Charles Darwin was born in 1809. uHe studied at the medical and theological faculties, he was going to become a priest. uIn 1831, he went on a 5-year voyage on the ship Beagle as a naturalist.
1859 - "The Origin of Species by natural selection» The main provisions of the theory of Ch. Darwin uOrganisms are changeable. uFor evolution, only hereditary (indeterminate) variability matters. uCauses of evolution: the struggle for existence and natural selection.
The mechanism of evolution (according to the theory of Ch.Darwin) The ability of organisms to unlimited reproduction The limited resources of the environment Hereditary variability The struggle for existence Natural selection The emergence of adaptations The emergence of species The results of evolution
Forms of variability (according to Darwin) u Defined, group, non-hereditary (modern - modification). Caused by the influence of the external environment. uIndefinite, individual, hereditary (modern - mutational). u Correlative, correlative - a change in one organ causes a change in others.
Presentation " evolutionary theory Charles Darwin" considers this topic in the section "Evolutionary Teaching" in grades 9 and 11. Introduces the driving forces of evolution, characterizes the types of struggle for existence, compares artificial and natural selection.
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Ch. Darwin's evolutionary theory The struggle for existence is intraspecific; - interspecies; - with adverse environmental conditions Natural selection Survival of the fittest and death of the least fit Driving forces of evolution Based on hereditary variability
Natural selection Natural selection is understood as the process of conservation and predominant reproduction in nature in a number of generations of individuals that have adaptive traits useful for their life and development, resulting from the multidirectional individual variability Ch. Darwin gave a definition of natural selection: “The preservation of useful differences or changes and the destruction of the harmful I have called natural selection, or the survival of the fittest."
"Darwin's theory of evolution" CAUSES MECHANISMS WITH CONSEQUENCE The desire of organisms for unlimited reproduction Limitation of habitat resources STRUGGLE FOR EXISTENCE NATURAL SELECTION HEREDITARY VARIABILITY Relative adaptation of organisms to the environment DIVERSITY OF SPECIES IN NATURE PROGRESSIVE CHARACTER OF EVOLUTION
The main provisions of Darwin's teachings 1. Thanks to hereditary variability, organisms of the same species differ from each other in many hereditary characteristics. 2. Organisms multiply exponentially. Life resources are limited. This leads to a struggle for existence. 3. The result of the struggle for existence is a natural struggle. With natural selection, individuals that are most adapted to changing environmental conditions survive and individuals with inadequate changes are eliminated. 4. Surviving individuals give rise to a new generation, thus "successful" changes are inherited. With the long-term action of natural selection, after many generations, individuals can differ significantly from the original forms, a new species is formed.
Comparative characteristics of natural and artificial selection Indicators Artificial Natural Source material for selection Individual characteristics of the organism Individual characteristics of the organism Selecting factor Man Environmental conditions (living and inanimate nature) Criteria Usefulness of the trait for humans Adaptation of the species to environmental conditions
Indicators Artificial Natural Source of genetic diversity Hereditary variability. Artificial mutations, crossing, etc. Hereditary variability. Natural Mutations Timing Relative short time Long period of time Result New varieties of plants, breeds of animals, strains of microorganisms. Often leads to the appearance of species not possible in nature (cabbage-rare) New species
Indicators Artificial Natural Forms of selection Mass, individual, unconscious, methodical (conscious) Driving, stabilizing, Disruptive Significance for evolution As a result of the interaction of domestic animals, cultivated plants and wildlife, the emergence of new species based on artificially bred breeds and varieties is possible. It is the guiding factor of evolution, plays a leading role in the emergence of the Diversity of the organic World.
Indicators Artificial Natural Significance of acquired traits for organisms May be harmful to the organisms themselves. The main indicator is significance for humans Increase the adaptability of organisms to environmental conditions
evolutionary doctrine
Ch. Darwin.
Evidence for evolution
Teacher Smirnova Z. M.
Creation of evolutionary theory
Teaching created
Ch. Darwin and A. Wallace
1858 – On July 1, at the Meeting of the Linnean Society, the concepts of Charles Darwin and A. Wallace on the emergence of species through natural selection were presented.
1859 - The first edition of the book "The Origin of Species by Means of Natural Selection"
Charles Darwin
1809-1882
Alfred Wallace
(1823-1913)
Prerequisites for the emergence of the theory
Ch. Darwin
Socio-economic:
1. Development of capitalism (search for markets, sources of raw materials);
- Organization of round-the-world trips, participation
Ch. Darwin
3. The practice of breeders: the creation of animal breeds and plant varieties.
Scientific background:
1. Cellular structure of organisms (R. Hooke, A. Levenguk);
2. The similarity of animal embryos (K. Baer);
3. Discoveries in the field of comparative anatomy of paleontology (J. Cuvier);
4. Geologist C. Lyell proved that the earth's surface is constantly changing under the influence of natural processes (t, wind, precipitation, etc.).
"Beagle"
Charles Lyell (1797-1875)
Creation of evolutionary theory
The main merit of Charles Darwin is that he revealed the driving forces of evolution. He materialistically explained the emergence and relative nature of fitness by the action of natural laws only, without the intervention of supernatural forces.
Darwin's teaching fundamentally undermined metaphysical ideas about the constancy of species and their creation by God.
The practice of agriculture served as a model for the processes occurring in nature for Darwin.
in England.
Driving forces for the evolution of varieties and breeds
Variation: Artificial selection
– indefinite
(genotypic); Conscious Unconscious
– certain - held in – man is not
(modification); accordance with puts before
– correlative self-imposed goal, and
(correlative) purpose, simply eliminates
scheduled less valuable
individual breeder and leaves
the best in the tribe
The selection produced by man is called artificial.
Artificial selection - directed accumulation of traits
for the benefit of man.
The result of selection work
Savoy
white-headed
Krasnokochannaya
wild cabbage
Kohlrabi
color
Beijing
Broccoli
Brussels
Formation of new species in natural conditions
The study of artificial selection helped Charles Darwin to understand the driving forces behind the formation of species in natural conditions:
All beings have a certain level of individual variability;
Traits from parents are passed on to offspring;
Each type of organism is capable of unlimited (in a poppy box there are 3000 seeds, a sturgeon spawns 2 million seeds). eggs);
Lack of vital resources leads to a struggle for existence;
In the struggle for existence, the most survive
individuals adapted to these conditions.
Drivers of Species Evolution
Natural selection -
Hereditary variability:
main, guiding factor of evolution
combinative,
mutational
Struggle for existence
Interspecies
– occurs between
individuals
other types that have
same needs
Intraspecific
– occurs between
individuals of the same species for territory, food, female
Fight against adverse environmental conditions - the strongest and most enduring individuals survive in the fight against drought, flood, cold
result
Darwinian concept of natural selection
The material for evolution is indeterminate variability;
Natural selection is the result of the struggle for existence, selective destruction of some individuals and preferential reproduction of others, most adapted to the environment.
Struggle for existence
Natural selection
consequence
Fitness organisms to environment, variety of species
Forms of natural selection
Natural selection is the only creative factor evolution, directing random hereditary changes along the path of the formation of adaptations.
Forms of natural selection
Moving
selection
Disruptive (tearing)
stabilizing
Forms of natural selection - motive selection
Driving selection - acts in changing environmental conditions and contributes to a shift in the average value of the trait and the emergence of new forms.
Forms of natural selection - stabilizing selection
Stabilizing - valid in constant conditions environment.
Selection is directed against extreme variants and favors individuals with average trait values.
In insect pollinated plants, the size and shape of the flower are stable. Flowers that do not correspond to the structure of pollinating insects do not form seeds, therefore, the genes that caused the deviation from the norm are eliminated from the gene pool of the population. This form selection is described by I. Schmalhausen (1946).
Forms of natural selection - disruptive (tearing) selection
Disruptive (tearing) - operates in a territory with a variety of conditions of existence. It is aimed at selecting not one trait, but several different ones, each of which favors survival. The mean value of the feature is eliminated.
seeds
Leaves
Kidneys/fruits
Larvae
Comparison of artificial and natural selection
Peculiarities
artificial selection
Selection material
Natural selection
Hereditary and non-hereditary variability
Selects
hereditary variability
Human
Result
Environmental conditions
Individuals with valuable traits for humans
are selected
The fittest individuals
New varieties and breeds
new species,
adaptation to environmental conditions
Fitness of organisms
to the environment
According to Lamarck: the driving force behind evolution is the striving of organisms for perfection.
Example: giraffes, when getting food, had to constantly stretch their necks in order to reach the leaves of tall trees (exercise). The trait is inherited.
According to Darwin: among giraffes there were animals with necks of different lengths. Those with slightly longer necks were more successful at foraging and surviving. This trait was inherited. So, gradually, a long
giraffe neck.
The relative nature of the fitness of species
Ch. Darwin's position - fitness (expediency) always has a relative character.
Any adaptation is useful only under the conditions in which it arose; when conditions change, it ceases to be useful or even becomes harmful to the body (a hare, invisible to predators in the snow, is clearly visible against the background of tree trunks and dark earth in a snowless winter).
Device forms
- Morphological adaptations - structural changes
body (streamlined body shape in fish and birds).
- disguise - body shape and coloring merge with surrounding objects (seahorse, stick insects)
Device forms
- Protective coloring - developed in species that live openly and may be available to enemies (flounder, grasshopper). If the background of the environment is not constant depending on the season of the year, the animals change their color (hare, white hare).
Device forms
- Warning color - bright, characteristic of poisonous and stinging forms (wasps, bumblebees, rattlesnakes).
Mimicry - similarity in color, body shape of unprotected organisms with protected ones (fly hoverfly).
Deadly Texas Coral Snake
Harmless Mexican milk snake
Evidence for evolution
- Morphological (comparative anatomy);
- Embryological;
- paleontological;
- Biochemical;
- Biogeographic;
- Molecular genetic evidence
Morphological evidence
(comparative anatomy)
General plan of the structure of vertebrates
Analogous and homologous organs
Rudiments
and atavisms
- The general plan of the structure of vertebrates:
- bilateral symmetry of the body,
- spine,
- secondary body cavity
- nervous
- circulatory, etc.;
Evidence for evolution
Comparative anatomy
- Homologous Organs – similar in structure and origin, regardless of the function performed (the skeleton of the forelimb of vertebrates).
Homologous Organs
Man Cat Whale Flying
mouse
Evidence for evolution
Comparative anatomy
- Similar bodies have different structure and origin, but perform the same functions (gills of fish and crayfish; wings of a bird and a butterfly). Similar organs are the result of convergence.
Similar bodies
mole bear
butterfly wing
bird wing
Evidence for evolution
Comparative anatomy
- Rudiments - disappearing organs, which in the process of evolution have lost their importance for the preservation of the species (the first and third fingers in birds in the wing, the second and fourth fingers in the horse, the pelvic bones in the whale);
Rudiment
megatelny
membranes
ear
muscles
Coccyx
Evidence for evolution
Comparative anatomy
- Atavisms - the appearance in modern organisms of signs of ancestors (highly developed hairline, multi-faciality in humans).
- K. Baer (1828), comparing embryos of different classes, formulated the "law of germinal similarity":
In the early stages of development, the embryos of different groups of vertebrates are similar to each other.
Embryological evidence
F. Müller and E. Haeckel(1866) formulated a biogenetic law on this discovery: ontogenesis (individual development of organisms) repeats phylogenesis (historical evolutionary development of a group).
A. N. Severtsev clarified that in the individual
development, the development of non-adults is repeated
stages, but embryonic.
allow us to describe the events of ancient history
on fossil remains of organisms.
Paleontological evidence for evolution
Transitional forms -
organisms occupying an intermediate position between large systematic groups
fossil remains - remains and traces
vital activity of organisms
past geological epochs.
Phylogenetic series - rows of sequentially replacing each other species.
Fossils
fossil remains - the basis for restoring the appearance of ancient organisms. The similarity of fossils and modern organisms is proof of their relationship. The antiquity of fossil remains is established by the age of the rocks,
in which they are found.
The distribution of ancient, primitive organisms in the deepest layers of the earth's crust, and highly organized -
in later layers
paleontological evidence
Fossil transitional forms
– evidence of successive relationships between different groups of organisms, combine features of older and younger groups.
For example, a transitional form from reptiles to birds is the Jurassic first bird - Archeopteryx the size of a dove, with a long, reptile-like tail and developed teeth. His body was covered with feathers, and his forelimbs turned into wings.
Stegocephalus -
transitional form between lobe-finned fishes and amphibians
paleontological evidence
contemporary
horse
Phylogenetic series of the horse
The evolution of horses is well-documented by fossils, which show how the small, dog-sized forest animal Eohippus, which had fingers instead of hooves, developed over 50 million years into large hoofed inhabitants of open spaces.
hipparion
merykhippus
mesogippus
eohippus
horse's predecessor
Phylogenetic series:
Cetacean Human
Biogeographic
evidence for evolution
The distribution of animals and plants over the surface of the Earth reflects the process of evolution.
Wallace divided the surface of the earth into 6 zoogeographic zones:
- Holarctic zone (North America);
- Ethiopian (Central and South Africa);
- Australian (Australia, Tasmania, New Zealand);
- Indo-Malay (India);
- neotropical (South and Central America).
Biogeographic
evidence for evolution
The closer the connection of the continents, the more related species live on them, the older the isolation, the greater the differences between animals and plants. The most peculiar fauna of the Australian zone.
Molecular genetic
evidence for evolution
All living organisms consist of cells, have a universal genetic code, common mechanisms for storing, implementing and transmitting genetic information.
The 2nd human chromosome is a product of the fusion of two simian ones, and the striation of all chromosomes in both species is very close. Such insignificant differences in the structure of the karyotype usually characterize extremely close species.
Comparison of chromosome sets
human (left) and chimpanzee (right)
Biography of Charles Darwin gg. - studies medicine in Edinburgh; gg.-studies medicine in Edinburgh; gg.-journey on the ship "Beagle"; gg.-journey on the ship "Beagle"; 1837-becomes a convinced evolutionist 1837-becomes a convinced evolutionist and begins to look for the driving factor of evolution; 1839 - publishes descriptions of the journey; 1839 - publishes descriptions of the journey; 1858 - the year of birth of evolutionary theory; 1858 - the year of birth of evolutionary theory; 1971 “The origin of man and sexual selection”. 1971 “The origin of man and sexual selection”.
Between individuals there is a "struggle for existence" The result of the struggle for existence is "natural selection" The result of natural selection: - adaptation of organisms to specific conditions of existence; - Diversity of species inhabiting the Earth.
The value of the teachings of Ch. Darwin Revealed the driving forces of evolution; Revealed the driving forces of evolution; Explain the adaptation of living organisms to external environment and its relative nature. He explained the emergence of adaptability of living organisms to the environment and its relative nature.
DARWIN AND THE THEORY OF EVOLUTION
Chemistry and biology teacher
Lepeshenko Tatyana Ivanovna
GBOU NPO RO PU No. 61
Novoshakhtinsk, Rostov region
The purpose of the lesson:
Consider the theory of evolution of Charles Darwin as a holistic teaching; form an idea of the main provisions evolutionary doctrine Charles Darwin.
Updating of basic knowledge
Why in the 19th century became possible
creation and justification
evolutionary doctrine?
Choose the correct answer: option 1 - J.B. Lamarck option 2 - K. Linnaeus
- Created the first natural classification
- He believed that species exist and do not change
- Created the best artificial system
- Fixed the use of binary nomenclature for the view
- Created the first evolutionary theory
- Described over 8,000 species
- Put before science 3 questions
8. The reason for evolution was the desire of organisms to improve
9. Believed that acquired traits are inherited
10. Made a great contribution to the development of science.
Compose a cinquain about K. Linnaeus,
J.B. Lamarque
C. Darwin
"The Origin of Species by Natural Selection or the preservation of favorable breeds in the struggle for life"
Charles Darwin
Place of Birth: Shrewsbury, England
A place of death: Down, England
Scientific area: Biology, Geology, Paleontology
Place of work: Royal geographical society
Naturalist's Journey on the Beagle 1831-1836
Captain Robert Fitz Roy
Darwin's handwritten diary
Fundamentals of Darwin's evolutionary theory.
The diversity of animal and plant species is the result of historical development organic world.
The main driving forces of evolution are the struggle for existence and natural selection. The selection material provides variability. The stability of the species is ensured by heredity.
The role of natural selection in the formation of adaptations
The evolution of the organic world mainly followed the path of complicating the organization of living beings.
Convergent evolution: development of adaptations for soaring in the air in vertebrates.
The main scientific works of Darwin
- 1839 - A naturalist's journey around the world on the ship "Beagle"
- 1842 – Zoology of travel – (participation in a multi-volume monograph)
- 1851-54 – barnacles
- 1859 - The origin of species...
- 1862 - Pollination in orchids
- 1868 – Variability of animals and plants in the domesticated state
- 1871 – The origin of man and sexual selection
- 1872 – Expression of emotions in humans and animals
- 1876 - The action of cross-pollination and self-pollination in the plant world.
Consolidation of knowledge
The essence of the Darwinian concept of evolution is reduced to a number of logical, experimentally verified and confirmed a huge number actual provisions. Was Darwin the first and only?
Answer
In 1858, the young English scientist Alfred Wallace sent Darwin the manuscript of his paper "On the tendency of varieties to deviate indefinitely from the original type." This article contained an exposition of the idea of the origin of species through natural selection.
The value of evolutionary theory.
- 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 has been discovered.
- The essence of artificial selection is revealed.
- The driving forces of evolution are determined.
Question
Today, Darwin's teachings are recognized by many scientists. Do you agree with them?
Summing up the lesson
- What provisions of the theory of evolution make you feel unproven, disagree, doubt?
- How do you yourself assess the reason for your attitude to this theory?
Homework
- The answer to the question in the form of a message: What is the significance of Mendel's laws for understanding the mechanism of evolution?
- Prepare a message and presentation on the topic “Darwin and the round-the-world trip on the Beagle”.
- Page 153 - 159 Textbook "Biology" for NGOs and SPO V.M. Konstantinov et al. M., Academy, 2014.
- Answer questions 1 - 7 p. 159 of the textbook.
