Evolutionary teaching is the sum of all ideas about the patterns and mechanisms of changes occurring in organic nature. According to him, all existing organisms descended from their distant “relatives” through long-term changes. It analyzes how individual organisms develop (ontogenesis), and considers the development paths of entire groups of organisms (phylogeny) and their adaptation.

The doctrine of evolution goes back to ancient times, where naturalists and Rome (Aristotle, Democritus, Anaxagoras...) expressed their assumptions about the development and transformations of organisms. However, these conclusions were not based on scientific knowledge and were purely guesswork. In the Middle Ages, there was stagnation in the development of this teaching. This was due to the dominance of religious dogma and scholasticism. Thus, in the Christian world, the creationist point of view was in the lead for a long time. Despite this, some scientists expressed their opinion about the existence of monsters, which was confirmed by the finds of fossil remains.

In the process of accumulating facts, a new direction appeared in the 18th century - transformism, within which the variability of species was studied. Representatives of the doctrine were such scientists as J. Buffoni, E. Darwin, E. Geoffroy Saint-Hilhervaux. Their evolutionary doctrine had two facts in the form of evidence: the presence of transitional interspecific forms, the similarity of the structure of animals and plants in the same group. However, none of these figures spoke about the reasons for the changes taking place.

And only in 1809 did Lamarck’s evolutionary doctrine appear, which was

Reflected in the book “Philosophy of Zoology”. Here, for the first time, the question of the reasons for changes in species was raised. He believed that due to the changing environment, the species themselves were changing. Moreover, he introduced gradations, i.e. transitions from lower forms to higher ones. This evolutionary development, according to Lamarck, is inherent in all living things and comes from the desire for perfection.

Observations of the natural world led him to two main principles, which are reflected in the law of “non-exercise - exercise.” According to him, organs develop as they are used, after which “inheritance of favorable properties” occurs, i.e. favorable traits were passed on from generation to generation and later either their development continued or they disappeared. However, Lamarck’s work was not appreciated in the scientific world until Charles Darwin’s book “On the Origin of Species” was published. The arguments in favor of it made it very popular. However, this scientist was also a supporter of the heritability of acquired traits. However, the contradictions discovered were so serious that they contributed to the revival of Lamarckism as neo-Lamarckism.

After a long time, research by biologists led to the emergence of a synthetic evolutionary doctrine. (STE). It does not have a clear date of origin or a specific author and is a collective work of scientists. Despite the fact that the authors had a lot of differences in their views, some provisions were not in doubt: represented by a local population; the material for evolutionary development is recombination and mutational variability; the main reason for the development of adaptations is natural selection; neutral signs are formed thanks to some other provisions.

Currently, a large number of scientists use the concept of “modern evolutionary theory”. It does not require the presence of one, and at the same time its main achievement is the fact that saltation changes alternate with gradual ones.

In his presentation, when the young Earth was illuminated by the Sun, its surface first hardened, and then fermented, and rot appeared, 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. That 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. The same treatise first mentions the term “evolution” in the biological sense.

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 precipitation of 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. Buffon's calculated age of the Earth was 75 thousand years. Describing the species of animals and plants, Buffon noticed 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 1996, 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 animal structure plan 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 beings” 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 early XIX c, and provoked absolutely factual criticism from the creationist Georges Cuvier and his school.

Catastrophism and transformism

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: Wallace, 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 it will be 20 years (!) since I started my first notebook on the question of how and in what way 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 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, prominent zoologist, paleontologist and geologist Louis Agassiz (1807-1873), German professor Heinrich Georg Bronn (1800-1873). 1862).

An interesting fact is that Darwin’s book was translated into German by Bronn, who did not share his views, but believed that new idea has a right to exist (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 being 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 and 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, it was found 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.” 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). 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.

The experimental biologist and theorist August Weismann (1834-1914) spoke in a fairly clear manner about the cell nucleus as a 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 by T. G. Morgan of the chromosomal theory of heredity in 1912-1916. - all this was greatly stimulated by August Weismann. Exploring embryonic development sea ​​urchins, he proposed to distinguish between two forms of cell division - equatorial and reduction, that is, he 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), who 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 Mendelian 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 , which has 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.

In the light of the latest biological ideas, there is a movement away from the law of continuity, now not by geneticists, but by evolutionists themselves. So the famous evolutionist S.J. Gould raised the issue of punctualism (punctuated equilibrium) as opposed to gradualism.

Modern theories of biological 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. The theory of neutral evolution explains the processes of molecular evolution of living organisms at levels no higher than organismal ones. But it is not suitable for explaining synthetic evolution for mathematical reasons. Based on statistics for evolution, mutations can either occur randomly, causing adaptations, or those changes that occur gradually. The theory of neutral evolution does not contradict the theory of natural selection; it only explains the mechanisms occurring at the cellular, supracellular and organ levels.

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).

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.

Some 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.

Recognition of Evolution by the Catholic Church

Literature

• Vorontsov N. N. Development of evolutionary ideas in biology - M.: Progress-Tradition, 1999. - 640 p.
• Experts from the US National Academy of Sciences and the American Institute of Medicine. Origin of life. Science and faith = Science, Evolution, and Creationism - M.: Astrel, 2010. - 96 p. - .

see also

Links

• Official website of the State Darwin Museum
• N. N. Vorontsov. Ernst Haeckel and the fate of Darwin's teachings
• Article by V.P. Shcherbakov “Evolution as resistance to entropy” on elementy.ru
• “What is evolution like?” (article about symbiosis and gene exchange)
• A. S. Rautian. Can distant species exchange properties? (“Permissiveness” of viral gene transfer and its limitations)
• A. N. Gorban, R. G. Grain production. DARWIN'S DEMON. The idea of ​​optimality and natural selection M.: Nauka (chief editor of physical and mathematical literature), 1988
• G. F. Gause. Struggle for existence.
• Lev Vygotsky, Alexander Luria. “Sketches on the history of behavior: Monkey. Primitive. Child"
• Free access to illustrations from the book by N. H. Barton, D. E. G. Briggs, J. A. Eisen "Evolution" Cold Spring Harbor Laboratory Press, 2007 -
• Markov A.V. and etc. Macroevolution in wildlife and society. M.: URSS, 2008.

Notes

1. Tchaikovsky Yu. V. The science of life development. Experience of the theory of evolution - M.: Partnership of scientific publications KMK, 2006. - .

Biological evolution - irreversible, directed, historical development of living nature, accompanied by changes in the genetic composition of populations, the formation of adaptations, the formation of new and extinction of old species, changes in biogeocenoses and the biosphere as a whole.

Evolutionary teaching studies the general patterns and driving forces of the development of life on Earth. When studying the evolutionary process, it is advisable to distinguish two levels: the population-species level and the levels of supraspecific order (families, genera, orders, etc.). Populations and species are structures that actually exist in time and space; supraspecific orders are the unification of actually existing species into larger systematic taxa based on certain characteristics, primarily related to their common origin. Therefore, in evolutionary teaching there are two sections: microevolution and macroevolution.

Microevolution - this is the initial stage of evolutionary changes that occurs within a species and leads to the formation of new intraspecific groups, and ultimately to the formation of new species. Macroevolution- studies the evolution of supraspecific orders. The basic processes leading to micro- and macroevolution are similar. The fundamental difference lies in the time during which these processes occur: microevolution - tens and hundreds of thousands of years, macroevolution - millions of years.

Methods for studying evolution:

For microevolution analysis

1. Population genetic method (studies the genetic structure of populations, analyzes changes in the gene pool of populations over time, as well as the intensity of the mutation process in populations)

2. Hybridological method (allows us to analyze the role of combinative variability in the phenotypic diversity of individuals within a species)

3. Ecological methods (allow us to clarify the role of biotic and abiotic factors affecting the structure and dynamics of species). Diverse in their forms: observation, experiment, modeling.

To analyze macroevolution

1. Paleontological

a) study of fossil transitional forms (Devonian Ichthyostega, Jurassic proto-bird Archaeopteryx, animal-like reptile Lycaenops)

b) restoration of phylogenetic series - a sequence of fossil forms related to each other in the process of evolution (series of mollusks, horses)

2. Morphological methods - based on the principle: the internal similarity of organisms can show the evolutionary relationship of the compared forms. The structure of homologous organs, rudimentary organs, atavisms, and histological features of tissues are studied.

3. Embryological methods are aimed at identifying embryonic similarities and studying recapitulation. The law of germinal similarity was formulated by K. Baer: “The earlier stages of ontogenesis are studied, the more similarities are found between organisms.” The essence of recapitulation lies in the fact that at the beginning of embryonic development, many structural features of ancestral forms seem to be repeated (recapitulated): in the early stages of development, the characteristics of more distant ancestors are repeated, and in later stages - of close ancestors.

1. Methods of biochemistry and molecular genetics study the structure of proteins and nucleic acids of organisms belonging to different families, orders, classes. Based on the degree of differences in the structure of proteins and nucleotides, the degree of phylogenetic relationship of various taxa can be determined.

The doctrine of microevolution

The main processes leading to microevolution occur within a species, in intraspecific groups. Individuals of any species are distributed unevenly within the species range. The centers of the largest concentration of individuals are separate populations of this species. It is in populations that events occur that lead to the formation of new species. Therefore, populations are elementary evolutionary units.

Population- a minimal self-reproducing group of individuals that inhabit a certain space for a long time, forming an independent genetically open system. A species, unlike a population, is a genetically closed system: there are various barriers that prevent individuals from interbreeding different types. These barriers are called "isolation". There are different types of populations: island and ribbon.

Basic characteristics of the population.

1. 1. Environmental characteristics.

1. Population range(natural barriers, radius of individual activity, availability of food, mating partner, number of individuals). There are:

a) trophic area

b) reproductive range

2. Number of individuals in the population(fertility, duration of the life cycle, time to reach the reproductive period). Special meaning has a minimum number of individuals, upon reaching which the population may disappear for various reasons (anthropogenic impacts, natural disasters, diseases within the population).

3. Population dynamics. The size of any population is subject to constant fluctuations as a result of the influence of various biotic and abiotic factors. These fluctuations in numbers are called “population waves.” Population waves can be seasonal, or periodic (insects, annual plants) and non-periodic (changes in the prey-predator system, favorable conditions in the food chain - the presence of a large amount of food).

4. Age composition of the population determined by the presence of individuals of different age groups in the population. Disruption of population reproduction and, as a result, population aging is the first step towards its extinction.

5. Sex composition of the population determined by primary, secondary and tertiary sex ratio. The sex structure of a population is the numerical ratio of males and females in different age groups. We can talk about sex ratio only if there are individuals of different sexes in the population. The main genetic mechanism determining the sex ratio is heterogamety of either sex.

1. 2. Genetic characteristics of the population

1. Population gene pool- the totality of all genes of individuals in a population. This set includes genes that were passed on from previous generations and genes that arose at a given historical moment in the existence of the population. Newly emerged genes do not manifest themselves phenotypically (since most of them are recessive), but their presence in the future can significantly affect the fate of the population.

2. Genetic heterogeneity of the population characterized by the diversity of genotypes of individuals in a population. Any individual has its own individual genotype, which determines the individuality of phenotypic characteristics. The main mechanisms of this individuality are combinative variability and the mutation process.

Genetic processes in a population. The main genetic characteristics of the population are the frequency of occurrence:

Genes (quantitative ratio of alleles)

Genotypes (quantitative ratio of genotypes)

Phenotypes (quantitative ratio of phenotypes)

The ratios of these indicators are based on the mechanisms of combinative variability: the distribution of chromosomes and genes during meiosis and the random fusion of gametes during fertilization.

A mathematical justification for these ratios was proposed by J. Hardy and G. Weinberg; their law allows one to calculate the relative frequency of genotypes and phenotypes in a population. But it should be remembered that this law applies to an ideal population, and one of the main criteria of a given population is its large size. In other words, the relationships between genes and genotypes in populations can only be maintained when there are a large number of individuals. In small populations, the ratios of genotypes may be disrupted. Domestic scientists N.P. Dubinin and D.D. Romashev found that in small populations, due to random reasons, heterozygous individuals disappear, and the population becomes genetically homogeneous. Individuals with genotypes AA and aa begin to predominate in it. This phenomenon is called “genetic drift” or genetic-automatic processes.

Maintaining certain ratios of genotypes in a population leads to the presence in it intrapopulation polymorphism - the existence in a population of two or more different genetic, and, consequently, phenotypic, groups in a state of long-term equilibrium. Examples: people with different blood types, blondes and brunettes, blue eyes and brown eyes, etc.

The genetic heterogeneity of a population determines not only the phenotypic diversity of individuals, but also affects the historical perspective of the existence of the population and the species as a whole. But no matter how diverse the gene pool of a population is, it cannot by itself ensure the evolutionary process: it must be influenced by some factors. And these factors are called elementary evolutionary factors.

Elementary evolutionary factors.

1. Mutation process. When assessing the role of mutations in evolutionary processes, the following should be noted:

The mutation occurs in one individual and is passed on to one daughter. Subsequently, with the change of generations, the process of accumulation of mutations in the population occurs;

During sexual reproduction, only generative mutations can be transmitted to descendants;

The mutation must not adversely affect the viability or reproductive functions of the organism, i.e. in terms of biological significance it should be neutral. And the harmfulness or usefulness of a mutation will manifest itself in the course of natural selection. But it should also be remembered that harmfulness and usefulness are relative. Examples, flightless forms of insects on the islands (C. Darwin), upright walking - human diseases, sickle cell anemia - malaria;

Mutations can change any hereditary characteristics and properties of the organism;

The manifestation of mutations depends on the genetic environment into which the mutant gene enters. This is reflected in the phenotypic characteristics of gene expression - expressivity and penetrance.

When considering the role of mutations, it should also be taken into account that the resulting mutation leads to the disappearance of a previously existing characteristic (property). The gene pool of a population is the result of long-term selection of the best combinations of genes. Therefore, evolutionary mechanisms have emerged that limit genetic variability:

At the organismal level: mitosis and meiosis

At the cellular level: chromosome pairing - conversion of mutations to heterozygous

state

At the DNA level: repair mechanisms

The significance of the mutation process. Maintains a high degree of heterogeneity of natural populations, thereby creating the basis for the action of other evolutionary factors. The mutation process is the supplier of elementary evolutionary material.

2. Population waves. Changes in the number of individuals are characteristic of any population. This occurs as a result of the action of various abiotic and biotic factors, which can lead to an increase or, conversely, a decrease in population size. And fluctuations in numbers can be different: thousands, hundreds of thousands, and even millions of times. In a population that has experienced a decline, allele frequencies may differ significantly from the original population. The remaining gene pool will determine the new genetic structure of the entire population during the next increase in numbers. In this case, previously existing mutations in small concentrations may disappear, and the concentration of other mutations may randomly increase. In this case population waves act as a supplier of evolutionary material.

As the population size increases, individuals migrate, which leads to an expansion of the population range. There may be different habitat conditions at the boundaries of the range. And in different conditions Predominant reproduction of certain groups of organisms may be observed. An example is melanism in butterflies. In this case population waves contribute testing new genotypes to identify the usefulness or harmfulness of traits.

3. Insulation - the emergence of any barriers preventing free crossing. The obstacle to crossing leads to the consolidation and increase of differences between populations.

In nature, there is spatial isolation and biological isolation. Spatial isolation can exist in two forms: isolation by any barriers (water, land, mountains) and isolation by distance, which is determined by the possibility of interbreeding of closely living individuals.

Biological isolation can be divided into pre-copulatory (eliminating crossing) and post-copulatory.

Precopulatory isolation is represented by the following forms: ecological-ethological (organisms occupy different ecological niches: swamp and forest birds; different timing of gamete formation, different mating and nesting instincts) and morphophysiological isolation (size of organisms, differences in the structure of reproductive organs).

Post-copulatory or intrinsic genetic isolation is caused by mechanisms that disrupt the fusion of gametes, the normal development of the embryo, the emergence of sterile hybrids, and reduced viability of hybrids.

Insulation value: consolidates and strengthens the initial stages of genetic differentiation of the population.

The driving and guiding elementary evolutionary factor is certainly natural selection.

Natural selection is carried out in nature through the struggle for existence, both in direct form (intraspecific and interspecific) and in indirect form (struggle against unfavorable environmental conditions). C. Darwin substantiated the premises of natural selection:

Uncertain variability (genotypic - modern term)

“Any sign that is insignificant at first glance, when environmental conditions change, can play a decisive role in the struggle for life”

The desire of organisms to reproduce exponentially.

Charles Darwin wrote: “ The preservation of favorable individual differences and variations, and the destruction of those which are unfavorable, I call NATURAL SELECTION, OR SURVIVAL OF THE FITTEST.”

However, in the course of natural selection, what matters is not survival or death, but the differential reproduction of individuals. The very fact of survival without leaving offspring will have no consequences for evolution. Only those individuals that can leave numerous offspring are promising for evolution. Therefore, in the modern interpretation, natural selection is the selective preservation and reproduction of genotypes. But the selection of genotypes occurs exclusively through the selection of phenotypes, since the phenotype reflects the characteristics of the genotype. And at the same time, natural selection affects all vital signs and properties.

Currently, there are more than 30 forms of natural selection, but the main forms can be called: stabilizing, driving, disruptive, sexual selection.

1.Stabilizing selection- this is the preferential survival of organisms that have characteristics that do not have noticeable deviations from the norm characteristic of a given population. This selection takes place under stable conditions of the population. Classic example: G. Bumpas - 1911 - Manhattan - 327 sparrows numb from frost and blizzard: deviations in the average value for any trait (wing length, tarsus length, beak height, weight and body length) contributed to the elimination of individuals from the population. The action of stabilizing selection explains all cases of preservation of characteristics at any level of organization: 2 eyes, a five-fingered limb, body weight, a certain level of hormones (45, XO), etc. But stabilizing selection does not prevent the accumulation of mutations, which at this stage of the population’s existence do not manifest themselves phenotypically. This leads to the creation of a reserve of hereditary variability. When environmental conditions change, this variability serves as material for the transformation of the population under the influence of driving selection.

2. Driving selection leads to a shift in the reaction norm of a trait towards an increase or decrease. With directed changes in the environment, individuals with individual characteristics that correspond to these changes survive. A classic example: the neck and limbs of a giraffe. Traits that promote survival at low temperatures: increased fertility, increased size of the liver and heart (increased energy metabolism), increased body size (decreased heat transfer) are the result of driving selection. This form of selection leads to the emergence of new adaptations through a directed restructuring of the gene pool of the population.

In nature, driving and stabilizing selection constantly coexist together, and we can only talk about the predominance of one or another form in a given period of time for a given trait.

3. Disruptive selection aims to divide the original population into two or more different morphological groups.

The three forms of selection listed above characterize three possible states of the population: its immutability, unidirectional change and multidirectional change leading to fragmentation.

4. Sexual selection- occurs between individuals of the same sex for the opportunity to participate in the sexual process. In this case, bright colors, features of singing and shouting, weapons for tournament combat, and the development of the muscular system play a role important role in determining a partner.

Paths and methods of speciation

The interaction of elementary evolutionary factors leads to the final result of microevolution - speciation. Speciation is the division (in time and space) of a previously single species into two or more. And from the position of genetics, speciation is the division of a genetically open population system into genetically closed systems of new species.

The following pathways of speciation are distinguished:

1. True - one population gives rise to two new species. In this case, the number of species increases.

2. Philitic - a new species arises through a gradual change over time of the same species without any divergence (divergence) of the original group. This form of speciation can only be proven with the use of paleontological material. One possible example is the evolution of horses.

3. Hybridogenic - a new species arises as a result of the hybridization of two already existing species. Most examples are associated with plants: cultivated plum (a hybrid of cherry plum and sloe), mountain ash, hybrid forms of raspberries, tobacco, and rutabaga. In animals - khanorik (a hybrid of a ferret and a mink).

In true speciation, two main modes can be distinguished: allopatric and sympatric speciation.

Allopatric speciation. In this case, the separating populations are spatially (geographically) isolated from each other.

Main stages:

1. Change in the genetic composition of the population, accumulation

reserve of hereditary variability.

2. Population waves: with increasing numbers

individuals in the population migrate, as a result

The population area is expanding significantly.

There may be different conditions at the boundaries of the range,

in which certain types of

divided groups of organisms.

With a decrease in the number of individuals, the original range

population may change: decrease or disintegrate

be two (or more). In the latter case, the original

the population is divided into two, and between them there arises

geographical insulation. But the early stages of the section

population, it is relative: individuals are more likely to cross-breed

differ within their own population than with the neighboring one.

3. Geographically isolated populations are defined

For some time, they exist in isolation. In each of them

additional mutations occur that lead to

lead to the formation of different gene pools. And this

leads to the emergence of various forms of biological

ical isolation, including genetic isolation. From the moment

the emergence of two genetically closed systems, we

has the right to talk about the emergence of two new species from

single population.

At all stages, natural selection plays the main role.

Sympatric speciation- speciation occurring within the original range of a species on the basis of non-spatial isolation. Researchers identify several isolation options that can separate a primarily single population: chronological (according to the timing of reproduction), ecological and genetic.

Examples of speciation in lakes are given as chronological (seasonal) isolation. So, for example, in the lake. Sevan is home to an endemic species of trout, represented by several forms that differ morphologically, as well as in terms of spawning time.

Genetic isolation occurs as a result of a significant change in the karyotype of a group of individuals within the original population. Most often, mutations are represented by polyploidies. Polyploid forms are known in chrysanthemums, potatoes, and tobacco.

Evolution of phylogenetic groups

Among the forms we can distinguish primary ones - phyletic evolution and divergence, and secondary ones - parallelism and convergence.

Directions of evolution:

Arogenesis- development of a group with a significant expansion of the adaptive zone (a set of environmental conditions representing a possible living environment for a given group of organisms) and with access to others natural areas under the influence of the group’s acquisition of some large, previously absent adaptations (aromorphoses). The result of arogenesis is the emergence of new types and classes of animal and plant life.

Allogenesis- development of a group within one adaptive zone with the emergence of similar forms, differing in adaptations of the same scale (idioadaptation). The result is the emergence of orders, families, and genera within the class.

Biological discipline that studies patterns of historical development or evolution organic world. It generalizes the results obtained by special biological sciences, and therefore is the theoretical basis of biology.

The term "evolution" is used in biology as a synonym for the expression "historical development". Thus, its content does not coincide with the content of a similar term in philosophy, where evolution means part of the historical process - a smooth, gradual, quantitative change leading to revolution - an abrupt qualitative change. In biology, evolution is understood as the process of historical development of the organic world and an increase in the diversity of plants and animals through new formation, the gradual adaptation of living systems to continuously changing conditions of existence under the control of natural selection. As a result of evolution, in a number of successive generations, quantitative and qualitative changes occur in the form and function of organs and the way of life of organisms.

The term “evolution” (from Latin evolutio - deployment) was first used in biology in 1762 by the Swiss naturalist Charles Bonnet (1720-1793).

The founder of the theory of evolution was the English scientist Charles Darwin (1809-1882) [show] , who established in biology the idea of ​​​​the development of the organic world.

Charles Darwin

The hero of this story, a young Englishman named Charles, lived in the century before last. However, what happened to him makes me think about something even today.

A resident of a small English town, a student at the local gymnasium, Charles in his class turned out to be perhaps the most convenient target for ridicule from teachers and friends. Let's say right away: laziness was his main, but not his only, flaw. No matter how much the school teachers peered into his blue, always half-asleep eyes, there was not a single glimmer of curiosity or interest in any subject. He was too lazy to even learn his native English. With his whole appearance, he seemed to be asking: I speak, I write in English - what else is needed?

It should be noted that in this gymnasium, in addition to knowledge in the usual disciplines, students were also required to write poetry as one. In this regard, Charles was among the most hopeless: he could not (or did not want?) find a rhyme for the simplest words. "Charles!" - every now and then the teachers called out to him, seeing that the little bumpkin was once again trying to take a nap at his desk...

The most amazing thing is that he was from a very decent, well-known family in England. His father Sir Robert (two meters tall and weighing about two hundred kilograms) was considered one of the best doctors in the area. And Charles's paternal grandfather was an even more prominent figure - a world-famous botanist. Interestingly, he sometimes expressed his scientific views (unlike his grandson!) in poetic form...

Of course, not only geniuses studied in the gymnasium of this town. But Charles’s peers at least tried, crammed, passed off other people’s poems as their own, and after graduating from high school they entered universities and made successful careers. But the hero of our story didn’t even try to become better; he didn’t care, as they would say today.

However, no, he was interested in something too. For example, Charles loved to catch beetles, butterflies and make collections. But most of all - and this at a time when his classmates, striving to become true gentlemen, played golf, rode horses, learned to care for girls - Charles loved to sit with a primitive fishing rod on the shore of a local pond. Even if nothing was caught or even bitten, he sat for hours, looking at the water and did nothing! And when he grew up and received the right to carry a hunting weapon, they only saw him at home: the young man wandered all alone among the swamps and heathers, selflessly shooting at everything that flew and ran. And already after dark he returned home, hung with dead game...

The Honorable Sir Robert looked at his son with sadness and despair. There was not a single positive inclination visible in the offspring! But Charles himself, as he later admitted, unlike his father, did not grieve at all for this. Well, it’s not given, it’s not given – what can you do? The boy continued to calmly fish and go hunting...

Without any doubt that without him the unlucky Charles would not find his way in life, the obese Sir Robert, who suppressed his son with his obesity, sent him to an educational institution that trained doctors. Alas, the young man did not show the slightest interest in medicine, or in writing poetry. Sir Robert had to take him home.

Further, unfortunately or fortunately for Charles, a family friend will discover on the hulk’s head the so-called “bump of piety,” which in those days was considered the surest sign that its owner was destined to become an exemplary clergyman. (The lump was so large that, according to Charles himself, it could have been enough for a dozen priests!) Delighted, Sir Robert sent his son to the university, where future reverend fathers were given a good education. But Charles doesn’t bother studying here either. His first priority is still hunting, fishing and catching insects. It happens that a lazy person shoots at crows without even getting out of bed! Then he has another hobby, this time not entirely harmless: Charles goes to a pub and stays there until late. In a word, there is no hope left for the “lump of piety”...

Probably, everything could have ended badly for Charles if two eccentric university teachers had not paid attention to him. From interviews with him, they both came to the conclusion that this clumsy, but peace-loving and honest fellow brilliantly knows the habits of fish, birds, and insects. In addition, in some incomprehensible way, they discovered in him a tendency to scientific analysis. It was they who advised Charles to go on a trip around the world on a sailing ship as a laboratory assistant and collector of rare species of plants and animals. Charles, having nothing better to do, will agree. But there were two people against it: Sir Robert and the captain of the ship. The father decided that Charles, sailing the seas, would become completely lazy, and the captain thought that the dropout student would be an extra mouth on the ship.

And yet Charles was included in the expedition. The ship was called the Beagle. Sailing on the Beagle for five years, Charles, along with other members of the expedition, landed from time to time on the shores of the American continent, studied the flora and fauna of overseas countries, wandered in the endless pampas, climbed the highest mountains, lived for a long time on the Galapagos Islands, famous for their that birds and turtles that are not found anywhere else live here.

But Charles looks like a black sheep here too! Other members of the expedition, people much more experienced than he, set out on this journey to collect scientific material, and then, returning to England, summarize it and, having defended a dissertation, acquire a scientific degree. At the same time, many of them were in such a hurry that, while studying flora and fauna, they were always looking for something rare and sensational. What about slow Charles? He could sit by an ordinary burdock all day long, studying it from all sides, or look at a tiny bug with such genuine interest, as if it had arrived from another planet. So: Charles boarded the sailing ship Beagle as an ordinary laboratory assistant, with great doubts about the benefits of the trip, and returned to England... as a professional biologist, a brilliant scientist named Charles Darwin!

Having studied the unique scientific material collected in distant lands, after returning to England, he wrote a fundamental work on the origin and evolution of all life on earth, a work that revolutionized biological science. Without wanting it, the grandson eclipsed the glory of his famous grandfather.

True, his innate slowness will play a cruel joke on him more than once. Thus, a scientist who is accustomed to checking and rechecking the same facts more than once or twice, performing the same experiments, will delay the publication of the main work of his life for many years - the book “The Origin of Species”. Meanwhile, one young biologist who worked in the forests of Southeast Asia, independently of Darwin, would come to the same conclusions as the hero of our story. Only at the insistence of his friends would Darwin appear in print and prove his priority. And the first one to admit this will be that same young colleague - he revered the name of Darwin and did not at all doubt his honesty.

But even after what happened, the hero of our story will remain indifferent to vanity and glory. If it takes him eight years to create his first work, then it will take him thirty to create the next one. He worked really slowly, but for sure. One of Darwin’s biographers wrote about the peculiarities of his mind and talent: “In such a brain, thought matures so slowly that at first it seems as if it is almost not there, and then it becomes clear that it has always been there...”

Based on materials from: www.peoples.ru

This idea was put forward by many philosophers and naturalists earlier, but only Darwin, having collected enormous factual material, was able to provide irrefutable evidence of the evolutionary process and establish the factors under the influence of which the evolutionary development of species occurs.

The theory of evolution of the organic world developed by Darwin was called “Darwinism”. Its significance was so great that it sharply delimited the history of the development of evolutionary teaching, the important stages of which coincided with shifts in the socio-economic structure of society,

• pre-Darwinian period, which included
  • The era of practical before scientific knowledge(or speculative period)- from the Stone Age to the 16th century. This time was characterized mainly by the description of observed biological phenomena, on the basis of which the patterns of their development had not yet been established. Instead, speculative and often religious-idealistic interpretations were given.
  • The era of the emergence and formation of basic biological sciences (descriptive period)- from the 16th to the middle of the 19th century. This is the period of analytical development of biology, when the profession of naturalist appeared, scientists began to use experiment and tried to provide a biological basis for the practice of medicine, plant growing, and animal husbandry. At this time, a scientific system of knowledge about living nature was being formed, botany, zoology, taxonomy, morphology, physiology, embryology and other biological sciences were rapidly developing.
• Darwinian period or causal period ( era of synthesis of scientific biological knowledge) from the middle of the 19th to the middle of the 20th century. The first major synthesis of scientific knowledge was the theory of Charles Darwin, which gave a causal explanation of the historical development of the organic world.
• and the post-Darwinian period (or reconstruction period), in which, due to the rapid development of genetics and the use of its achievements to explain the mechanisms of evolution in the 20-30s of the 20th century. a new direction in the teaching of evolution was formed, called the synthetic theory of evolution ( era of modern Darwinism).

The pre-Darwinian period in the history of biology was characterized by the dominance of metaphysical ideas about the immutability and original purposiveness of nature. Metaphysicians viewed the phenomena and bodies of nature as once and for all data, unchanging, isolated and unrelated to each other. They believed that species of plants and animals are the product of a creative act and that from the very beginning organisms already had in ready-made form all the adaptations characteristic of them. Metaphysical thinking is anti-dialectical, and metaphysical ideas about nature merge with creationism and theology [show] .

Theology, or theology (Greek teos - god, logos - word) - a set of religious doctrines and teachings about the essence and action of God.

Naturalists of the pre-Darwinian period, while studying in depth the structure and vital functions of animals and plants, were amazed by the amazing perfection of organisms. This idea is well expressed in the words of the French naturalist J. Cuvier: “Each organized being constitutes an independent integral system, all parts of which mutually correspond to one another and serve to fulfill a specific purpose.” If the digestive organs are adapted for digesting meat, then the other organs of the animal - its teeth, jaws, limbs - are designed so that the animal can pursue prey, capture it, tear it into pieces and chew the meat. The instincts and morals of the animal must correspond to the same goal. The organism was presented as a single, intelligently arranged system. They were also amazed by the amazing correspondence between the properties of the organism and the conditions of their life. Every animal and plant has many adaptations that provide nutrition and preservation of life in certain environmental conditions, as if they were intelligently created precisely for these conditions.

Biologists of the pre-Darwinian period considered such a purposeful structure to be the original property of organisms and saw in it proof of the wisdom of the creator of the universe. On this occasion, in the 18th century, numerous works were published under headings of this type: “Theology of Shellfish” or “Theology of Fishes.” The authors of these works set out to prove, using examples of the expedient structure of animals, the wisdom of the creator of the universe. This was the “highest generalization” to which metaphysical thought in biology arrived.

“The highest generalizing thought to which the natural science of the period under review rose,” wrote F. Engels, “is the thought of the expediency of the orders established in nature, the flat Wolffian teleology, according to which cats were created in order to devour mice, mice in order to be devoured cats, and all of nature to prove the wisdom of the creator."

The idealistic doctrine of primordial expediency was called teleology (Greek teleos - striving for a goal). The materialistic explanation of expediency was first given much later by Darwin.

Ladder of Nature's Bodies. Another generalization that metaphysical natural science of the 18th century arrived at is the ladder of natural bodies. Studying animals, plants and bodies of inorganic nature, scientists arranged them according to the complexity of their structure in one stepped row. The starting point of the ladder was man. The remaining bodies of nature were arranged according to the degree of their similarity to humans in a descending row - animals, plants, bodies of inorganic nature. The author of one of the most popular “ladders of beings,” the Swiss scientist C. Bonnet (1720-1793), argued that between the lowest and highest levels of bodily and spiritual perfection there are countless intermediate steps. At the lower steps of the ladder, according to C. Bonnet, there are subtle matters, fire, air, water, then metals and minerals. From them he saw a transition through “stony algae” to the plant world, and through “sensitive plants” and polyps to the animal world. Animals were arranged in stages of increasing complexity from invertebrates to vertebrates, from fish to birds and quadrupeds, and finally through apes to humans.

It would seem that the ladder of the bodies of nature could prompt scientists to think about the development of nature from simple to complex, from lower to higher. However, the metaphysical worldview excluded the idea of ​​development. In the ladder of beings, metaphysicians saw only the order of frozen, unchanging bodies of nature established by the creator. It is interesting to note that S. Bonnet does not end his staircase with a man; on the steps of the ladder located above, he places various “angelic ranks” and ends it with a god.

However, even during the period of dominance of metaphysics and creationism in biology, some natural scientists focused their attention on the facts of variability and transformation of the forms of plants and animals. A movement known as transformism arose and developed. Transformism, the doctrine of the variability of plant and animal species, which undermined the foundations of metaphysics and creationism, is considered the predecessor of evolutionary doctrine.

The development of natural science in the 19th century, selection practice, expansion and deepening of research in various fields of biology, intensive accumulation of new scientific facts created favorable conditions for important evolutionary generalizations - a new research method that Charles Darwin used to substantiate the problems of evolution.

He substantiated the reality of a developing species as a category that arises, develops and disappears, substantiated the unity of discontinuity and continuity in the emergence of a species, dialectically solved the problem of randomness and necessity in evolution, showed how uncertain random changes under the influence of natural selection in a series of generations turn into adaptive signs of the species. Darwin revealed material causes and showed ways of forming relative expediency, thereby dealing the death blow to teleology for the first time. He developed fundamental scientific problems biology, established the historical method in the study of nature and proposed the first materialistic theory of the evolution of the organic world, rightly called Darwinism.

Darwinism is a materialistic doctrine about the general laws of the historical development of the organic world, about the driving forces, causes and paths of this development, as well as about the use of natural laws to control the life of plants and animals, their useful productivity, and morphogenesis in the interests of humans.

Darwinism had a fruitful influence on the development of biological science, during which Darwin's theory of evolution was confirmed.

Immediately after the advent of Darwinism, a sharp ideological struggle broke out in biology. Idealists of various persuasions, primarily creationists and representatives of other religious and philosophical movements, sharply opposed the materialistic foundations of the teachings of Charles Darwin. However, Darwinism showed the effectiveness of the provisions of dialectical-materialist philosophy about the constant development of nature as a result of the struggle of opposites, continuous movement and the universal connection of phenomena in nature.

The atheistic significance of Darwinism was so great, and the strength and convincingness of its provisions were so significant that even the head of the Catholic Church, Pope Pius XII, in his encyclical of 1950, allowed research on the origin of the human body from already existing living matter, but at the same time noted that the Catholic faith obliges hold the opinion that the soul was created directly by God.

The founders of Marxism-Leninism immediately paid attention to Darwin's work and highly appreciated his theory. K. Marx noted that Darwin was the first to deal the death blow to teleology and give a rational explanation of the relativity of adaptations in living nature. K. Marx pointed out that Darwin's book "The Origin of Species" is a good natural-historical basis for dialectical-materialist philosophy.

In his classic works “Dialectics of Nature”, “Anti-Dühring”, “L. Feuerbach” and others, F. Engels emphasized that it was Darwin who dealt a crushing blow to metaphysical views on nature and scientifically substantiated its evolutionary development. Already three weeks after the first publication of the book “The Origin of Species,” F. Engels wrote to K. Marx about Darwin’s successful development of evidence for the historical development of nature. Engels considered Darwin's theory one of the three largest generalizations of natural science in the 19th century.

V.I. Lenin in his work “What are “friends of the people” and how do they fight against the Social Democrats?” (1895), confirming the thought of F. Engels, compares the merits of K. Marx with the merits of Charles Darwin and emphasizes that Darwin was the first to put biology on a completely scientific basis.

More than a century of history testifies that Darwinism has successfully stood the test of time and has shown its undoubted scientific advantages over numerous attempts to justify the leading laws of the development of nature. Darwin's evolutionary teachings had a huge revolutionary impact on science. It established the idea of ​​development, the historical method in the study of living phenomena, which led to a radical restructuring of all branches of biological science.

Subsequently, based on the synthesis of Darwinism, genetics, ecology and other biological sciences, taking into account the dialectical connection between genetic-ecological patterns and the laws of the historical development of life, starting from the 20-30s of the last century, a synthetic theory of evolution took shape, which can be considered as modern Darwinism.

In our era, Darwinism is still the most important scientific generalization of modern biology. The general theory of evolution, establishing patterns and revealing the process of historical development of the organic world, determines the relationships between modern forms of animals and plants and their ancestors, and shows the paths of historical transformations. It explores evolutionary changes in the modern era (microevolution), provides theoretical justification for more advanced genetic and selection methods of artificial selection and allows us to develop the scientific basis for the creation of new breeds and varieties, the introduction of new groups of microorganisms, plants and animals into culture; create more productive agrocenoses; intensify forestry, fishing and hunting industries; develop biological methods of pest control; learn the patterns of evolution of biogeocenoses, predict the results of human intervention in ecosystems, prevent possible imbalances in the biosphere, protect and rationally use flora and fauna.

Evolutionary doctrine, the theory of evolution is the science of the causes, driving forces, mechanisms and general patterns of evolution of living organisms.

The first stage of evolutionary teaching is associated with the activities of ancient philosophers (Heraclitus, Democritus, Lucretius, etc.), who expressed ideas about the variability of the surrounding world, including the historical transformations of organisms, and the unity of living and inanimate nature.

The first relatively successful artificial system organic world was developed by a Swedish naturalist Carl Linnaeus(1707-1778). He took the form as the basis of his system and considered it an elementary unit of living nature. Closely related species were united by him into genera, genera into orders, orders into classes.

To indicate the type he used two Latin words: the first is the name of the genus, the second is the species name (wild radish). This principle of double nomenclature has been preserved in taxonomy to this day.

Disadvantages of the Linnaean system was that when classifying he took into account only 1-2 characteristics (in plants - the number of stamens, in animals - the structure of the respiratory and circulatory system), which did not reflect true kinship, so distant genera ended up in the same class, and close ones - in different ones. Linnaeus considered species in nature to be unchangeable, created by a creator.

First consecutive theory of evolution living organisms were developed by a French scientist Jean Baptiste Lamarck(1744-1829). In the book " Philosophy of Zoology", published in 1809, Lamarck suggested that during life each individual changes and adapts to the environment. He argued that the diversity of animals and plants is the result of the historical development of the organic world - evolution, which he understood as stepwise development, the complication of the organization of living organisms from lower to higher forms and called “gradation.” He proposed a unique system of organizing the world, arranging related groups in it in ascending order - from simple to more complex, in the form of a “ladder.” But Lamarck mistakenly believed that changes in the environment always cause useful changes in organisms.

English scientist Charles Darwin(1809-1882), having analyzed huge natural material and data from breeding practice, in the main work “ Origin of species"(1859) substantiated evolutionary theory, revealed the basic patterns of development of the organic world.

He proved that the huge diversity of species inhabiting the Earth, adapted to living conditions, was formed thanks to multidirectional hereditary changes and natural selection that constantly arise in nature. The ability of organisms to reproduce intensively and the simultaneous survival of a few individuals led Darwin to the idea that there is a struggle for existence between them, the consequence of which is the survival of the organisms most adapted to specific environmental conditions and the extinction of the unadapted. He considered the gradual complication and increase in the organization of living beings to be the result of hereditary variability and natural selection.

The significance of Darwin's theory lies in the fact that he introduced the natural historical method into the study of nature: he established the main driving forces of the evolution of the organic world (hereditary variability and natural selection). The evolution of different species comes with at different speeds. For example, many invertebrates and reptiles have hardly changed over millions of years. And in the human genus, according to paleontologists, several species have arisen and died out over the past 2 million years.

From the standpoint of modern teaching the most important factors of evolution are mutations And natural selection. The combination of these factors is necessary and sufficient for the implementation of the evolutionary process. Selection directly affects the phenotypes of organisms; As a result, not individual traits and alleles are selected, but entire genotypes that have a reaction norm. In genetic terms, evolution comes down to directed changes in the gene pools of populations ( microevolution). Depending on the nature of changes in external conditions, different forms of selection can act on a population - driving, stabilizing and disruptive.

Modern evolutionary teaching enriched with data from genetics, molecular biology, and ecology.