The perception of Darwinian ideas by scientists has varied greatly both in different countries as well as within the same country. Evidence for a long evolutionary history of origin from common ancestors and from the simplest forms of life were universally accepted, but many scientists denied that it was the chain of natural selection that was the main cause of the changes. In England, Thomas Huxley and later George Romans ardently advocated natural selection. Alfred Russel Wallace, who discovered the principle of natural selection independently of Darwin, believed that this could not explain the ability of man to think. Lyell found that Darwin exaggerated the importance of selection, and such prominent scientists as Richard Owen, Adam Sedgwick and Lord Kelvin rejected this idea. Herbert Spencer, a prominent popularizer and defender of the theory of evolution, was a Lamarckian.
In America, the Harvard naturalist Asa Gray championed the idea of selection, although he believed that providential design might be the cause of change. And the highly influential editor of the American Naturalist, E. D. Cope, was a leading exponent of neo-Lamarckism. Harvard scientist Louis Agassiz was an ardent anti-Darwinist and an adherent of a form of philosophical idealism that believed that mind was behind creation. The author of a comparative study of scientists' responses to Darwinian theory concludes that "by the end of the century there were apparently more neo-Lamarckians than Darwinists among American scientists"79. In France, at first, biologists received Darwin's views rather coolly, but then he received support from the anti-clerical movement. As in other countries where ecclesiastical authorities criticized Darwin, some scientists supported him in part because they wanted to defend the independence of their fledgling professional group from ecclesiastical interference. In Germany, Ernst Haeckel combined Lamarckism with materialist philosophy.
We will define Darwinism as the belief that the natural selection of variation is the main (though not the only) source of evolutionary change. Why did many scientists at the end of the century defend views that were alternative to Darwinism?
First, at the scientific level, there were a number of unsolvable problems in Darwinism. Some physiological structures do not seem to be of any use, and the early stages of certain evolutionary changes do not appear to be related to adaptive function. There were still no developed theories explaining the occurrence and inheritance of variations, and many scientists tried to find alternative hypotheses. However, the Lamarckists failed to develop a reliable theory of inheritance that could explain how the physiological changes that occur during the life of an organism can be inherited by its descendants. Some representatives of developmental biology believed that the formation of the embryo (ontogenesis) repeats the history of species (phylogenesis). It was believed that a certain residual memory of those stages of development through which its ancestors passed through is embodied in a growing organism. But this was only a vague analogy, not a reliable theory.
Secondly, many representatives of developmental biology recognized that the growth of an organism is the unfolding of an internally laid down plan. Such ideas were often combined with the idea that the evolution of different species occurs in parallel due to the forces arising in the organisms themselves (orthogenesis). In their search for order in nature, biologists have discovered a tendency toward linear development, which they argued was the organism's internal predisposition to change in a certain direction, even if it leads too far and leads to the emergence of maladaptive traits (or to extinction), which, in their opinion, is impossible. explain the principle of selection. Biologists who shared these views were usually influenced by the idealistic philosophy that was strong in England and even more so in Germany. Idealism believes that all the structures of the material world are based on uniform organizing schemes or archetypes. Some idealists have argued that these fundamental forms are the ideas that exist in the mind of God, but not all idealists were theists.
Third, the philosophical assumptions of Lamarckism seemed more acceptable than those of Darwin. Instead of the relentless process of competitive struggle and external selection produced by the environment, the Lamarckians believed that the internal creative forces of organisms play a role in their evolutionary history (either through mental activity or through positive changes in physiology in response to demands environment). Thus, Lamarckism confirmed the belief that evolution is directed and progressive, in contrast to the unpredictability of variation and the random nature of selection in Darwin's theory. Even those who held theistic beliefs could retain a sense of purpose. The internal tendencies of organisms could reflect various forms of divine design. In any case, Lamarckism was a less radical break with earlier philosophical and religious assumptions than Darwinism.
Fourth, the social aspects of Lamarckism were much more optimistic than those of Darwin. If the choice of human behavior affects the inherited evolutionary future, then the possibility of rapid human improvement opens up bright prospects for social change (which is why the Soviet authorities gave their blessing to Lysenko when he tried to revive Lamarckism in the 1940s). Of course, Lamarckism could not serve as a guide to the question of what biological changes should be aimed at and what cultural changes might accompany them. Spencer was an ardent supporter of private enterprise, while Haeckel adhered to socialist views. The distinction between biological and cultural evolution has not been subjected to an appropriate critical analysis.
Attempts to confirm Lamarckism with laboratory experiments have led to questionable or ambiguous results, while Darwinism has often been able to offer an explanation for the findings. The distinction between genetic makeup (genotype) and physical appearance (phenotype) was only gradually recognized. Gained recognition and understanding of the one-way flow of information from genes to a growing organism. At the scientific level, the Darwinian revolution in the 19th century was not yet complete, and only Mendelian genetics offered a reliable theory of the inheritance of variation. Eventually evolution came to be seen as a change in the relative frequency of genes in populations, but "population thinking" represented a huge shift in conceptual structure that happened quite slowly. The synthesis of population genetics and the theory of evolution was carried out only in the 1930s. With the discovery of DNA in the 1950s. and subsequent development molecular biology evolutionary theory has improved and gone beyond Darwinian ideas (see chapter 9).
TECHNICAL UNIVERSITY
ESSAY
by discipline
"Concepts of modern natural science"
on the topic:
"Alternative evolutionary theories: Lamarckism, catastrophism,
saltationism.
Synthetic theory of evolution"
Performed: student gr. E-118
Yandubaeva Galya
Checked:
1. Alternative evolutionary theories
Lamarckism
The first holistic doctrine of the evolutionary development of living nature, the main ideas of which were outlined by J. B. Lamarck in the "Philosophy of Zoology" (1809).
At the heart of Lamarckism lies the idea of gradation - the internal "striving for perfection" inherent in all living things; the action of this evolutionary factor determines the development of living nature, a gradual but steady increase in the organization of living beings - from the simplest to the most perfect. The result of gradation is the simultaneous existence in nature of organisms of varying degrees of complexity, as if forming a hierarchical ladder of beings. Gradation is easily traced when comparing representatives of large systematic categories of organisms (for example, classes) and on organs of paramount importance. Considering gradation to be a reflection of the main trend in the development of nature, planted by the “supreme creator of all things,” Lamarck tried to give this process a materialistic interpretation: in a number of cases, he associated the complication of organization with the action of fluids (for example, caloric, electricity) penetrating into the body from the external environment. Another factor in evolution, according to Lamarck, is the constant influence of the external environment, which leads to a violation of the correct gradation and determines the formation of the whole variety of adaptations of organisms to environmental conditions. Environmental change is the main cause of speciation; while the environment is unchanged, the species remain constant; if there is a shift in it, the views change. Lamarck consciously distinguished between these factors of evolution, noting that the first of them in the organism correspond to "permanent abilities", the second - "abilities that are subject to change under the influence of circumstances."
The external environment for plants and lower animals, devoid of a differentiated nervous system, act directly, cause adaptive changes in them. Animals with a nervous system are indirectly influenced by the environment, their evolutionary transformations are carried out in a more complex way. Any significant change in external conditions leads to a change in the needs of animals living in the area. Changing needs entails changing habits to meet those needs. Changing habits leads to increased use of some organs and disuse of others. More often, functioning organs are strengthened and developed, while those that are not used weaken and disappear. The resulting functional and morphological changes are inherited, offspring, intensifying from generation to generation. Thus, according to Lamarck, the function plays a leading role in the evolutionary transformations of organisms: a change in form is a consequence of a change in function. The provisions on the exercise and non-exercise of organs and on the inheritance of acquired characteristics were elevated by Lamarck to the rank of universal laws of evolution. The failure of both "laws" was proved experimentally already at the end of the 19th century and especially at the beginning of the 20th century thanks to the discoveries of genetics. In his later works (1815, 1820), Lamarck brings both factors of evolution closer together to a large extent. He is inclined to consider the environment not only as a force that violates the straightness of gradation, but also as the main factor in evolution. Accordingly, he connects the origin of the main branches of the genealogical tree of organisms with the influence of specific conditions of existence.
Justifying his doctrine, Lamarck relied on the following facts:
the presence of varieties that occupy an intermediate position between the two species;
difficulties in diagnosing related species and the presence in nature of many “doubtful species”;
change in species forms during the transition to other ecological and geographical conditions;
cases of hybridization, especially interspecific.
Lamarck also considered important evidence for the transformation of species to be the discovery of fossil forms, changes in animals during domestication and plants when introduced into culture. Developing ideas about evolution, he came to the conclusion that there are no real boundaries between species and to the denial of the very existence of species. The observed gaps in the natural series of organic forms (which makes it possible to classify them) are only apparent violations of a single continuous chain of organisms, due to the incompleteness of our knowledge. Nature, in his opinion, is a continuous series of changing individuals, and taxonomists only artificially, for the sake of convenience of classification, divide this series into separate systematic groups. Such an idea of the fluidity of species forms was in logical connection with the interpretation of development as a process devoid of any breaks and jumps (the so-called flat evolutionism). This understanding of evolution was consistent with the denial of the natural extinction of species: fossil forms, according to Lamarck, did not die out, but, having changed, continue to exist in the guise modern species. The existence of the lowest organisms, as if contradicting the idea of gradation, is explained by their constant spontaneous generation from inanimate matter. According to Lamarck, evolutionary changes usually cannot be directly observed in nature only because they occur very slowly and are incommensurate with the relative brevity of human life.
Lamarck extended the principle of evolution to the origin of man, although under the prevailing creationism he was forced to disguise his beliefs. He believed that man descended from monkeys. Among the factors in the formation of man, he attributed the transition to upright posture and the emergence of speech. Lamarck historically approached the highest manifestations of life activity - consciousness and the human psyche, linking their emergence with the evolution of the nervous system and its higher department - the brain.
Without giving an explanation of organic expediency and without revealing the true cause of evolutionary development, Lamarck for the first time proclaimed the principle of evolution as a universal law of living nature. Throwing down a bold challenge to the then prevailing ideas about the constancy of species, he was one of the first to make the problem of evolution the subject of a special study, a special area of biological research. That is why Lamarck deserved the high appraisal of the classics of Marxism.
Lamarckism did not receive recognition from contemporaries and after the death of its creator was forgotten. The revival of Lamarckism in the form of neo-Lamarckism occurred in the last third of the 19th century as a reaction to the spread of Darwinism.
No other scientific theory is as controversial as the theory of evolution. According to a recent poll, only 15% of people believe that Homo sapiens evolved by chance.
Therefore, even today there are more and more new theories of how mankind has developed and will develop. In our review of the 10 most popular alternative theories of evolution.
1. Intelligent design
The founders of the theory of intelligent design are American mathematician and philosopher Willian Dembski and biochemist Michael Behom.
Some things are too complex to evolve by chance, they argue, so instead of assuming that humans are just a slightly more evolved ape, you should “start looking for the heavenly equivalent of Steve Jobs.”
In other words, life on Earth arose as a result of the intervention of some higher mind.
2. Morphic resonance
While most of the world is arguing about evolution in biology, Rupert Sheldrake decided to look at the origin of species from the point of view of the universe.
According to his theory, over time, invisible morphic fields are formed that contain the collective memory of organisms and substances, including stars and galaxies. This information field influences the subsequent development of similar species.
3.Christian Science
Christian Science is the theory that God is everywhere and everything around him is a part of him. This theory, Mary Baker Eddy argued, is based on the eternal truths contained in the Bible. This theory also states that nothing exists but the spirit, so everything around is an illusion.
4. Cosmic ancestors
The cosmic ancestry theory says that the universe has always existed, and life has always existed in it as well.
On Earth, life arose by being introduced by microbes from outer space. In the future, life evolved, imitating life in the universe.
5 Ancient Astronauts
According to the theory of intelligent design or cosmic heritage, aliens arrived on Earth millions of years ago and purposely gave rise to life here. Ancient texts, flying saucers, pyramids, the Mayan calendar, and so on are cited as evidence.
6. Progressive Creationism
The well-known story from the book of Genesis is that God created the Earth in six days, and rested on the seventh day. Progressive creationists claim that each of these "days" lasted millions of years.
7. Punctuated equilibrium
Of all the theories on this list, the theory of punctuated equilibrium is by far the most mainstream. As you know, all archaeological finds testify not to gradual evolution, but to the sudden appearance of species.
The theory of punctuated equilibrium states that all species are in stable equilibrium, which are interrupted by short periods of strong change.
8. Theistic evolutionism
Theistic evolutionism is the science that most of all combined Darwin's theory and God's creation of man. The idea is that God created the universe and everything in it, only he created everything according to scientific theory.
Therefore, evolution is one of the divine instruments in his experiments with creation.
9. Scientology
The religion, which was created on the basis of the belief system created by the American science fiction writer Ron Hubbard, claims that the human consciousness has gone from birds to sloths, and then monkeys and finally people.
Humans are the product of an alien race that died in a nuclear holocaust millions of years ago, and their consciousness was transferred from one animal to another until it entered the human brain. Feelings such as indecision, envy and toothache remained as a load of animal memories.
10 Creationism
Creationism claims that everything in Genesis is absolutely correct. Literally: God created the Earth and everything that is on it within six days, that we all descended from Noah and once there were giants
In addition, the Earth is only six thousand years old, so any geological and archaeological data is complete nonsense.
The first holistic doctrine of the evolutionary development of living nature, the main ideas of which were presented by Zh.B. Lamarck in The Philosophy of Zoology (1809).
Lamarckism is based on the idea of gradation - the internal "striving for perfection" inherent in all living things; the action of this evolutionary factor determines the development of living nature, a gradual but steady increase in the organization of living beings - from the simplest to the most perfect. The result of gradation is the simultaneous existence in nature of organisms of varying degrees of complexity, as if forming a hierarchical ladder of beings. Gradation is easily traced when comparing representatives of large systematic categories of organisms (for example, classes) and on organs of paramount importance. Considering gradation to be a reflection of the main trend in the development of nature, planted by the “supreme creator of all things,” Lamarck tried to give this process a materialistic interpretation: in a number of cases, he associated the complication of organization with the action of fluids (for example, caloric, electricity) penetrating into the body from the external environment. Another factor in evolution, according to Lamarck, is the constant influence of the external environment, which leads to a violation of the correct gradation and determines the formation of the whole variety of adaptations of organisms to environmental conditions. Environmental change is the main cause of speciation; while the environment is unchanged, the species remain constant; if there is a shift in it, the views change. Lamarck consciously distinguished between these factors of evolution, noting that the first of them in the organism correspond to "permanent abilities", the second - "abilities that are subject to change under the influence of circumstances."
The external environment affects plants and lower animals, devoid of a differentiated nervous system, directly, causing adaptive changes in them. Animals with a nervous system are indirectly influenced by the environment, their evolutionary transformations are carried out in a more complex way. Any significant change in external conditions leads to a change in the needs of animals living in the area. Changing needs entails changing habits to meet those needs. Changing habits leads to increased use of some organs and disuse of others. More often, functioning organs are strengthened and developed, while those that are not used weaken and disappear. The resulting functional and morphological changes are inherited, offspring, intensifying from generation to generation. Thus, according to Lamarck, the function plays a leading role in the evolutionary transformations of organisms: a change in form is a consequence of a change in function. The provisions on the exercise and non-exercise of organs and on the inheritance of acquired characteristics were elevated by Lamarck to the rank of universal laws of evolution. The failure of both "laws" was proved experimentally already at the end of the 19th century and especially at the beginning of the 20th century thanks to the discoveries of genetics. In his later works (1815, 1820), Lamarck brings both factors of evolution closer together to a large extent. He is inclined to consider the environment not only as a force that violates the straightness of gradation, but also as the main factor in evolution. Accordingly, he connects the origin of the main branches of the genealogical tree of organisms with the influence of specific conditions of existence.
Justifying his doctrine, Lamarck relied on the following facts:
Ё the presence of varieties that occupy an intermediate position between the two species;
Difficulties in diagnosing related species and the presence in nature of many "doubtful species";
Ё change in species forms during the transition to other ecological and geographical conditions;
E cases of hybridization, especially interspecific.
Lamarck also considered important evidence for the transformation of species to be the discovery of fossil forms, changes in animals during domestication and plants when introduced into culture. Developing ideas about evolution, he came to the conclusion that there are no real boundaries between species and to the denial of the very existence of species. The observed gaps in the natural series of organic forms (which makes it possible to classify them) are only apparent violations of a single continuous chain of organisms, due to the incompleteness of our knowledge. Nature, in his opinion, is a continuous series of changing individuals, and taxonomists only artificially, for the sake of convenience of classification, divide this series into separate systematic groups. Such an idea of the fluidity of species forms was in logical connection with the interpretation of development as a process devoid of any breaks and jumps (the so-called flat evolutionism). This understanding of evolution was consistent with the denial of the natural extinction of species: fossil forms, according to Lamarck, did not die out, but, having changed, continue to exist in the guise of modern species. The existence of the lowest organisms, as if contradicting the idea of gradation, is explained by their constant spontaneous generation from inanimate matter. According to Lamarck, evolutionary changes usually cannot be directly observed in nature only because they occur very slowly and are incommensurate with the relative brevity of human life.
Lamarck extended the principle of evolution to the origin of man, although under the prevailing creationism he was forced to disguise his beliefs. He believed that man descended from monkeys. Among the factors in the formation of man, he attributed the transition to upright posture and the emergence of speech. Lamarck historically approached the highest manifestations of life activity - consciousness and the human psyche, linking their emergence with the evolution of the nervous system and its higher department - the brain.
Without giving an explanation of organic expediency and without revealing the true cause of evolutionary development, Lamarck for the first time proclaimed the principle of evolution as a universal law of living nature. Throwing down a bold challenge to the then prevailing ideas about the constancy of species, he was one of the first to make the problem of evolution the subject of a special study, a special area of biological research. That is why Lamarck deserved the high appraisal of the classics of Marxism.
Lamarckism did not receive recognition from contemporaries and after the death of its creator was forgotten. The revival of Lamarckism in the form of neo-Lamarckism occurred in the last third of the 19th century as a reaction to the spread of Darwinism.
In about alternative theories of evolution
It turns out that the popularization of scientific knowledge is a dangerous business. Dear mavr_alex says that he almost didn’t get it from his friends. For trying to carry the evolutionary doctrine to the masses. Therefore, I will continue to educate exclusively online. So at least you won't beat
I drew attention to the fact that the myth of Darwin's theory (aka Synthetic Theory, aka Neo-Darwinism) as the only scientific theory of evolution has taken root in society. Like, either old Darwin, or creationism, or aliens, which are about nothing. And everything, the fourth is not given.
But in fact, theories of evolution are pretty fucked up. I will try to briefly talk about the most reasonable and popular today:
Neo-Lamarckism The most beloved, after Marxism-Leninism, of course, is the teaching of Comrade Stalin. There is nothing to say about the fiery Michurinist Trofim Denisovich Lysenko.
Also in early XIX century, the great biologist Jean-Baptiste Lamarck suggested that the qualities that parents acquire through training are somehow transmitted to their offspring. For example, the ancestors of giraffes pulled-pulled their necks up. From this, each new generation was born with a slightly longer neck. And, voila, they turned out such cool giraffes.
In fact, this idea is not as absurd as it seems. There is a hereditary modification variability, which is often adaptive. When a very strong stress acts on a population, genetic changes sometimes occur in it, and offspring in a short time can acquire new qualities that allow them to better survive this stress.
It is not yet clear to what extent this mechanism affects speciation, but modern followers of neo-Lamarckism are sure that it also affects it. However, there are fewer and fewer of them.
Orthogenesis. Well, or nomogenesis. This idea was developed, among other things, by the remarkable Soviet zoologist Lev Semyonovich Berg. Laureate of the Stalin Prize, by the way. The later Frankfurt constructional theory and the modern Theory of Autoevolution by Lima de Faria are very close to his conclusions.
The essence of the idea is that natural selection does not affect anything, hereditary variability obeys certain laws and has a certain direction. There are a limited number of hereditary variations, and they go in certain directions.
Like, evolution is largely a deployment of already existing inclinations, and not a random process, as the Synthetic Theory interprets it. According to nomogenesis, the direction of evolution is generally largely “predetermined” by some initial properties of life.
If neo-Darwinists see the cause of evolution in divergence - the divergence of signs of organisms, then nomogenesis, on the contrary, consider convergence to be the basis of evolution, the process in which different organisms acquire the same signs.
It is clear that both of them have just carloads of supporting material. I won't even give examples, they are obvious.
saltationism. In principle, it is similar to Neo-Darwinism. Only the guys believe that the basis of evolutionary changes is not the accumulation of small mutations and small new traits associated with them. And mutations are large systemic. If saltationists are to be believed, speciation proceeds very rapidly, in just a few generations, and evolution is spasmodic. Accordingly, selection does not operate at the level of intraspecific struggle, as old man Darwin suggested, but at the level of interspecific struggle.