When did Darwin's theory appear? The teachings of Charles Darwin are the basis of the modern theory of evolution

Darwin's main idea was that the evolution of species follows corresponding patterns in nature. Just as cultivated organisms were adapted to human needs as a result of artificial selection, so in nature organisms adapted to its conditions as a result of natural selection. The prerequisite for this is the fact that all organisms vary in a large number of characteristics. Nature then favors the fittest due to their higher chances of survival and reproduction. Thus, better adapted forms are preserved in the “struggle for existence.” In the constantly changing conditions of the surrounding world, the nature of the groups of animals and plants that make up the species changes. Finally, the latter can no longer interbreed and are thus naturally isolated from each other. The struggle for existence cannot be understood primarily as a chain of violent influences. Cold, heat, drought and dampness, in short - all the physical, chemical and biological conditions of the environment can only under certain conditions be favorable for certain individuals and lead to their selection. The fact that Darwin was strongly influenced by the teachings of Malthus (1766-1834) initially led to an exaggeration of the role played by the element of struggle. This was already stated by Engels. In a letter to P.L. Lavrov (November 12-17, 1875), he wrote: “The interaction of natural bodies - both dead and living - includes both harmony and conflict, both struggle and cooperation. If we sum up all the rich diversity historical development under the one-sided and meager formula “struggle for existence”, a formula that even in the field of nature can only be accepted, but such a method condemns itself.” However, it seems that Malthus's influence on Darwin was somewhat exaggerated by Darwin himself. So, fitness is diverse: biochemical, physiological and morphological. Moreover, valuable adaptive traits may well be associated with insignificant and random traits. In the dialectical process, along with the necessary, the random also arises at the same time. What was still necessary in the evolutionary-historical sense yesterday may today take on the character of a secondary, random phenomenon, and vice versa.

Similarly, in natural selection, Darwin discovered a free law, far from any teleology and any conscious expediency and purposefulness, which determines the strengthening of fitness and the further development of organisms. The vast periods of time during which the process of biological evolution took place suggests that the amazing adaptability of organisms is not a miraculously created trait. Ignorance of the reasons for this adaptation for a long time made the area of ​​the living world a haven for teleological “proofs” of the existence of God, arising from the expediency of nature. On this issue, Darwin spoke as follows in a letter to Asa Gray: “Your question about what could convince me of this goal is very delicate. If I saw an angel descending from heaven, and if, thanks to the fact that others saw him, I was convinced that I had not gone crazy, then I would believe in predestination.” Darwin's explanation of the driving forces of evolution has often been considered unconvincing because of its supposed lack of direction and blindness. True, skeptics agreed that the long periods of time that evolution had at its disposal made it clear how something more complex could eventually emerge from something simple. But how, they asked, should we understand the emergence of an organ, for example, in a vertebrate animal? After all, before its improvement, this organ was absolutely incapable of performing its function, and, therefore, the previous stages of development did not have adaptability! Anyone who asks such a question does not take into account that “function and structure evolved simultaneously.” For example, the first light-sensitive organs in the evolution of animals were suitable only for perceiving the presence or absence of light. Possessing them was undoubtedly a valuable adaptation of the organism to the conditions of existence. In the course of further evolution, the improving organs of vision constantly began to give signals about new properties of the surrounding world: “about the direction from which the light comes, about the movement of the light source, its color and, finally - thanks to the display - about the distribution of illuminated objects in the surrounding world” . The difficulty mentioned above arises, therefore, only from the “unrealistic assumption that the first formations of the corresponding organ performed the same function as the fully developed organ.” What has been said regarding the formation of complex organs can be repeated, with some modifications, regarding the emergence of complex forms of behavior. In the course of evolution, they also underwent progressive functional changes, which contributed to the corresponding adaptation of organisms and thus, step by step, benefited their development. The duration of periods of speciation can be inferred, for example, from the fact that it took about 500,000 years for the formation of a new species in the evolution of the horse. For many mollusks, speciation took 2 to 3 million years. The duration of existence of a species in an unchanged form can be many times greater than the duration of its formation. The reason for this, of course, is that in a species already well adapted to environment, the likelihood of adding favorable changes becomes less. Thus, it is clear that the rhythm of speciation is often fast at first and then slows down. Under unchanging environmental conditions, well-adapted forms can safely remain in the “niches” they have conquered. Proof of the incipient process of speciation is complicated by the fact that, “as has been observed in birds, butterflies and other insects that now exist, the first deviations from normal development may be not of a morphological, but of a physiological order.” Representatives of the teleological worldview, as is known, assume that “not a single sparrow can fall from a tree without the will of God,” much less exhibit “unnecessary” properties. On the contrary, numerous facts of unnecessaryness and incongruity (di-teleology) in organisms prove the natural conditionality and relative limitations of adaptation processes. Thus, in a certain evolutionary period, there are redundant formations - for example, the rudimentary organs we have already mentioned represent only a “memory” of the lost features of adaptation. Sometimes such unnecessary organs become dangerous. This is proven by inflammation of the finger-shaped process in the human intestine, which until recently was not amenable to surgery and was identified only during autopsies as “volvulus.” There were and are also genuine inconsistencies. They led to the extinction of entire groups. Apparently, such incongruities never had adaptive value. Giant horns and saber-shaped teeth can serve as examples of this (however, their inappropriateness is disputed). Embryonic deformities represent a further branch of such diteleologies. They also only emphasize the universal adaptability of organisms. Of course, the latter is often hidden. In nature, epidemics or catastrophic climate changes sometimes occur, which destroy almost all individuals belonging to a given species. Only a few individuals, adapted to special, exceptional conditions, survive. In later times, it can be extremely difficult to establish the origin of the utility of such selective traits.

The creation of the theory of evolution by Charles Darwin (1809-1882) was prepared by the achievements of natural science of that period and high level development of capitalism. England first half XIX in, was a country with developed industry, agriculture and a major colonial power. It conducted brisk trade with many countries of the world, which increased the demand for raw materials and stimulated the development of methods of intensive crop and livestock production. Selection, the science of breeding new and improving existing plant varieties and animal breeds. The main method of selection at that time was selection and preservation for breeding of the best varieties of plants or animal breeds.
Breeders in England created valuable varieties of wheat and other grains, potatoes, fruit and ornamental plants, a number of breeds of large and small cattle, pigs, dogs, rabbits, pigeons, and poultry. However, their work did not have a theoretical basis. To study unexplored countries in search of sources of raw materials and new markets for goods, the British government organizes special expeditions in which scientists also take part. In one of them he committed trip around the world as a naturalist, young Charles Darwin. He collected a rich factual material, which served as a source for the development of the theory of evolution.
The most important scientific prerequisites for Darwin's theory were also Charles Lyell's theory of gradual changes in the Earth's surface under the influence of natural forces, the successes of paleontology, comparative embryology and systematics. The cell theory (1839), which convincingly showed the unity of the structure of plants and animals, was important in establishing the principle of the development of living nature. (N.E. Kovalev, L.D. Shevchuk, O.I. Shchurenko. Biology for preparatory departments of medical institutes.)

Expedition material by Charles Darwin ( V.B. Zakharov. Biology. Reference materials. M., 1997 )

Darwin's observations allowed us to wonder about the reasons for the similarities and differences between species. His main find, discovered in the geological deposits of South America, is the skeletons of extinct giant edentates, very similar to modern armadillos and sloths. Darwin was even more impressed by the study of the species composition of animals on the Galapagos Islands.
On these volcanic islands of recent origin, Darwin discovered closely related species of finches, similar to the mainland species, but adapted to different food sources - hard seeds, insects, nectar of plant flowers. Darwin concluded: the birds came to the island from the mainland and changed due to adaptation to new conditions habitat. Thus, Darwin raises the question of role of environmental conditions in speciation. Darwin observed a similar picture off the coast of Africa. Animals living on the Cape Verde Islands, despite some similarities with mainland species, still differ from them in significant features. From the point of view of the creation of species, Darwin could not explain the developmental features of the tuco-tuco rodent he described, living in burrows underground and giving birth to sighted young, which then go blind. The above and many other facts shook Darwin's belief in the creation of species. Returning to England, he set himself the task of resolving the question of the origin of species.

Charles Darwin, in his main work “The Origin of Species by Means of Natural Selection” (1859), summarizing the empirical material of contemporary biology and breeding practice, using the results of his own observations during his travels and circumnavigation on the Beagle ship, revealed the main factors of evolution organic world. In the book “Changes in Domestic Animals and Cultivated Plants” (vol. 1-2, 1868), he presented additional factual material to the main work. In the book “The Origin of Man and Sexual Selection” (1871), he put forward the hypothesis of the origin of man from an ape-like ancestor.

Darwin's theory is based on the ability of organisms to repeat similar types of metabolism and individual development in general - a property of heredity.

Heredity, together with variability, ensures the constancy and diversity of life forms and underlies the evolution of living nature.

Darwin used one of the main concepts of his theory of evolution - the concept of "struggle for existence" - to designate the relationships between organisms, as well as the relationships between organisms and abiotic conditions leading to the death of less adapted individuals and the survival of more adapted individuals.

The concept of "struggle for existence" reflects the facts that each species produces more individuals than survive to adulthood, and that each individual, during its life, enters into many relationships with biotic and abiotic factors environment.

Darwin identified two main forms of variability:

Certain variability - the ability of all individuals of the same species under certain environmental conditions to react in the same way to these conditions (climate, soil);

Uncertain variability, the nature of which does not correspond to changes in external conditions.

In modern terminology, undefined variability is called mutation.

Mutation is an indeterminate variability, unlike a definite one, that is hereditary in nature. According to Darwin, minor changes in the first generation are amplified in subsequent ones. Darwin emphasized that it is uncertain variability that plays a decisive role in evolution. It is usually associated with harmful and neutral mutations, but mutations that turn out to be promising are also possible.

The inevitable result of the struggle for existence and hereditary variability of organisms, according to Darwin, is the process of survival and reproduction of organisms most adapted to environmental conditions, and the death during the evolution of unadapted ones - natural selection.

The mechanism of natural selection in nature operates similarly to that of breeders, i.e. adds up insignificant and uncertain individual differences and forms from them the necessary adaptations in organisms, as well as interspecific differences. This mechanism discards unnecessary forms and forms new species.

The thesis of natural selection, along with the principles of the struggle for existence, heredity and variability, is the basis of Darwin's theory of evolution.

A. RUBTSOV, Ph.D. biol. Sci.

In 2009, the whole world celebrates the 200th anniversary of the founder of the theory of evolution, Charles Darwin, and the 150th anniversary of the publication of his work “On the Origin of Species.” Natural science museums around the world have taken on the difficult task of popularizing the teachings of the English scientist, towards whom public attitudes are still ambiguous to this day. It is the lack of information that is understandable and accessible to the general public that is one of the reasons for the difficult fate of the theory of evolution, which has become the basis of modern biology. In July 2008, an online interview took place on our portal, in which the head of the research department of evolution of the State Darwin Museum, candidate of biological sciences Alexander Sergeevich Rubtsov, answered questions from site visitors regarding the theory of evolution. We present the magazine version of this interview to our readers.

Science and life // Illustrations

According to modern criteria, the common and white-capped buntings should be considered one species: they do not differ in mitochondrial DNA, and hybrids can often be found in the area where they live together.

The Arabian talker is the most common inhabitant of the arid subtropics of the Middle East. In addition to the breeding pair, a family group of talkers can include up to 15 “helpers.”

The house in Doane where Charles Darwin lived for 40 years (1842 to 1882).

“Fur Labels” in the “Zoogeography” hall of the State Darwin Museum.

What's it like current state theory of evolution, what are its problem points?

In a nutshell, evolutionary theory constitutes the theoretical basis of all modern biology. As one of the founders of the modern synthetic theory of evolution, Theodosius Grigorievich Dobzhansky, rightly noted, “nothing in biology makes sense except in the light of evolution.” Take at least a school textbook - everything is there comparative anatomy is described from the point of view that amphibians evolved from fish, reptiles - from amphibians, etc. Actually, before Darwin’s theory, biology did not exist as an independent science: in order to study biology, one had to receive either a medical or theological education.

As in any science, the theory of evolution has many more questions than answers. The synthetic theory of evolution, combining the achievements of genetics and classical Darwinism, was created 80 years ago. It is now obvious to all evolutionary biologists that it is outdated, and many facts cannot be explained. Everyone is talking about the need for a new synthesis that would combine the achievements of paleontology, embryology, zoopsychology and other branches of biology that are not fully taken into account by modern evolutionary theory. But even if the third synthesis occurs (historians of biology call Darwin’s theory the first synthesis), then, obviously, it will not solve all the problems and will raise new questions - this is the specificity of science. In order not to be unfounded, I will outline several problems that are relevant to modern evolutionary theory. I want to say right away that this is just an illustration and not a critical review.

One of the problematic questions is: how do new species form? Although Darwin called his work “The Origin of Species,” he, as a scrupulously consistent scientist, honestly admitted that the question of how two new ones are formed from one ancestral species is far from being finally resolved. These words are still relevant today. Obviously, the main property of a species that allows it to exist as an integral autonomous unit in an ecosystem is its non-crossbreeding with other species, or, in scientific terms, reproductive isolation. It is ensured by a system of isolating mechanisms, which includes: differences between the habitats of closely related species, mating coloration and dissimilarity of mating rituals, non-viability and sterility of interspecific hybrids. The formation of isolating mechanisms is the main stage of the process of speciation. At the initial stages of speciation, the range of the ancestral species, due to some external reasons, is divided into several populations, separated from one another by geographical barriers for many millennia. In isolated populations, morphological and behavioral differences accumulate, which can subsequently act as isolating mechanisms. After some time, isolated populations may come into secondary geographic contact. If hybridization occurs in the contact zone, then the hybrids should be less viable than the parental forms, due to the genetic differences accumulated between them (the parental forms). Natural selection will promote the development of isolating mechanisms and a decrease in the level of hybridization. After some time, hybridization will stop and the speciation process will be completed. This is what the theory predicts. In practice, hybrids turn out to be quite viable and fertile, and hybrid populations prosper for a long time. And this is between such forms that, according to the level of genetic differences determined using modern methods DNA diagnostics are, of course, independent types. As molecular genetic studies have shown, hybridization can lead to secondary genetic similarity of hybridizing species even outside the contact zone, practically without affecting their appearance - phenotype. And what about the theory? And with the criteria of the species?

Darwin wrote his main book, On the Origin of Species by Means of Natural Selection, as summary more general work, which was never written by him. And he considered natural selection to be the main, but perhaps not the only factor in evolution. Perhaps it is worth returning to this remark of Darwin and thinking about what other possible factors of evolution besides selection. As such we can call cooperation. Indeed, all living organisms strive for a society of their own kind, at least temporarily - during reproduction and breeding. Cooperation often leads to stable social groupings with a hierarchical structure. In the course of evolution, the integration of a social group can go so far that its members can no longer exist separately from the group, and the entire society will have to be considered as a single superorganism. As paradoxical as it sounds, without cooperation, life on Earth would not have developed beyond bacteria. For any specialist with a higher biological education, it is obvious that our bodies are nothing more than highly integrated colonies of single-celled organisms. But the question is legitimate: is cooperation an independent evolutionary factor or one of many manifestations of selection? The answer is not obvious. For example, in passerine birds one can often see the following phenomenon: one-year-old birds, which do not have the opportunity to occupy their own nesting site, often help their parents feed their next offspring. This behavior could indeed have become entrenched through natural selection: by feeding younger brothers and sisters, birds increase the chance of survival of their own genes. However, in desert areas, where there are very few places suitable for nesting, the nesting pair has more and more helpers from year to year, and they risk spending their entire lives as auxiliary workers. Not wanting to put up with this state of affairs, the birds begin to sort things out at the nest, which usually leads to the death of the clutch or chicks. There is a selection against cooperation, but for some reason the social groupings of “helpers” are still preserved. Probably, cooperation is an independent evolutionary factor, acting on a par with natural selection. Darwin explained how natural selection arises and works. But where cooperation comes from is an open question.

In general, unsolved problems of evolutionary theory are an inexhaustible topic. These are questions of the direction of evolution, the relationship between gene and trait, etc.

How have scientists' views changed since Charles Darwin?

In short, ideas about selection have been supplemented by genetic data: genes are discrete units of heredity and can be combined with each other in various combinations from generation to generation; hereditary variability, which provides material for selection, is formed as a result of mutations; in addition to directional factors of evolution (natural selection), there are also stochastic ones (genetic drift); ideas about the nature of the action of selection have changed - it leads to a change in the ratio of gene frequencies in the population from generation to generation. Concepts about species and speciation have changed radically. In methodological terms, the naturalistic approach was supplemented by an experimental one, the theory became more formalized, and a rather complex mathematical apparatus appeared.

Is the theory of evolution the only logical explanation for the development of life?

Evolution is the development of life. Recognition that evolution occurs is the only logical explanation for the observed patterns of modern biological diversity, which is also confirmed by the fossil record and embryological data. The theory of evolution is an explanation of the mechanisms of evolution; there can be many theories of evolution. At the moment, the theory of natural selection (or rather, the synthetic theory of evolution as the “successor” of Darwin’s) is the only theory that meets the criteria of scientificity - verifiability and falsifiability: on the basis of this theory it is possible to build hypotheses that are tested empirically, and there is a possibility of their experimental refutation.

Has at least one new species been created through the process of artificial selection?

No, it was not created, because there was no such task. The main criterion for a species is its non-crossing with related species in nature. When breeding domestic breeds, no one set such a task: the purity of the breeds is maintained artificially. But such experiments were carried out with laboratory fruit flies: they carried out artificial selection for non-crossing between different lines. And they succeeded. Let’s imagine that someone suddenly decides on such an experiment: they release onto some uninhabited island, where there are no land predators (if such islands still exist), two breeds of dogs that differ greatly in size, say, bulldogs and dachshunds. If both breeds survive on the island, I think that after some time they will give rise to two different species. In general, the process of speciation is quite long. Molecular genetic studies have shown that it usually takes one to six million years for two isolated populations of small passerine birds to reach the species level of difference.

How valid are the arguments of opponents of the theory? Do the problems of accepting or not accepting a theory lie only in its superficial understanding?

It seems to me that all opponents of the theory of natural selection can be divided into three camps.

1. Rejection of the theory due to its alleged contradiction with the principles of universal morality and/or church dogmas.

These arguments have not changed in the 150 years since Darwin's theory was published. Lead in response scientific evidence evolution is meaningless: since the arguments of opponents of the theory are unscientific, then the answer should be the same. And I have it: I remember that in the 17th century, Galileo proved that the Earth revolves around the Sun, and not vice versa. What did they do to him? They forced me to renounce my beliefs because they contradicted the Holy Scriptures. Well, who was right in the end?

2. Scientific criticism of anti-Darwinists.

Quite a large number of scientists have consistently criticized the theory of natural selection and continue to do so. I cannot now fully cover this issue, so I recommend N. N. Vorontsov’s book “Development of Evolutionary Ideas in Biology,” where special attention is paid to this. Such criticism is quite constructive and useful. The only problem is that, as a rule, these scientists offer their own alternative theories, which in methodological terms turn out to be much weaker than the synthetic theory of evolution, or do not even meet the scientific criteria that I spoke about above.

3. Scientific criticism of Darwinists.

The theory of natural selection is so logically simple and understandable and supported by such a huge amount of facts that it simply cannot be wrong. Most biologists understand this. Another thing is that life is very complex phenomenon, and modern evolutionary theory gives only a greatly simplified picture. This creates the basis for further development of the theory through constructive criticism.

What is the situation with the evolution of Homo sapiens today? What does modern science think about the missing links of “relatives”?

Before talking about the transitional links between man and apes, I will say a few general phrases about transitional forms in general. The process of evolution is smooth and continuous, and it is possible to distinguish different stages, for example, time periods of the existence of individual species, only conditionally. By highlighting “transitional links”, we try to display the continuity of the evolutionary process using a discrete description language. And the “transitional link” is not the arithmetic mean between the two species being compared; it can and should have some of its own specific features that are absent in other species (after all, it – the “link” – must live somewhere and eat something) . To clarify what has been said, I will give an example. Let's say you didn't take physics at school and know nothing about the wave theory of light. Will it be easy for you to believe that green is a transitional link between red and violet? In the animal world, in fact, everything consists of transitional links. Amphibians are a transitional link between fish and reptiles. Dinosaurs are a transitional link between reptiles and birds. Apes are a transitional link between monkeys and humans. And everything is in order with the transitional links between chimpanzees and modern humans: the evolutionary series of humans is perhaps the most complete of those currently studied. Without being able to dwell on this issue in detail, I refer readers to the website http://macroevolution.narod.ru, where the modern ideas about the origin of man.

Why did man and ape survive, but intermediate forms did not? Can you imagine two highly developed civilizations of two different types of people existing in parallel and interacting little? Me not. It is even more difficult to imagine their peaceful coexistence if one of the civilizations were located more high level development than the other. In the Stone Age, people hunted large animals - mammoths, deer. What would they eat now: would they make regular raids on herds of cows and sheep? It is not difficult to imagine their future fate. Two species occupying the same ecological niche cannot coexist within the same territory - a well-known ecological rule. So one can only regret the absence of other species of people on Earth, but there is nothing to be surprised about. To be fair, it must be said that such a picture emerged relatively recently - 30 thousand years ago, when competition for food between tribes of hunters increased. Before this, for more than 4 million years different types the ancestors of modern man got along together. For example, in Europe, the tribes of Neanderthals and Cro-Magnons lived side by side for 30 thousand years. This is almost four times more than the age of modern civilization: the first states appeared approximately 7-8 thousand years ago.

What will the man of the future be like as a result of evolution?

Natural selection adapts random changes in the genotype to random changes in the environment. In addition to directional factors of evolution (natural selection), there are also stochastic ones (genetic drift). So it is possible to explain how evolution took place in the past, but alas, it is impossible to make predictions. I can only predict that if global cataclysms do not occur and humanity manages to avoid an environmental crisis associated with overpopulation, then the growth and life expectancy of people will increase slightly.

Are there estimated models of evolution as a result of a global catastrophe (asteroid impact or nuclear war)?

They probably exist, I don’t know. I can only give my assessment. Over the history of life on Earth, there have been many collisions with asteroids, but they have not led to mass extinctions on a planet-wide scale. Nevertheless, there were several mass extinctions, but they all occurred gradually (over several tens or hundreds of thousands of years) as a result of environmental crises. There is no clear answer to why environmental crises occur. Perhaps this is due to the “aging” of ecosystems: the evolution of species along the path of specialization and the appearance of voids in ecological niches, which have nothing to fill. The last environmental crisis, characterized by the fastest mass extinction of species in the entire history of the Earth, began 10 thousand years ago and is associated with the emergence of human civilization.

All species can be roughly divided into r- and K-strategists (the terms are taken from the names of the variables in the population growth equation); r-strategists are characterized by high fertility rates, weakly expressed care for offspring, high mortality of individuals (bacteria, mouse-like rodents), while for K-strategists the opposite is true (large mammals, humans). In the event of an environmental disaster, K-strategists are more likely to die, and r-strategists are more likely to survive.

Do museums display the latest advances in the theory of evolution in their exhibits? Who goes to the Darwin Museum?

From January to October 2008, the museum was visited by 301 thousand 157 people - that's about 1000 people a day. Since the museum exposition illustrates and complements school curriculum in biology, a significant part of the visitors are schoolchildren of all ages as part of excursion groups. But the museum cannot satisfy all requests for excursion services, because otherwise the guides would interfere with each other. We conduct 1,500 excursions per year, which is approximately 15% of total attendance. As survey results show, the main visitors to the museum - more than 80% - are parents with children. The museum builds its work with visitors precisely taking into account the fact that the main visitors to the museum are family groups. Teaching aids have been developed for all ages and for all thematic sections of the exhibition. With their help, visitors can independently and deeply familiarize themselves with the exhibition materials. Every year the museum hosts environmental holidays: water day, earth day, bird day, etc. Children and their parents are offered environmental games, quizzes and master classes, prizes await the winners, and there are no losers. Every year we come up with something new. The museum staff is trying to do everything so that, once in our museum, visitors want to come back here again and again.

This may sound somewhat immodest, but today among the museums of the world Darwin Museum most fully reflects the achievements of the theory of evolution. There are museums that are noticeably superior to ours in terms of exhibition space, technical equipment and attendance - for example, museums natural history in London, New York, Chicago - but they talk about how evolution happened. If there are exhibitions dedicated specifically to the driving forces of the evolutionary process, they are very modest. We try to show in our exposition the current level of knowledge on evolutionary topics, citing not only “classical” examples from textbooks, but also information from popular science and scientific articles, demonstrating the results of our own scientific research, and consulting with experts. In particular, the museum maintains close scientific ties with the Department of Biological Evolution of Moscow State University and the Institute of Ecology and Evolution. A. N. Severtsova. If you show the current level of science, problematic and unresolved issues, then visitors may get the impression that in general everything in the theory of evolution is shaky and incomprehensible. Therefore, we try to show already “established” indisputable facts, albeit not so “modern” - 20-30 years ago. I cannot say how often exhibitions change in museums around the world - it depends on the policy of a particular museum. Our exposition is relatively young, it is just over 10 years old, but during this period we have almost completely updated it.

In my opinion, our museum lags somewhat behind Western ones in the means of museum display. IN European museums visitors are constantly offered something to touch, move, listen to, and all interactive means are organically woven into the overall logical outline of the exhibition. Our museum is still more “academic”: the main means of presenting material are exhibits and accompanying texts. But here we are not standing still: new interactive exhibits periodically appear in the permanent exhibition - audio blocks, “live labels”, “fur stands”, etc. (come and see for yourself). The interactive complex “Walk the Path of Evolution” is being prepared for commissioning; there are plans to remodel the “Stages of Knowledge of Living Nature” hall according to the principle of an interactive exhibition.

Do people in Great Britain know who Charles Darwin is? Or is he, like Dickens, in oblivion there?

Everyone in Great Britain knows Darwin, if only because his portrait is depicted on the ten-pound note. And he is revered as a great scientist: his grave is located in Westminster Abbey next to Newton’s grave. Another thing is that, as throughout the world, the general public has an ambiguous attitude towards his scientific works.

There is a Darwin Museum in Great Britain. It is located in the London suburb of Down, the house where Darwin lived with his family. There is a small exhibition on the theory of evolution, but overall it is a house-museum of a scientist. The Natural History Museum in London recently opened a new Darwin Centre, an extension to the main museum building. In essence, this is a storage facility where the museum’s scientific collections are stored. There, in particular, there are the collections of Darwin himself, which he made during his voyage on the Beagle, and this is all that connects the center with the scientist. As museum staff explain, they named the museum's scientific collections repository after Darwin to highlight his contribution to the formation of biology as a modern scientific discipline. The Darwin Center is accessible to visitors, where they can get acquainted with the purpose and specifics of scientific collections, the conditions of their storage and the work of scientific staff.

I wonder why most of the lawsuits against the teaching of Darwin's theory in schools occur in the USA - an English-speaking country, an eternal ally of Great Britain?

Lawsuits against the teaching of Darwin's theory took place not only in the USA, but, for example, also in Serbia, Italy, and now in Russia. But only in the United States were legal proceedings against Darwin successful. This is most likely due to the political structure of the States. In any other country, a ban on teaching would have to be introduced everywhere, which is impossible, since without evolutionary theory biology will cease to exist as a science. And in the USA, the procedure for making court decisions is simplified: if you don’t like the laws of one state, move to another. Many people live there like that.

Charles Darwin's theory of evolution

Introduction

Biography of Charles Darwin

Anti-Darwinism

Conclusion

Introduction

The term “evolution” (from the Latin evolutio - deployment) was first used in one of the embryological works by the Swiss naturalist Charles Bonnet in 1762. Currently, evolution is understood as an irreversible process of change in any system occurring over time, due to which something arises. something new, heterogeneous, standing at a higher stage of development. The process of evolution concerns many phenomena occurring in nature. For example, an astronomer talks about the evolution of planetary systems and stars, a geologist - about the evolution of the Earth, a biologist - about the evolution of living beings. At the same time, the term “evolution” is often applied to phenomena that are not directly related to nature in the narrow sense of the word. For example, they talk about the evolution of social systems, views, some machines or materials, etc. The concept of evolution takes on special meaning in natural science, where biological evolution is studied primarily. Biological evolution is the irreversible and to a certain extent directed historical development of living nature, accompanied by changes in the genetic composition of populations, the formation of adaptations, the formation and extinction of species, transformations of biogeocenoses and the biosphere as a whole. In other words, biological evolution should be understood as the process of adaptive historical development of living forms at all levels of organization of living things. The theory of evolution was developed by Charles Darwin (1809-1882) and outlined in his book “The Origin of Species by Means of Natural Selection, or the Preservation of Favored Breeds in the Struggle for Life” (1859).

Biography of Charles Darwin

Charles Robert Darwin was born on February 12, 1809 in Shrewsbury (UK). Charles's father, Robert Warring, practiced medicine. He was the son of the then famous poet and scientist Erasmus Darwin. Darwin's mother, Susanna, gave birth to her husband two sons (Charles was the youngest). She died when Charles was only 7 years old. 1818 - the youngest Darwin enters primary school. 1819 - Darwin goes to Dr. Betler's gymnasium. It is known that the future great scientist was not among the first students. The main subjects in the gymnasium were Latin, ancient Greek and other languages, as well as literature. Showing very mediocre results in the study of humanities, Darwin becomes interested in natural sciences.

He collected collections of minerals and insects and compiled herbariums. 1825 - Darwin enters the University of Edinburgh, intending (perhaps at his father's insistence) to become a physician. 1827 - after completing only two courses of study, Darwin leaves the University and enters Cambridge, intending to become a priest. Here he also did not achieve much success. At the same time, together with naturalists whom he met while studying at the University of Edinburgh, Darwin collected marine animals and studied them. He visits communities of naturalists and takes them Active participation, reads a lot about nature. This is how Charles Darwin's first scientific work appears, which, however, was not published. By the end of his studies at Cambridge in 1831, Darwin already had the status of a naturalist collector. One of his friends recommended Charles to Captain FitzRoy, who agreed to take the young scientist with him on a trip around the world. 1831 - 1836 - Charles Darwin travels around the world on the Beagle.

This journey gave him a wealth of material for subsequent work. In addition to nature, Darwin made observations from ethnography and anthropology. Soon after his return, Darwin, together with a group of other natural scientists, published the book “Zoology of the Voyage of the Beagle.” Having collected many collections during his voyage, Darwin was simply not able to process them all on his own, so he had to attract co-authors. This book includes the following sections: fossil and modern mammals, birds, reptiles and amphibians, insects. Darwin himself wrote a section on geology. 1839 - Darwin moves to London and marries his cousin Emma Wedgwood. In total, Charles and Emma had ten children during their marriage. Three of them died in early age, some others were painful. Darwin explained this by the fact that he and his wife were closely related. This theory was reflected in some of the scientist’s later works. In the same year, the first edition of the “Diary of Research” was published - a work that became the first in a series of many written based on the impressions and results of the trip.

In this book, Darwin addresses not only zoology and botany, but also political and ethnographic issues. In particular, he describes the plight of the South American Indians. 1839-1843 - during this period of time, five volumes of one of Darwin's most significant works, Zoology, were published. 1842 - Charles Darwin's work "On the Structure and Distribution of Coral Reefs" appears. In the same year, due to poor health, the scientist moved with his family to the Dawn estate (Kent). In addition, Darwin's first manuscript on the theory of evolution dates back to 1842. 1844 - Darwin's study "Geological Observations on Volcanic Islands" is published. 1845 - the second, expanded, edition of the "Research Diary" is published. 1846 - Darwin publishes another book, which was called "Geological Research in South America". All recent works were written based on research materials carried out during a trip around the world. In addition to the highly specialized works mentioned above, Darwin’s book “A Voyage Around the World on the Beagle Ship” was published in two volumes in the same period. The book was captivating with its interesting content and simplicity of presentation. Thanks Darwin became a famous scientist for his works. The first half of the 1850s - Darwin successfully studies the subclass of barnacles, publishes several monographs devoted to this group of animals. These works were of great importance for biology. 1858 - the first article on the theory of evolution appears in print 1859 - Charles Darwin's main work was published, entitled "The Origin of Species by Means of Natural Selection, or the Preservation of Favored Breeds in the Struggle for Life." animals and cultivated plants." This book is usually considered as a supplement to "The Origin of Species...". 1871 - Darwin's third scientific work on the topic of evolution is published. It was the book "The Descent of Man and Sexual Selection."

It was here that the scientist cited and examined in detail a lot of evidence for his theory of the origin of man from animals. 1872 - Darwin publishes an addition to his previous work, The Expression of the Emotions in Man and Animals. During his life, Darwin received many awards from various scientific communities in Great Britain. April 19, 1882 - Charles Darwin dies at his Doane estate.

Voyage on the Beagle 1831-1836

In 1831, after graduating from university, Darwin set off as a naturalist on a trip around the world on the Royal Navy expedition ship Beagle, from where he returned to England only on October 2, 1836. The journey lasted almost five years. Darwin spends most of his time ashore, studying geology and collecting natural history collections, while the Beagle, under the leadership of Fitzroy, carried out hydrographic and cartographic surveys of the coast. During the trip, he carefully records his observations and theoretical calculations. From time to time, whenever the opportunity presented itself, Darwin sent copies of the notes to Cambridge, along with letters including copies of parts of his diary, for relatives. During the trip, he made a number of descriptions of the geology of various areas, collected a collection of animals, and also made a brief description external structure and the anatomy of many marine invertebrates. In other areas in which Darwin was ignorant, he proved himself to be a skilled collector, collecting specimens for specialist study. Despite frequent cases of poor health associated with seasickness, Darwin continued his research on board the ship; Most of his notes on zoology were on marine invertebrates, which he collected and described during times of calm at sea. During his first stop off the coast of Santiago, Darwin discovers an interesting phenomenon - volcanic rocks with shells and corals, baked by the high temperature of the lava into solid white rock. Fitzroy gives him the first volume of "Principles of Geology" (eng. Principles of Geology ) by Charles Lyell, where the author formulates the concepts of uniformitarianism in the interpretation of geological changes over a long period. And the very first studies carried out by Darwin in Santiago on the Cape Verde Islands showed the superiority of the method used by Lyell. Darwin subsequently adopted and used Lyell's approach for theorizing and thinking when writing books on geology.

In Punta Alta, in Patagonia, he does important discovery. Darwin discovers a fossilized giant extinct mammal. The importance of the find is emphasized by the fact that the remains of this animal were located in rocks next to the shells of modern species of mollusks, which indirectly indicates a recent extinction, without signs of climate change or disaster. He identifies the find as an obscure megatherium, with a bony shell that, to his first impression, looked like a giant version of the local armadillo. This find generated enormous interest when it reached the shores of England. During a trip with local gauchos into the interior of the country to describe geology and collect fossil remains, he acquires an understanding of the social, political and anthropological aspects of the interaction between indigenous peoples and colonists during the period of the revolution. He also notes that the two species of rhea ostrich have different but overlapping ranges. Moving further south, he discovers stepped plains lined with pebbles and mollusk shells, like marine terraces, reflecting a series of land uplifts. Reading Lyell's second volume, Darwin accepts his view of the "centers of creation" of species, but his findings and reflections lead him to question Lyell's ideas about the persistence and extinction of species. On board were three Fuegians who had been taken to England during the last expedition of the Beagle about February 1830. They had spent a year in England and were now brought back to Tierra del Fuego as missionaries. Darwin found these people friendly and civilized, while their fellow tribesmen looked like "wretched, degraded savages", just as domestic and wild animals differed from each other. For Darwin, these differences primarily demonstrated the meaning of cultural superiority, but not racial inferiority. Unlike his learned friends, he now thought that there was no insurmountable gap between man and animals. A year later, this mission was abandoned. The Fuegian, who was named Jimmy Button, began to live the same way as other Aborigines: he had a wife and had no desire to return to England. Darwin witnessed in Chile strong earthquake and saw signs indicating that the ground had just risen. This uplifted layer included bivalve shells that were above the high tide level. High in the Andes, he also discovered mollusk shells and several species of fossil trees that typically grow on sandy beaches. His theoretical reflections led him to the conclusion that, just as when land uplifts, shells end up high in the mountains, when parts of the seabed are lowered, ocean islands go under water, and at the same time, barrier reefs and then atolls are formed around the islands from coastal coral reefs. In the Galapagos Islands, Darwin noticed that some members of the mockingbird family were different from those in Chile and were different from each other on different islands. He also heard that the shells of land turtles vary slightly in shape, indicating their island of origin. The marsupial kangaroo rats and platypus he saw in Australia seemed so strange that it made Darwin think that at least two creators were working simultaneously to create this world. He found the Australian aborigines to be "courteous and nice" and noted their rapid decline in numbers under the pressure of European colonization. The Beagle is exploring the atolls of the Cocos Islands in order to determine the mechanisms of their formation. The success of this research was largely determined by Darwin's theoretical thinking.

Fitzroy began writing an official account of the Beagle's voyage, and after reading Darwin's diary, he suggests including it in the report. During his journey, Darwin visited the island of Tenerife, the Cape Verde Islands, the coast of Brazil, Argentina, Uruguay, Tierra del Fuego, Tasmania and the Cocos Islands, from where he brought back a large number of observations.

He presented the results in the works “The Journal of a Naturalist” (1839), “Zoology of the Voyage on the Beagle” (1840), “The Structure and Distribution of Coral Reefs” (The Structure and Distribution of Coral Reefs, 1842), etc. One of the interesting natural phenomena first described by Darwin in the scientific literature was ice crystals of a special form, penitentes, formed on the surface of glaciers in the Andes.

The history of the writing and publication of "The Origin of Species"

Since 1837, Darwin began keeping a diary, in which he entered data on breeds of domestic animals and plant varieties, as well as ideas about natural selection. In 1842 he wrote the first essay on the origin of species. Beginning in 1855, Darwin corresponded with the American botanist A. Gray, to whom two years later he outlined his ideas. Under the influence of the English geologist and naturalist Charles Lyell, in 1856 Darwin began preparing a third, expanded version of the book. In June 1858, when the work was half completed, I received a letter from the English naturalist A.R. Wallace with the manuscript of the latter's article. In this article Darwin found an abbreviated summary of his own theory natural selection. Two naturalists independently and simultaneously developed identical theories. Both were influenced by the work of T.R. Malthus on population; both were aware of Lyell's views, both studied the fauna, flora and geological formations of island groups and discovered significant differences between the species inhabiting them. Darwin sent Lyell Wallace's manuscript along with his own essay, as well as sketches of his second draft (1844) and a copy of his letter to A. Gray (1857). Lyell turned to the English botanist Joseph Hooker for advice, and on July 1, 1858, they together presented both works to the Linnean Society in London. In 1859, Darwin published On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life, which showed variability species of plants and animals, their natural origin from earlier species.

The main provisions of the evolutionary teachings of Charles Darwin

The diversity of animal and plant species is the result of the historical development of the organic world.

The main driving forces of evolution are the struggle for existence and natural selection. The material for natural selection is provided by hereditary variability. The stability of the species is ensured by heredity.

The evolution of the organic world predominantly followed the path of increasing complexity in the organization of living beings.

The adaptation of organisms to environmental conditions is the result of the action of natural selection.

Both favorable and unfavorable changes can be inherited.

The diversity of modern breeds of domestic animals and varieties of agricultural plants is the result of artificial selection.

Human evolution is related to the historical development of ancient apes. The evolutionary teaching of Charles Darwin can be considered as a revolution in the field of natural science.

Prerequisites and driving forces of evolution according to Charles Darwin

In Darwin's evolutionary theory, the prerequisite for evolution is hereditary variability, and the driving forces of evolution are the struggle for existence and natural selection. When creating an evolutionary theory, Charles Darwin repeatedly turned to the results of breeding practice. He tries to find out the origin of breeds of domestic animals and varieties of plants, to reveal the reasons for the diversity of breeds and varieties and to identify the methods by which they were obtained. Darwin assumed that cultivated plants and domestic animals are similar in a number of ways to certain wild species, and this cannot be explained from the perspective of the theory of creation. This led to the hypothesis that cultural forms originated from wild species. On the other hand, plants and domesticated animals introduced into culture did not remain unchanged: man not only chose the species of interest to him from the wild flora and fauna, but also significantly changed them in the right direction, creating a large number of plant varieties and breeds from a few wild species animals.

Darwin showed that the basis for the diversity of varieties and breeds is variability - the process of the emergence of differences in descendants in comparison with ancestors, which determine the diversity of individuals within a variety or breed. Darwin believes that the causes of variability are the influence of environmental factors on organisms (direct and indirect, through the “reproductive system”), as well as the nature of the organisms themselves (since each of them specifically reacts to the influence of the external environment).

Having determined his attitude to the question of the causes of variability, Darwin analyzes the forms of variability and distinguishes three among them: definite, indefinite and correlative. Specific, or group, variability is variability that occurs under the influence of some environmental factor that acts equally on all individuals of a variety or breed and changes in a certain direction. Examples of such variability include an increase in body weight in all animal species with good feeding, changes in hair coat under the influence of climate, etc.

A certain variability is widespread, covers the entire generation and is expressed in each individual in a similar way. It is not hereditary, i.e. in the descendants of the modified group, when placed in other environmental conditions, the characteristics acquired by the parents are not inherited. Uncertain, or individual, variability manifests itself specifically in each individual, i.e. singular, individual in nature. With indefinite variability, various differences appear in individuals of the same variety or breed, by which, under similar conditions, one individual differs from others. This form of variability is uncertain, i.e. a sign under the same conditions can change in different directions.

For example, one plant variety produces specimens with different colors flowers, different intensities of color of petals, etc. The reason for this phenomenon was unknown to Darwin. Uncertain, or individual, variability is hereditary in nature, i.e. is persistently transmitted to offspring. This is its importance for evolution. With correlative or relative variability, a change in any one organ causes changes in other organs.

For example, dogs with poorly developed coats usually have underdeveloped teeth, pigeons with feathered feet have webbed toes, and pigeons with a long beak usually have long legs, white cats with blue eyes are usually deaf, etc. From the factors of correlative variability, Darwin draws an important conclusion: a person, selecting any structural feature, is almost “likely to unintentionally change other parts of the organism on the basis of mysterious laws of correlation.” Having determined the form of variability, Darwin comes to the conclusion that only heritable changes are important for the evolutionary process, since only they can accumulate from generation to generation. According to Darwin, the main factors in the evolution of cultural forms are hereditary variability and selection made by humans (Darwin called such selection artificial). What are the driving forces behind the evolution of species in nature?

Darwin considered the explanation of the historical variability of species possible only through revealing the reasons for adaptability to certain conditions. Darwin came to the conclusion that the fitness of natural species, as well as cultural forms, is the result of selection, but it was not produced by man, but by environmental conditions. Among the factors limiting the number of species (this means causing a struggle for existence), Darwin includes the amount of food, the presence of predators, various diseases and unfavorable conditions. climatic conditions. These factors can influence species abundance directly and indirectly through complex relationships. Mutual contradictions between organisms play a very important role in limiting the number of species. For example, sprouted seeds most often die because they sprouted on soil that is already densely overgrown with other plants. These contradictions become especially acute in cases where the issue concerns the relationships between organisms that have similar needs and a similar organization.

The scheme of action of natural selection in a species system, according to Darwin, boils down to the following:

Variation is common to every group of animals and plants, and organisms differ from each other in many different ways.

The number of organisms of each species that are born is greater than the number that can find food and survive. However, since the number of each species is constant under natural conditions, it should be assumed that most of the offspring die. If all the descendants of a species survived and reproduced, they would soon replace all other species on the globe.

As more individuals are born than can survive, there is a struggle for existence, competition for food and habitat. This may be an active life-and-death struggle or a less obvious one; but no less effective competition, as, for example, when plants experience drought or cold.

Among the many changes observed in living beings, some facilitate survival in the struggle for existence, while others lead to the death of their owners. The concept of "survival of the fittest" is the core of the theory of natural selection.

Surviving individuals give rise to the next generation, and thus “successful” changes are passed on to subsequent generations. As a result, each next generation turns out to be more and more adapted to the environment; as the environment changes, further adaptations arise. If natural selection operates over many years, then the latest offspring may turn out to be so different from their ancestors that they can be separated into an independent species. It may also happen that some members of a given group of individuals will acquire certain changes and find themselves adapted to the environment in one way, while other members, possessing a different set of changes, will be adapted in a different way; In this way, from one ancestral species, subject to the isolation of similar groups, two or more species can arise.

Scientists' opinions on Charles Darwin's theory

Some scientists compared the impression of a book to a flash of lightning, which suddenly illuminates the way for a person lost on a dark night. Others - with a bomb that Darwin threw from his peaceful rural home into the enemy camp. In France, scientists treated the theory with contempt. German anti-Darwinists produced a lead medal on which Darwin was depicted in an offensive caricature with donkey ears. The English geologist Sedgwick said with indignation that this theory was nothing more than a chain of soap bubbles, and ended his letter to Darwin like this: “Now - one of the descendants of the monkey, in the past - your old friend . Since Darwin's teachings undermined the foundations of religion, reactionary scientists set the clergy against him. “Science and Christ have nothing in common” - this is the conclusion that Darwin himself drew from his teaching. This explains the fact that Darwin's teaching met with furious resistance from all the reactionary forces of bourgeois society and, above all, from the church. Already in the first review of the book “On the Origin of Species,” Darwin’s teaching was criticized from the standpoint of theology, as fundamentally hostile to religion and irreconcilable with it. Darwin's materialistic theory of the origin of man aroused particular anger among theologians and scientists of the old school. About one critic, Darwin wrote to friends that the critic himself, perhaps, would not have burned him at the stake, but he would have brought him some brushwood and would have shown the black beasts how to catch him. Catholic priests organized a special academy to combat evolutionary teaching, calling it “bestial philosophy.” . The abuse and contempt of ignorant people upset Darwin, but he did not answer them. He valued only the opinions of people he respected. Advanced scientists greeted Darwin's theory with great enthusiasm. The German biologist E. Haeckel wrote that after reading this brilliant book, he felt like “a curtain fell from his eyes . Young Professor Huxley was ready to "go to the stake behind new idea. The path along which Darwin proposed to follow himself seemed to him not like an airy path of spider web threads, but a wide bridge along which one could pass over many abysses. F. Engels noted that Darwin dealt a powerful blow to idealistic ideas about nature by proving that the modern organic world is the product of historical development that lasted millions of years. He compared Darwin's merits in discovering the laws of the development of nature with the merits of Marx, who discovered the laws of the development of society. The Russian translation of "The Origin of Species" appeared in 1864. The spread of Darwinism in Russia coincided with the rise of the revolutionary movement, with the awakening of public consciousness after Crimean War, with the spread of the ideas of the great Russian democrats N.G. Chernyshevsky, A.I. Herzen, D.I. Pisareva. And although here there were attempts to turn the theory into an “incoherent heap of garbage , but with the help of numerous popularizers, Darwin's teachings became available to wide reading circles and were met with sympathy. DI. Pisarev called Darwin a brilliant thinker and wrote that Darwin talks about the laws of organic nature so simply and proves so irrefutably that anyone who reads his book is surprised how he himself did not come up with such clear conclusions a long time ago. But the main fighter in this battle of ideas was Darwin's book itself. Years passed, and Darwin's teachings spread like a stormy stream, sweeping away all obstacles along the way. Darwin was lucky during his lifetime to see the triumph of his ideas: not a year passed without him receiving some kind of award.

Anti-Darwinism

ANTI-DARVINI ?ZM (from the Greek "anti-" - against and Darwinism), a group of teachings that in one form or another deny the leading role of natural selection in evolution. They belong to this category as competitors evolutionary theories: Lamarckism, saltationism, catastrophism and more or less partial criticism of the main provisions of Darwinism. Anti-Darwinism and denial of evolution should not be identified as historical process(i.e. anti-evolutionism). Historically, anti-Darwinism arose as a critical reaction to the publication of “The Origin of Species” by Charles Darwin. These objections were most consistently and logically summarized in 1871 by Art. Mivart in the article “On the Formation of Species”:

) since deviations from the norm are usually small, they should not significantly affect the fitness of individuals;

) since inherited deviations arise randomly, they must be mutually compensated in a series of generations;

) the accumulation and consolidation of small deviations is difficult to explain the emergence of complex, integral structures, such as the eye or inner ear. In addition, according to Darwin, transitional forms should be widely represented in nature, whereas usually more or less clear breaks (hiatuses) are found between taxa, especially noticeable in paleontological material. Darwin himself drew attention to these objections in subsequent editions of his work, but was unable to explain them with reason. Because of this, competing evolutionary doctrines such as neo-Lamarckism and neo-catastrophism emerged in the second half of the 19th century.

By the beginning of the 20th century, numerous, often popular, works of mechanolamarckists demonstrated the possibility of “adequate variability and inheritance of acquired characteristics.” The first works of geneticists (H. de Vries and W. Batson) in practice proved the spasmodic, sudden nature of the occurrence of heritable changes, and not the gradual accumulation of changes under the influence of selection (the so-called genetic anti-Darwinism). Finally, many works have appeared that experimentally prove the “ineffectiveness” of natural selection. So, in 1903, V. Johannsen conducted a selection in clean lines beans, dividing the seeds into three groups by size: large, medium and small. He found that the offspring of each group reproduced a full range of seed sizes identical to the parent. From a modern point of view, this result is obvious - it is not the trait itself that is inherited, but the reaction norm. However, at the beginning of the 20th century, such works were perceived as a refutation of the principle of natural selection.

These circumstances determined the so-called. the crisis of Darwinism, or the “agnostic period in the development of evolutionary teaching,” which lasted until the 30s of the 20th century. The natural way out of the crisis was the synthesis of genetics and the population approach, as well as the emergence of a synthetic theory of evolution (see evolutionary doctrine).

The main results of evolution (according to Charles Darwin)

The main result of evolution is the improvement of the adaptability of organisms to living conditions, which entails the improvement of their organization. As a result of the action of natural selection, individuals with traits useful for their prosperity are preserved. Darwin provides a wealth of evidence for the increased fitness of organisms due to natural selection. This, for example, is the widespread use of cover colors among animals (to match the color of the area in which the animals live, or to match the color of individual objects. Many animals that have special protective devices against being eaten by other animals also have warning colors (for example, poisonous or inedible animals).

Some animals have a common threatening coloration in the form of bright, frightening spots. Many animals that do not have special means of protection imitate protected animals in body shape and coloring (mimicry). Many of the animals have needles, spines, chitinous cover, shell, shell, scales, etc. All these adaptations could only appear as a result of natural selection, ensuring the existence of the species in certain conditions. Among plants, a wide variety of adaptations to cross-pollination and the dispersal of fruits and seeds are widespread. In animals, various kinds of instincts play an important role in the quality of adaptations (instinct of caring for offspring, instincts associated with obtaining food, etc.).

At the same time, Darwin notes that the adaptability of organisms to their environment (their expediency), along with perfection, is relative. When conditions change dramatically, useful signs may turn out to be useless or even harmful. For example, in aquatic plants that absorb water and substances dissolved in it over the entire surface of the body, the root system is poorly developed, but the shoot surface and air-bearing tissue - aerenchyma, formed by a system of intercellular spaces permeating the entire body of the plant - are well developed. This increases the surface of contact with the environment, providing better gas exchange, and allows plants to better use light and absorb carbon dioxide. But when the reservoir dries out, such plants will die very quickly. All their adaptive characteristics that ensure their prosperity in the aquatic environment turn out to be useless outside it. Another important result of evolution is the increase in the diversity of species of natural groups, i.e. systematic differentiation of species. The general increase in the diversity of organic forms greatly complicates the relationships that arise between organisms in nature. Therefore, in the course of historical development, the most highly organized forms, as a rule, receive the greatest advantage.

Thus, the progressive development of the organic world on Earth from lower to higher is carried out. At the same time, while stating the fact of progressive evolution, Darwin does not deny morphophysiological regression (i.e., the evolution of forms whose adaptation to environmental conditions occurs through simplification of organization), as well as a direction of evolution that does not lead to either complication or simplification of organization living forms. The combination of different directions of evolution leads to the simultaneous existence of forms that differ in the level of organization.

Conclusion

The driving forces of evolution, according to Darwin, are hereditary variability and natural selection. Variability serves as the basis for the formation of new characteristics in the structure and functions of organisms, and heredity consolidates these characteristics. As a result of the struggle for existence, the most fit individuals primarily survive and participate in reproduction, i.e. natural selection, the consequence of which is the emergence of new species. It is important that the adaptability of organisms to the environment is relative.

Independently of Darwin, A. Wallace came to similar conclusions. A significant contribution to the propaganda and development of Darwinism was made by T. Huxley (in 1860 he proposed the term “Darwinism”), F. Müller and E. Haeckel, A.O. and V.O. Kovalevskiy, N.A. and A.N. Severtsov, I.I. Mechnikov, K.A. Timiryazev, I.I. Schmalhausen and others. In the 20-30s. XX century The so-called synthetic theory of evolution was formed, combining classical Darwinism and the achievements of genetics. As an integral materialist doctrine, Darwinism revolutionized biology, undermined the positions of creationism and vitalism, and influenced the 2nd gender. XIX century huge influence on the natural and social sciences, culture as a whole. However, even during Darwin’s lifetime, along with the widespread recognition of his theory, various currents of anti-Darwinism arose in biology, denying or sharply limiting the role of natural selection in evolution and putting forward other factors as the main forces leading to speciation. The debate on the main problems of the evolution of teaching continues in modern science.

theory of evolution Darwin anti-Darwinism

List of sources used

1.Natural selection (Electronic resource): #"justify">2. Natural selection. Darwin's theory (Electronic resource): #"justify">. The main provisions of Darwin's theory (Electronic resource): #"justify">. Theory of Charles Darwin (Electronic resource): #"justify">. Charles Darwin (Electronic resource): http://www.gumer. Info

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Darwin's evolutionary theory is a holistic doctrine of the historical development of the organic world. It covers a wide range of problems, the most important of which are evidence of evolution, identifying the driving forces of evolution, determining the paths and patterns of the evolutionary process, etc.

The essence of evolutionary teaching lies in the following basic principles:

1. All types of living beings inhabiting the Earth were never created by anyone.

2. Having arisen naturally, organic forms were slowly and gradually transformed and improved in accordance with environmental conditions.

3. The transformation of species in nature is based on such properties of organisms as variability and heredity, as well as natural selection constantly occurring in nature. Natural selection occurs through the complex interaction of organisms with each other and with factors of inanimate nature; Darwin called this relationship the struggle for existence.

4. The result of evolution is the adaptability of organisms to their living conditions and the diversity of species in nature.

4. Prerequisites and driving forces of evolution according to Darwin

In Darwin's evolutionary theory, the prerequisite for evolution is hereditary variability, and the driving forces of evolution are the struggle for existence and natural selection. When creating an evolutionary theory, Charles Darwin repeatedly turned to the results of breeding practice. He tries to find out the origin of breeds of domestic animals and varieties of plants, to reveal the reasons for the diversity of breeds and varieties and to identify the methods by which they were obtained. Darwin proceeded from the fact that cultivated plants and domestic animals are similar in a number of characteristics to certain wild species, and this cannot be explained from the perspective of the theory of creation. This led to the hypothesis that cultivated forms originated from wild species. On the other hand, plants and domesticated animals introduced into culture did not remain unchanged: man not only chose the species of interest to him from the wild flora and fauna, but also significantly changed them in the right direction, creating a large number of plant varieties and breeds from a few wild species animals. Darwin showed that the basis for the diversity of varieties and breeds is variability - the process of the emergence of differences in descendants in comparison with ancestors, which determine the diversity of individuals within a variety or breed. Darwin believes that the causes of variability are the influence of environmental factors on organisms (direct and indirect, through the “reproductive system”), as well as the nature of the organisms themselves (since each of them specifically reacts to the influence of the external environment). Having determined his attitude to the question of the causes of variability, Darwin analyzes the forms of variability and distinguishes three among them: definite, indefinite and correlative.

Specific, or group, variability is variability that occurs under the influence of some environmental factor that acts equally on all individuals of a variety or breed and changes in a certain direction. Examples of such variability include an increase in body weight in all animal species with good feeding, changes in hair coat under the influence of climate, etc. A certain variability is widespread, covers the entire generation and is expressed in each individual in a similar way. It is not hereditary, i.e. in the descendants of the modified group, when placed in other environmental conditions, the characteristics acquired by the parents are not inherited.

Uncertain, or individual, variability manifests itself specifically in each individual, that is, it is single, individual in nature. With indefinite variability, various differences appear in individuals of the same variety or breed, by which, under similar conditions, one individual differs from others. This form of variability is uncertain, i.e. a trait under the same conditions can change in different directions. For example, one variety of plants produces specimens with different colors of flowers, different intensities of color of petals, etc. The reason for this phenomenon was unknown to Darwin. Uncertain, or individual, variability is hereditary in nature, i.e. is persistently transmitted to offspring. This is its importance for evolution.

With correlative or relative variability, a change in any one organ causes changes in other organs. For example, dogs with poorly developed coats usually have underdeveloped teeth, pigeons with feathered feet have webbed toes, pigeons with a long beak usually have long legs, white cats with blue eyes are usually deaf, etc. From the factors of correlative variability, Darwin draws an important conclusion: a person, selecting any structural feature, is almost “likely to unintentionally change other parts of the organism on the basis of mysterious laws of correlation.”

Having determined the form of variability, Darwin comes to the conclusion that only heritable changes are important for the evolutionary process, since only they can accumulate from generation to generation. According to Darwin, the main factors in the evolution of cultural forms are hereditary variability and selection made by humans (Darwin called such selection artificial).

What are the driving forces behind the evolution of species in nature? Darwin considered the explanation of the historical variability of species possible only through revealing the reasons for adaptability to certain conditions. Darwin came to the conclusion that the fitness of natural species, as well as cultural forms, is the result of selection, but it was not produced by man, but by environmental conditions.

Among the factors limiting the number of species (this means causing a struggle for existence), Darwin includes the amount of food, the presence of predators, various diseases and unfavorable climatic conditions. These factors can influence species abundance directly and indirectly through complex relationships. Mutual contradictions between organisms play a very important role in limiting the number of species. For example, sprouted seeds most often die because they sprouted on soil that is already densely overgrown with other plants. These contradictions become especially acute in cases where the issue concerns the relationships between organisms that have similar needs and a similar organization. Therefore, the struggle for existence between species of the same genus is more severe than between species of different genera. Even more intense are the contradictions between individuals of the same species (intraspecific struggle).

The natural result of contradictions between organisms and the external environment is the extermination of some individuals of the species. If some of the individuals of each species die in the struggle for existence, then the rest are able to overcome unfavorable conditions.

Selection occurs continuously over an endless series of successive generations and preserves mainly those forms that are more consistent with given conditions. Natural selection and elimination of part of a particular species are inextricably linked and are a necessary condition for the evolution of species in nature.

The scheme of action of natural selection in a species system, according to Darwin, boils down to the following:

1. Variation is common to every group of animals and plants, and organisms differ from each other in many different ways.

2. The number of organisms of each species that are born is greater than the number that can find food and survive. However, since the number of each species is constant under natural conditions, it should be assumed that most of the offspring die. If all the descendants of a species survived and reproduced, they would soon replace all other species on the globe.

3. Since more individuals are born than can survive, there is a struggle for existence, competition for food and habitat. This may be an active life-and-death struggle or a less obvious one; but no less effective competition, as, for example, when plants experience drought or cold.

4. Among the many changes observed in living beings, some facilitate survival in the struggle for existence, while others lead to the death of their owners. The concept of "survival of the fittest" is the core of the theory of natural selection.

5. Surviving individuals give rise to the next generation, and thus “successful” changes are passed on to subsequent generations. As a result, each next generation turns out to be more and more adapted to the environment; as the environment changes, further adaptations arise. If natural selection operates over many years, then the latest offspring may turn out to be so different from their ancestors that they can be separated into an independent species.

It may also happen that some members of a given group of individuals will acquire certain changes and find themselves adapted to the environment in one way, while other members, possessing a different set of changes, will be adapted in a different way; In this way, from one ancestral species, subject to the isolation of similar groups, two or more species can arise.