Presentation on the theme "Evolutionary doctrine of Charles Darwin". Presentation for the lesson "Charles Darwin: the main provisions of the theory of speciation" Evolutionary theory of Darwin presentation

Charles Darwin was born in 1809. u Studied at the medical and theological faculties, was going to become a priest. uIn 1831 he embarks on a 5-year voyage on the ship "Beagle" as a naturalist u23 year systematizes factual material uIn 1859 he published the first natural science evolutionary theory.

1859 - "The origin of species by natural selection" The main provisions of the theory of Charles Darwin uOrganisms are changeable. u For evolution, only hereditary (undefined) variability matters. uCauses of evolution: the struggle for existence and natural selection.

The mechanism of evolution (according to the theory of Charles Darwin) The ability of organisms to reproduce indefinitely Limited resources of the environment Hereditary variability Struggle for existence Natural selection The emergence of adaptations The emergence of species The results of evolution

Forms of variability (according to Darwin) u Definite, group, non-hereditary (modern - modification). It is caused by the influence of the external environment. uUndefined, individual, hereditary (modern - mutational). u Relative, correlative - a change in one organ causes a change in others.

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Charles Robert Darwin (1809-1882) - the founder of evolutionary biology. C. Darwin was born on February 12, 1809 in the family of a doctor. While studying at the Universities of Edinburgh and Cambridge, Darwin gained in-depth knowledge of zoology, botany and geology, skills and a taste for field research. The book "Principles of Geology" by the outstanding English geologist Charles Lyell played an important role in the formation of his scientific outlook. In 1854-1855, Darwin began to work closely on the theory of evolution: he collected materials on the variability, heredity and evolution of wild species of animals and plants, as well as data on the methods of breeding domestic animals and cultivated plants, comparing the results of artificial and natural selection. He began to write a book, which, according to his estimates, should have consisted of 3-4 volumes. By the summer of 1858, he had written ten chapters of this work. This work was never completed and was first published in the UK in 1975. In 1859, Darwin published The Origin of Species by Natural Selection, or the Conservation of Favored Breeds in the Struggle for Life, where he named natural selection and indefinite variability as the main driving force of evolution. In 1868, Darwin published his second work, "Changing Domestic Animals and Crop Plants," which included many examples of the evolution of organisms. In 1871, his work "The Descent of Man and Sexual Selection" appeared, where Darwin substantiated the hypothesis of the origin of man from an ape-like ancestor.

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Scientific background E. Kant (1724-1804) in his famous work "General Natural History and Theory of Heaven" rejected the myth of the first shock and came to the conclusion that the Earth and the entire solar system is something that has arisen in time. Thanks to the works of E. Kant, P. Laplace and W. Hertel, the Earth and the Solar System began to be considered not as once created, but as developing in time. In 1830, the English naturalist, founder of historical geology, Charles Lyell (1797-1875) substantiated the idea of ​​the variability of the Earth's surface under the influence of various reasons and laws: climate, water, volcanic forces, organic factors. Lyell expressed the idea that the organic world is gradually changing, and this was confirmed by the results of paleontological studies of the French zoologist J. Cuvier (1769-1832). In the first half of the 19th century. the idea of ​​the unity of all nature was developed. The Swedish chemist I. Berzelius (1779-1848) proved that all animals and plants are composed of the same elements as the bodies of inanimate nature. German chemist F. Wöhler (1800-1882) for the first time in 1824 chemically synthesized oxalic acid in the laboratory, and in 1828 - urea, thus showing that the formation of organic substances is possible without the participation of a certain "vital force" inherent in living organisms.

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Scientific background In the XVIII-XIX centuries. due to the prevailing historical conditions (colonization of vast territories and their research), ideas about the diversity of the organic world, about the patterns of its distribution over the continents of the globe, have significantly expanded. Systematics is developing intensively: all the diversity of the organic world required its classification and reduction into a certain system, which was important for the development of the idea of ​​the kinship of living beings, and then of the unity of their origin. In the first half of the 19th century. a detailed study of the geographical distribution of organisms begins; biogeography and ecology begin to develop, the first generalizing conclusions of which were important for substantiating the idea of ​​evolution. So, in 1807, the German naturalist A. Humboldt (1769-1859) expressed the idea of ​​the dependence of the geographical distribution of organisms on the conditions of existence. The Russian scientist K.F. Roulye (1814-1858) tries to interpret the historical change in the face of the Earth and the conditions of life on it and to explain the influence of these changes on the change in animals and plants. His student N.A. Severtsov (1827-1885) expressed ideas about the relationship of organisms with the environment, about the formation of new species as an adaptive (adaptive) process. Comparative morphology and anatomy are developing. Her successes helped to clarify not only the similarity of the structure of various animal species, but also such a similarity in their organization, which suggested a deep connection between them, about their unity. Comparative embryology is taking shape. In 1817-1818. I. Kh. Pander discovered the germ layers and the versatility of their establishment in animal embryogenesis. The German researcher M. Rathke applied the theory of germ layers to invertebrates (1829). At the end of the 20s of the XIX century. the Russian embryologist K.M.Bair (1792-1870) established the main stages of embryonic development and proved that all vertebrates develop according to a single plan. Subsequently, Baer's generalizations were called by Darwin the law of embryonic similarity and were used by him to prove evolution. A remarkable sign of embryonic similarity is, for example, the presence of gill slits in the walls of the pharynx in the embryos of all vertebrates, including humans. In 1839, the German zoologist T. Schwann created a cell theory, which substantiated the generality of the microstructure and development of animals and plants.

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Socio-economic preconditions A. Smith created the doctrine of "free competition". He believed that the engine of production development is free competition, which is based on the "natural self-interest", or "natural egoism" of a person, which is the source of national wealth. Unadapted competitors are eliminated in the process of free competition. The idea of ​​competitive relations characteristic of the transition from feudalism to capitalism influenced, paradoxically, the formation of ideas about the development of living nature (Charles Darwin subsequently substantiated the idea of ​​competitive relations between living organisms). T. Malthus believed that the human population is growing exponentially, while food production is only in arithmetic. Overpopulation results in a lack of livelihoods. Malthus explains this by the "eternal natural law of nature", believing that its effect can be limited only by a decrease in population. Otherwise, nature itself will restore balance with the help of hunger, disease, etc., sharply increasing the intensity of competition. The idea of ​​overpopulation in living nature, arising as a result of the ability of organisms to reproduce in geometric progression, will be used by Charles Darwin to explain the emergence of the struggle for existence.

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Charles Darwin's voyage around the world Of no small importance for the creation of the evolutionary theory was Ch. Darwin's voyage around the world on the English ship "Beagle" (1831-1836). In connection with the tasks set before the expedition to study the outlines of the shores of South America and other territories, Charles Darwin had the opportunity to make long excursions, to study the geological rocks, flora and fauna of the visited areas. During the trip, he collected numerous facts that testified in favor of the changeability of species and undermined faith in their creation. These facts can be grouped into three groups.

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The first group of facts ... ... testifies to the historical connection between extinct and living animals. Darwin found, for example, a significant similarity of fossil representatives of the fauna of South America with modern sloths and armadillos.

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The second group of facts ... ... refuted the concept of the constancy of species, revealed the regularities of the geographical distribution of animal species. Comparing the fauna of South and North America, Darwin pondered the reasons for their significant difference. There are species in South America (American monkey, llama, tapirs, anteaters, armadillos) that are not found in North America; in turn, the latter contains forms that are absent in South America. In analyzing these facts, Darwin applied the historical method, evaluating the fauna of the Americas in its change, in accordance with its geological past. He believed that originally North and South America were inhabited by similar forms. Later, in connection with the emergence of a vast plateau in the southern part of the Mississippi, the faunas of these continents became isolated. The original species became extinct, and the ones that replaced them, due to isolation, developed in different directions, which led to the difference in the fauna of North and South America.

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The third group of facts ... ... is related to the fauna of the Galapagos Islands. On these volcanic islands, Charles Darwin discovered nowhere else found, but very similar to South American species of finches, mockingbirds, Galapagos buzzards, owls, lizards, turtles, etc. Each island of the Galapagos archipelago has its own form, for example, finches , but all of them, taken together, form one natural group. C. Darwin suggested that all Galapagos finch species apparently descended from one ancestral species that came here from the mainland.

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The main provisions of the evolutionary doctrine 1. Within each species of living organisms, there is a huge range of individual hereditary variability in morphological, physiological, behavioral and any other characteristics. This variability can be continuous, quantitative, or intermittent qualitative, but it always exists. 2. All living organisms multiply exponentially. 3. Vital resources for any kind of living organisms are limited, and therefore there must be a struggle for existence either between individuals of the same species, or between individuals of different species, or with natural conditions. In the concept of "struggle for existence" Darwin included not only the actual struggle of an individual for life, but also the struggle for success in reproduction.

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The main provisions of the evolutionary doctrine 4. Under the conditions of the struggle for existence, the most adapted individuals survive and give offspring, having those deviations that accidentally turned out to be adaptive to the given environmental conditions. This is a fundamentally important point in Darwin's argumentation. Deviations do not arise directionally - in response to the action of the environment, but randomly. Few of them prove to be useful in specific conditions. The descendants of the surviving individual who inherit the beneficial deviation that allowed their ancestor to survive are more adapted to the given environment than other members of the population. 5. Survival and preferential reproduction of adapted individuals Darwin called natural selection. 6. Natural selection of separate isolated varieties in different conditions of existence gradually leads to divergence (divergence) of the characters of these varieties and, ultimately, to speciation.

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Artificial selection preservation and reproduction of specimens of plants and animals, in any respect beneficial or beneficial to people

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Forms of Artificial Selection Unconscious selection is a selection that does not aim at creating a new variety or breed. People keep the best, in their opinion, individuals and destroy (discard) the worst. Unconscious selection arose a long time ago, from the moment of the domestication of the dog. Unconscious selection leads to changes in plants and animals, to the improvement of breeds and varieties, to the creation of new local breeds and varieties. The desired result in this selection is slow to form, but it can be impressive. Methodical selection is a selection carried out by a person according to a specific plan, with a specific purpose - to create a breed or variety. Features: a goal is set: the breeder decides which traits need to be changed and in which direction, that is, the direction of selection is determined (egg production, fleshiness, beautiful comb, beautiful tail, beautiful plumage); a plan for creating a breed (variety) is drawn up: what breeds (varieties) and in what order should be crossed, what types of crossing should be used; special living conditions are created; methodical selection is creativity.

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Material for selection Two main points are involved in changing breeds of domestic animals and plants cultivated by people: VARIABILITY, which provides material for breeding new breeds; HERITAGE - a common property of all living things, thanks to which the characteristics of parents are passed on to offspring * Darwin personally studied all breeds of domestic pigeons available to him and found that they all descended from a wild rock pigeon. From one form, setting special requirements each time when creating a new breed, people received large blowers with high legs, and a small dove - a seagull, and carrier pigeons with their fast flight, and peacock pigeons with a fan-shaped tail, and many others.

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Natural selection has two sides: differential (selective) survival; differential mortality * i.e. natural selection has positive and negative sides. The negative side of natural selection is elimination. The positive side is the preservation of the phenotypes most appropriate to the conditions of the ecosystem at the moment. * Natural selection increases the frequency of these phenotypes, and hence the frequency of the genes that form these phenotypes.

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Comparative characteristics of artificial and natural selection Features of the evolutionary process Evolution of cultural forms Evolution of species in nature Prerequisites and driving forces of evolution Hereditary variability. Artificial selection Hereditary variation. Struggle for existence. Natural selection Rate of evolution Fast (it takes from 8-10 to 20 years to create a variety or breed) Slow (thousands and millions of years) Results Variety of varieties, breeds Variety of species Adaptability Living organisms are adapted to human needs. Forms with less useful properties are discarded. Living organisms are adapted to environmental conditions. Forms with less useful traits are dying out.

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Conclusion Darwin's evolutionary theory fundamentally undermined the metaphysical ideas about the constancy and immutability of species and about their creation by God. This theory became the basis for the further development of the science of the evolution of the organic world, as well as for all biological sciences.

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Evolutionary doctrine of Charles Darwin Biology lesson in grade 11 Teacher: Ivanova O.V.

Preconditions for the emergence of Charles Darwin's teachings Socio-economic Natural sciences Expeditionary material of Charles Darwin

Socio-economic prerequisites: Development of capitalism Demand of industry for raw materials and population for food Development of agriculture Development of breeding

Adam Smith and his theory of free competition under capitalism (the unadapted dies). Thomas Malthus and his article "On Population", which asserts the obligation of "struggle for existence" between rapidly multiplying people due to the slow growth of production of goods.

Natural science prerequisites: Comparative anatomy and morphology: a unified plan for the structure of vertebrates (Goethe, Bronn, Saint-Hilaire) Embryology: the law of embryonic similarity (K. Baer) Cell theory: the unity of the origin of plants and animals Paleontology: fundamentals of geochronology, theory of catastrophes (J. Cuvier ) I. Kant laid the foundations of the concept of the possibility of the evolution of cosmic bodies Geologist C. Lyell developed the theory of the evolution of the Earth

Charles Robert Darwin (1809-1882) English natural scientist, creator of evolutionary doctrine. Darwin studied medicine at the University of Edinburgh (1825-1827), theology at Cambridge (1827-1831), where he received a bachelor's degree. In 1831-1836. makes a round-the-world trip on the ship "Beagle" as a naturalist, from which he returns as a man of science. 1859 "The origin of species by natural selection." 1866 "Change of domestic animals and cultivated plants." 1871 "Human Descent and Sexual Selection"

Charles Darwin's expeditionary material: Paleontological finds: fossils of giant sloths and armadillos Comparison of the fauna of South and North America Analysis of island flora and fauna (Galapagos archipelago): animals came to the islands from the mainland and changed as a result of adaptation to new habitat conditions

The main provisions of the evolutionary teachings of Charles Darwin The variety of species of animals and plants 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 selection is hereditary variability. The stability of the species is ensured by heredity.

The evolution of the organic world predominantly followed the path of complicating the organization of living beings. The adaptability of organisms to environmental conditions is the result of the action of natural selection. Both favorable and unfavorable changes can be inherited. But the "owners" of the latter, as a rule, are destroyed in the struggle for existence.

The variety of modern domestic animal breeds and varieties of agricultural plants is the result of artificial selection. Human evolution is associated with the historical development of ancient apes.

Significance of Charles Darwin's Evolutionary Teachings Regularities of transformation of one organic form into another are revealed. The reasons for the expediency of organic forms are explained. The law of natural selection is discovered. The essence of artificial selection has been clarified. The driving forces of evolution are determined.

Properties of the external environment Properties of organisms Inhomogeneity Limited and uneven distribution of resources Inheritance Variability Intensity of reproduction Struggle for existence Natural selection Diversity of the organic world Different directions of evolution Simultaneous existence of primitive and highly organ-x forms Adaptation to the environment

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Charles Robert Darwin

"The more we learn the immutable laws of nature, the more incredible miracles become for us."

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Charles Darwin

English scientist naturalist and traveler One of the first to realize and clearly demonstrated that all types of living organisms evolve in time from common ancestors In his theory, the main driving force of evolution Darwin called natural selection and indefinite variability Darwin's ideas and discoveries form the foundation of the modern theory of evolution and form the basis biology

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Biography

Born February 12, 1809 in Shrewsbury Father - Robert Darwin, son of the famous poet and scientist Erasmus Darwin

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1827 - studied theology at the University of Cambridge for three years. 1831 - after graduating from the university, he went on a round-the-world voyage on the expeditionary ship of the Royal Navy "Beagle". During the trip, Darwin visited the Cape Verde Islands, the coast of Brazil, Argentina, Uruguay, Tierra del Fuego, Tasmania and the Cocos Islands and made a large number of observations. The results were presented in the Proceedings Diary of Research, Zoology of travel on the ship "Beagle", The structure and distribution of coral reefs, etc.

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Travel on the Royal Navy Expeditionary Ship "Beagle"