenbaur (1826-1903), Ernst Haeckel (1834-1919), zoologist Fritz Müller (1821-1897) - in Germany. No less distinguished scientists criticize Darwin's ideas: Darwin's teacher, professor of geology Adam Sedgwick (1785-1873), the famous paleontologist Richard Owen, the prominent zoologist, paleontologist and geologist Louis Agassiz (1807-1873), the German professor Heinrich Georg Bronn (1800-1873). 1862).

An interesting fact is that it was Bronn who translated Darwin’s book into German, who did not share his views, but believed that the new idea had a right to exist (the modern evolutionist and popularizer N.N. Vorontsov gives Bronn credit for this as a true scientist). Considering the views of another opponent of Darwin, Agassiz, we note that this scientist spoke about the importance of combining the methods of embryology, anatomy and paleontology to determine the position of a species or other taxon in the classification scheme. Thus, the species receives its place in the natural order of the universe. It was interesting to learn that an ardent supporter of Darwin, Haeckel, widely promoted the triad postulated by Agassiz, the “method of triple parallelism” already applied to the idea of ​​kinship, and it, fueled by Haeckel’s personal enthusiasm, captivated his contemporaries. All any serious zoologists, anatomists, embryologists, paleontologists begin to build entire forests of phylogenetic trees. With the light hand of Haeckel, the idea of ​​monophyly - descent from one ancestor, which reigned supreme over the minds of scientists in the middle of the 20th century, is spread as the only possible idea. Modern evolutionists, based on the study of the method of reproduction of Rhodophycea algae, which is different from all other eukaryotes (immobile both male and female gametes, the absence of a cell center and any flagellated formations), speak of at least two independently formed ancestors of plants. At the same time, they found out that “The emergence of the mitotic apparatus occurred independently at least twice: in the ancestors of the kingdoms of fungi and animals, on the one hand, and in the subkingdoms of true algae (except Rhodophycea) and higher plants, on the other” (exact quote, p. 319) . Thus, the origin of life is recognized not from one ancestral organism, but from at least three. In any case, it is noted that “no other scheme, like the proposed one, can turn out to be monophyletic” (ibid.). Scientists were also led to polyphyly (origin from several unrelated organisms) by the theory of symbiogenesis, which explains the appearance of lichens (a combination of algae and fungus) (p. 318). And this is the most important achievement of the theory. In addition, recent research suggests that more and more examples are being found showing “the prevalence of paraphyly in the origin of relatively closely related taxa.” For example, in the “subfamily of African tree mice Dendromurinae: the genus Deomys is molecularly close to the true mice Murinae, and the genus Steatomys is close in DNA structure to the giant mice of the subfamily Cricetomyinae. At the same time, the morphological similarity of Deomys and Steatomys is undeniable, which indicates the paraphylitic origin of Dendromurinae.” Therefore, the phylogenetic classification needs to be revised, based not only on external similarity, but also on the structure of the genetic material (p. 376). The experimental biologist and theorist August Weismann (1834-1914) spoke in a fairly clear manner about the cell nucleus as the carrier of heredity. Independently of Mendel, he came to the most important conclusion about the discreteness of hereditary units. Mendel was so ahead of his time that his work remained virtually unknown for 35 years. Weismann's ideas (sometime after 1863) became the property of wide circles of biologists and a subject for discussion. The most fascinating pages of the origin of the doctrine of chromosomes, the emergence of cytogenetics, the creation of T.G. Morgan's chromosome theory of heredity in 1912-1916. – all this was greatly stimulated by August Weismann. Studying the embryonic development of sea urchins, he proposed to distinguish between two forms of cell division - equatorial and reduction, i.e. approached the discovery of meiosis, the most important stage of combinative variability and the sexual process. But Weisman could not avoid some speculativeness in his ideas about the mechanism of transmission of heredity. He thought that only the so-called cells have the entire set of discrete factors - “determinants”. "germinal tract". Some determinants enter some of the cells of the “soma” (body), others – others. Differences in the sets of determinants explain the specialization of soma cells. So, we see that, having correctly predicted the existence of meiosis, Weisman was mistaken in predicting the fate of gene distribution. He also extended the principle of selection to competition between cells, and, since cells are carriers of certain determinants, he spoke of their struggle among themselves. The most modern concepts of “selfish DNA”, “selfish gene”, developed at the turn of the 70s and 80s. XX century have much in common with Weismann's competition of determinants. Weisman emphasized that the “germ plasm” is isolated from the soma cells of the whole organism, and therefore spoke about the impossibility of inheriting characteristics acquired by the organism (soma) under the influence of the environment. But many Darwinists accepted this idea of ​​Lamarck. Weisman's harsh criticism of this concept caused a negative attitude towards him and his theory personally, and then towards the study of chromosomes in general, on the part of orthodox Darwinists (those who recognized selection as the only factor of evolution).

The rediscovery of Mendel's laws occurred in 1900 in three different countries: Holland (Hugo de Vries 1848-1935), Germany (Karl Erich Correns 1864-1933) and Austria (Erich von Tschermak 1871-1962), which simultaneously discovered Mendel's forgotten work. In 1902, Walter Sutton (Seton, 1876-1916) gave a cytological basis for Mendelism: diploid and haploid sets, homologous chromosomes, the process of conjugation during meiosis, prediction of the linkage of genes located on the same chromosome, the concept of dominance and recessivity, as well as allelic genes - all this was demonstrated on cytological preparations, was based on precise calculations of Mendeleev's algebra and was very different from hypothetical family trees, from the style of naturalistic Darwinism of the 19th century. The mutation theory of de Vries (1901-1903) was not accepted not only by the conservatism of orthodox Darwinists, but also by the fact that in other plant species researchers were unable to obtain the wide range of variability he achieved with Oenothera lamarkiana (it is now known that evening primrose is a polymorphic species , having chromosomal translocations, some of which are heterozygous, while homozygotes are lethal. De Vries chose a very successful object for obtaining mutations and at the same time not entirely successful, since in his case it was necessary to extend the results achieved to other plant species). De Vries and his Russian predecessor, the botanist Sergei Ivanovich Korzhinsky (1861-1900), who wrote in 1899 (St. Petersburg) about sudden spasmodic “heterogeneous” deviations, thought that the possibility of macromutations rejected Darwin’s theory. At the dawn of genetics, many concepts were expressed according to which evolution did not depend on the external environment. The Dutch botanist Jan Paulus Lotsi (1867-1931), who wrote the book “Evolution by Hybridization,” where he rightly drew attention to the role of hybridization in speciation in plants, also came under criticism from Darwinists.

If in the middle of the 18th century the contradiction between transformism (continuous change) and the discreteness of taxonomic units of systematics seemed insurmountable, then in the 19th century it was thought that gradualistic trees built on the basis of kinship came into conflict with the discreteness of hereditary material. Evolution through visually discernible large mutations could not be accepted by Darwinian gradualism.

Confidence in mutations and their role in the formation of species variability was restored by Thomas Ghent Morgan (1886-1945), when this American embryologist and zoologist moved on to genetic research in 1910 and, ultimately, chose the famous Drosophila. Probably, we should not be surprised that 20-30 years after the events described, it was population geneticists who came to evolution not through macromutations (which began to be recognized as unlikely), but through a steady and gradual change in the frequencies of allelic genes in populations. Since macroevolution by that time seemed to be an indisputable continuation of the studied phenomena of microevolution, gradualism began to seem an inseparable feature of the evolutionary process. There was a return to Leibniz’s “law of continuity” at a new level, and in the first half of the 20th century a synthesis of evolution and genetics was able to occur. Once again, once opposing concepts came together. (names, conclusions of evolutionists and chronology of events are taken from Nikolai Nikolaevich Vorontsov, “Development of evolutionary ideas in biology, 1999)

Let us recall that in the light of the latest biological ideas put forward from the position of materialism, now there is again a movement away from the law of continuity, now not by geneticists, but by evolutionists themselves. The famous S.J. Gould raised the question of punctualism (punctuated equilibrium), as opposed to generally accepted gradualism, so that it became possible to explain the reasons for the already obvious picture of the absence of transitional forms among the fossil remains, i.e. the impossibility of building a truly continuous line of kinship from origins to the present. There is always a gap in the geological record.

Modern theories of biological evolution

Synthetic theory of evolution

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 (-), J. B. S. Haldane Jr. (), S. Wright ( ; ), the teaching Darwin acquired a solid genetic foundation.

Neutral theory of molecular evolution

The theory of neutral evolution does not dispute the decisive role of natural selection in the development of life on Earth. The discussion is about the proportion of mutations that have adaptive significance. Most biologists accept a number of results from the theory of neutral evolution, although they do not share some of the strong claims originally made by M. Kimura.

Epigenetic theory of evolution

The main provisions of the epigenetic theory of evolution were formulated in the 20th year by M. A. Shishkin based on the ideas of I. I. Shmalhausen and K. H. Waddington. The theory considers a holistic phenotype as the main substrate of natural selection, and selection not only fixes useful changes, but also takes part in their creation. The fundamental influence on heredity is not the genome, but the epigenetic system (ES) - a set of factors affecting ontogenesis. The general organization of the ES is transmitted from ancestors to descendants, which shapes the organism during its individual development, and selection leads to the stabilization of a number of successive ontogenies, eliminating deviations from the norm (morphoses) and forming a stable development trajectory (creod). Evolution according to ETE consists in the transformation of one creed into another under the disturbing influence of the environment. In response to disturbance, the ES is destabilized, as a result of which the development of organisms along deviating paths of development becomes possible, and multiple morphoses arise. Some of these morphoses receive a selective advantage, and over subsequent generations their ES develops a new stable development trajectory and a new creed is formed.

Ecosystem theory of evolution

This term is understood as a system of ideas and approaches to the study of evolution, focusing on the features and patterns of evolution of ecosystems at various levels - biocenoses, biomes and the biosphere as a whole, and not taxa (species, families, classes, etc.). The provisions of the ecosystem theory of evolution are based on two postulates:

• Naturalness and discreteness of ecosystems. An ecosystem is a really existing (and not allocated for the convenience of the researcher) object, which is a system of interacting biological and non-biological (eg soil, water) objects, territorially and functionally separated from other similar objects. The boundaries between ecosystems are clear enough to allow us to talk about the independent evolution of neighboring objects.
• The determining role of ecosystem interactions in determining the rate and direction of population evolution. Evolution is seen as a process of creating and filling ecological niches or licenses.

The ecosystem theory of evolution operates with such terms as coherent and incoherent evolution, ecosystem crises at various levels. The modern ecosystem theory of evolution is based mainly on the works of Soviet and Russian evolutionists: V. A. Krasilov, S. M. Razumovsky, A. G. Ponomarenko, V. V. Zherikhin and others.

Evolutionary doctrine and religion

Although in modern biology many unclear questions remain about the mechanisms of evolution, the vast majority of biologists do not doubt the existence of biological evolution as a phenomenon. However, some believers of a number of religions find some provisions of evolutionary biology contrary to their religious beliefs, in particular, the dogma of the creation of the world by God. In this regard, in part of society, almost from the moment of the birth of evolutionary biology, there has been a certain opposition to this teaching from the religious side (see creationism), which in some times and in some countries has reached the point of criminal sanctions for teaching evolutionary teaching (which became the reason, for example, for the scandalous famous "monkey process" in the USA in the city).

It should be noted that the accusations of atheism and denial of religion, brought by some opponents of the teaching of evolution, are based to a certain extent on a misunderstanding of the nature of scientific knowledge: in science, no theory, including the theory of biological evolution, can either confirm or deny the existence of such subjects from the other world, like God (if only because God could use evolution in the creation of living nature, as the theological doctrine of “theistic evolution” states).

On the other hand, the theory of evolution, being a scientific theory, considers the biological world as part of the material world and relies on its natural and self-sufficient, i.e., natural origin, alien, therefore, to any otherworldly or divine intervention; alien for the reason that the growth of scientific knowledge, penetrating into previously incomprehensible and explainable only by the activity of otherworldly forces, seems to take away the ground from religion (when explaining the essence of the phenomenon, the need for a religious explanation disappears, because there is a convincing natural explanation). In this regard, evolutionary teaching may be aimed at denying the existence of extranatural forces, or rather their interference in the process of development of the living world, which is one way or another assumed by religious systems.

Attempts to contrast evolutionary biology with religious anthropology are also mistaken. From the point of view of scientific methodology, a popular thesis “man came from apes” is only an excessive simplification (see reductionism) of one of the conclusions of evolutionary biology (about the place of man as a biological species on the phylogenetic tree of living nature), if only because the concept “man” is polysemantic: man as a subject of physical anthropology is by no means identical to man as a subject of philosophical anthropology, and it is incorrect to reduce philosophical anthropology to physical anthropology.

Many believers of different religions do not find the teaching of evolution to be contrary to their faith. The theory of biological evolution (along with many other sciences - from astrophysics to geology and radiochemistry) contradicts only the literal reading of sacred texts telling about the creation of the world, and for some believers this is the reason for rejecting almost all the conclusions of natural sciences that study the past of the material world (literalist creationism ).

Among believers who profess the doctrine of literalist creationism, there are a number of scientists who are trying to find scientific evidence for their doctrine (so-called “scientific creationism”). However, the scientific community disputes the validity of this evidence.

Literature

• Berg L.S. Nomogenesis, or Evolution based on patterns. - Petersburg: State Publishing House, 1922. - 306 p.
• Kordyum V. A. Evolution and the biosphere. - K.: Naukova Dumka, 1982. - 264 p.
• Krasilov V. A. Unsolved problems of the theory of evolution. - Vladivostok: Far Eastern Scientific Center of the USSR Academy of Sciences, 1986. - P. 140.
• Lima de Faria A. Evolution without selection: Autoevolution of form and function: Trans. from English. - M.: Mir, 1991. - P. 455.
• Nazarov V. I. Evolution not according to Darwin: Changing the evolutionary model. Tutorial. Ed. 2nd, rev. - M.: LKI Publishing House, 2007. - 520 p.
• Tchaikovsky Yu. V. The science of life development. Experience of the theory of evolution. - M.: Partnership of Scientific Publications KMK, 2006. - 712 p.
• Golubovsky M. D. Non-canonical hereditary changes // Nature. - 2001. - No. 8. - P. 3–9.
• Meyen S.V. The path to a new synthesis, or where do homological series lead? // Knowledge is power. - 1972. - № 8.

Scientists have always been concerned with the question of not only the origin of existing organisms, but also the mechanisms of these changes.

Accordingly, each scientist put forward his own hypotheses and tried to substantiate them.

We will look at the evolutionary theories of the most famous scientists.

Carl Linnaeus

A Swiss scientist and a very religious man, Linnaeus was a naturalist who studied botany and zoology, and evolutionary theory was not the main goal of his research.

He introduced his taxonomy of organisms (taxonomic categories), a binary nomenclature for describing living things. The species was considered the basic unit of taxonomy.

As for evolution, Linnaeus was a creationist, i.e. believed that all living things were created by God and species do not change.

Jean Baptiste Lamarck

The first scientist who tried to build a holistic theory of evolution.

“all living things are characterized by a “striving for perfection”…” J.B. Lamarck

Firstly, he read that living things came from non-living things, and secondly, the division of animals into vertebrates and invertebrates was his merit. He rejected the concept of “species”, believing that the unit of evolutionary change is the organism itself - the individual.

Lamarck spoke about variability as the main mechanism for adaptation, adaptation to changing conditions, that newly acquired characteristics must necessarily be inherited, but he considered the basis of the mechanisms of all this to be “the internal desire for perfection and exercise.”

Charles Darwin

Everyone knows about him. His portraits are in all schools, there are museums named after him all over the world. He is constantly credited with the origin of man from the monkey, although he DIDN’T write about it!

We are interested in the main points of his theory of biological evolution, on which he worked for 20 years!

The basis for the evolution of all living things is variability;

Traits that help an organism survive in changing conditions must be inherited;

The driving force of evolution is the struggle for existence;

Survival and preferential reproduction of the fit - natural selection;

Natural selection leads to divergence of characters and, ultimately, to speciation.”

Modern (synthetic theory of evolution)

The scientist who “synthesized” (hence the name) combined Darwin’s theory and genetics - S.S. Chetveryakov.

The basis of evolution is mutations, and specifically genetic ones, because they must be inherited;

As in the classical theory, in the synthetic theory of evolution the main driving factor is natural selection;

The elementary unit of evolution is a population;

Evolution is a long process - the change of one population after another leads, ultimately, to the formation of a species or several species (divergence);

A species is a closed formation, with gene flow observed - individuals migrate from one population to another;

Macroevolution is the result of microevolution, while all the patterns of microevolution (at the species level) move to a higher level.

Examples of tasks.

A1. Name the scientist who first attempted to classify living beings and proposed a convenient and simple principle of double names for each species.

1) J. B. Lamarck;
2) J. Cuvier;
3) K. Linnaeus;
4) C. Darwin.

AT 12. Establish a correspondence between scientists and views on the historical development of living nature.

A) the driving force of evolution is the internal desire for perfection

B) changes in environmental conditions cause positive, negative and neutral hereditary changes in organisms

B) acquired characteristics are inherited

D) the driving force of evolution is natural selection E) the elementary evolutionary unit is the individual E) the elementary evolutionary unit is the population

1) C. Darwin

2) J. B. Lamarck

B - 2 (note: according to Lamarck - precisely acquired ones, according to Darwin - all)

E - 1 (Darwin has this type, there is a slight inaccuracy here, but in most Unified State Exam questions this is also the case)

The idea of ​​the development of living nature - the idea of ​​evolution - can be traced in the works of ancient materialists in India, China, Mesopotamia, Egypt, and Greece. At the beginning of the 1st millennium BC. e. In India, there were philosophical schools that defended the ideas of the development of the material world (including the organic) from “primordial matter.” Even more ancient texts of the Ayur-Veda claim that man descended from monkeys who lived about 18 million years ago (when translated into modern chronology on the continent that united Hindustan and southeast Asia. About 4 million years ago, the ancestors of modern people, supposedly switched to collective food acquisition, which gave them the opportunity to stock up. Modern man, according to these ideas, appeared a little less than 1 million years ago. Of course, these were only brilliant guesses based on excellent knowledge of the anatomy of humans and animals.

In China 2 thousand years BC. e. selection of cattle, horses and ornamental plants was carried out. At the end of the 1st millennium BC. e. there was a classification of plants (stone fruits, legumes, succulents, creeping plants, shrubs, etc.). At the same time, teachings about the possibility of transforming some living beings into others during the process of evolution were widespread in China. The close ties of the countries of the Ancient World made this knowledge the property of philosophers in the Mediterranean countries, where it was further developed. In Aristotle (IV century BC) we already encounter a coherent system of views on the development of living nature, based on an analysis of the general plan of the structure of higher animals, homology and correlation of organs. Aristotle's fundamental works “On the Parts of Animals”, “History of Animals”, “On the Origin of Animals” had a great influence on the subsequent development of biology.

However, despite the external similarity of the ancient and our ideas, the views of the ancient thinkers had the character of abstract speculative doctrines.

Decline of knowledge in the Middle Ages.

After almost two thousand years of development of knowledge in the Ancient World - China, India, Egypt, Greece - the dark Middle Ages, the “dark night for natural science,” began in Europe for many centuries. People were burned at the stake not only for expressing the idea of ​​​​the development of nature, but also for reading the books of ancient naturalists and philosophers. The forced introduction of faith into science turns the latter into an appendage of religion.

Church teachings allotted about 6 thousand years for the entire development of the world; for centuries it has been preserved as the official point of view about the creation of the world by the Lord God in 4004 BC. e. The study of nature was effectively prohibited; hundreds of talented scientists, thousands and thousands of ancient books were destroyed during this time. In Spain alone, about 35 thousand people were burned at the stake of the Inquisition and more than 300 thousand were tortured. The last official fire of the Inquisition burned in 1826. Of course, during these years there was an accumulation of natural science knowledge (in monasteries and universities).

The spread of the ideas of evolutionism during the Renaissance and Enlightenment.

The Middle Ages are replaced by the Renaissance (XV-XVI centuries). With its onset, the works of ancient naturalists began to spread again. The books of Aristotle and other ancient authors come to European countries from North Africa and Spain in translations from Arabic. As a result of the development of trade and navigation, knowledge about the diversity of the organic world is rapidly growing, and an inventory of flora and fauna is taking place. In the 16th century the first multi-volume descriptions of the animal and plant world appear, anatomy achieves brilliant successes, in the 17th century. W. Harvey creates the doctrine of blood circulation, and R. Hooke, M. Malpighi and others lay the foundations of microscopy and the study of the cellular structure of organisms. Growing natural science knowledge needed systematization and generalization. The first stage of the process of systematization of biological knowledge ends in the 18th century. the works of the great Swedish naturalist C. Linnaeus (1707-1778).

The ideas of evolution are beginning to be seen more and more clearly in the works of naturalists and philosophers. Even G. Leibniz (1646-1716) proclaimed the principle of gradation of living beings and predicted the existence of transitional forms between plants and animals. The principle of gradation was further developed in the idea of ​​a “ladder of creatures,” which for some became an expression of ideal continuity in structure, and for others - proof of the transformation, evolution of living nature. In 1749, the multi-volume “Natural History” by J. Buffon began to be published, in which he substantiates the hypothesis about the past development of the Earth. In his opinion, it covers 80-90 thousand years, but only in recent periods have living organisms appeared on Earth from inorganic substances: first plants, then animals and humans. J. Buffon saw evidence of unity of origin in terms of the structure of animals and explained the similarity of close forms by their origin from common ancestors.

The idea of ​​evolution is also embedded in the works of the encyclopedist D. Diderot (1713-1784): minor changes in all creatures and the length of time the Earth existed can explain the emergence of diversity in the organic world. P. Maupertuis (1698-1759) expressed brilliant guesses about the corpuscular nature of heredity, the evolutionary role of the destruction of forms not adapted to existence, and the significance of isolation in the development of new forms. C. Darwin's grandfather E. Darwin (1731 -1802) in poetic form affirms the principle of the unity of origin of all living beings and indicates that the organic world has developed over millions of years. In the last years of his life, K. Linnaeus also came to accept evolution, believing that close species within the genus developed naturally, without the participation of divine power.

In the second half of the 18th century. The Age of Enlightenment reaches Russia: in one form or another, evolutionary views are characteristic of such naturalists as M.V. Lomonosov, K.F. Wolf, P.S. Pallas, A.N. Radishchev. M.V. Lomonosov in his treatise “On the Layers of the Earth” (1763) wrote: “... in vain many people think that everything as we see was first created by the creator...”.

Characterizing the development of evolutionary thought in this era, we can say that at this time there was an intensive accumulation of natural scientific material. The most insightful researchers are trying to move from a simple description of the material available in nature to an explanation of the emergence of various forms. In the 18th century There is an ever-increasing struggle between the old ideas of creationism (as the concept of the creation of the world) and new - evolutionary ideas.