Presentation of the concept of microevolution and macroevolution. Presentation for the lesson "Micro- and macroevolution
Macroevolution - the evolution of large systematic groups (superspecific rank)
Result
Class Squad
Directions of evolution
In 1925 a Russian zoologist Alexey Nikolaevich Severtsov(1866-1936) developed the doctrine of the main directions of evolution;
In 1934 a Russian biologist
Ivan Ivanovich Schmalhausen(1884-1963) clarified and supplemented the doctrine developed by A. N. Severtsov on the main directions of evolution - biological progress and biological regression.
Main
directions
Biological
regression
Biological
progress
Biological regression -
Decreased fitness level.
Signs:
- Decrease in the number of individuals;
- Decreased range area;
- fade out
Reduced fitness of organisms
to environmental conditions
Activity
human
Factors inanimate
nature
- Extinction of species due to global climate change
- Extinction of species due to human fault
Species extinct due to global climate change
woolly rhinoceros
Saber-toothed tiger
Species exterminated by man
Passenger pigeon
Endangered species
Muskrat
steppe eagle
Spoonbill
Bustard
Apollo
Biological progress -
Increasing the level of fitness.
Signs:
- An increase in the number of individuals;
- Range expansion;
- The formation of new populations
subspecies and species.
Ways to achieve
biological progress
Aromorphosis
General
degeneration
Idioadaptation
Aromorphosis (arogenesis)
- a major transformation of organisms that increases the overall level of organization makes it possible to expand the use of conditions external environment(new food sources, new habitats).
Examples :
- cell formation;
- The emergence of multicellularity;
- The emergence of a flower
- The emergence of photosynthesis, etc.
zander jaws
Aromorphoses provide the transition from passive to active nutrition (appearance of jaws in vertebrates),
Perch skeleton.
increase the mobility of animals (the appearance of the skeleton as a place of attachment of muscles,
Insects.
replacement of layers of smooth muscle in worms with bundles of striated muscle in arthropods),
respiratory function (appearance of gills and lungs),
Fish gills.
Idioadaptation (allogenesis)
- particular adaptations of organisms to specific environmental conditions. (The overall organization level does not change.)
allomorphoses, or idioadaptation - these are anatomical and morphological adaptations that ensure adaptability to certain living conditions
At the same time, organisms do not experience any significant complication or simplification of the level of organization: some organs differentiate further, others lose their significance and are reduced.
Accordingly, the energy of vital activity remains at the same level.
- At the same time, organisms do not experience any significant complication or simplification of the level of organization: some organs differentiate further, others lose their significance and are reduced. Accordingly, the energy of vital activity remains at the same level.
http://chamaeleon.ru/
Since each species of organisms lives in certain places, it develops adaptations precisely to these conditions. Idioadaptations include the protective coloration of animals,
plant thorns,
Species: Mammillaria mazatlanensis K. Schumann ex Gurke 1901
flounder fish
flat body shape of stingrays and flounders.
Depending on the living conditions and lifestyle, the five-fingered limb of mammals undergoes numerous transformations. Consider how diverse are the forms of the limbs of one order of insectivores: the jumper, the burrowing mole,
american jumper
http://www.ekoset.ru/catalog/krot
Similarly, the differences appearance and details of the structure of animals belonging to the order of artiodactyls are caused by the unequal conditions of their existence.
Hippo and Hippo at Patan Zoo
The extreme degree of adaptation to very limited conditions of existence is called specialization. The transition to eating only one type of food, living in a very homogeneous and constant environment (for example, in caves) leads to the fact that organisms cannot live outside these conditions. Such are the hummingbirds, feeding only on the nectar of tropical flowers,
nepenthes
Venus flytrap
carnivorous plants
It is not always possible to draw a clear distinction between aromorphoses and allomorphoses.
For example, the appearance
- fish scales
- feather cover in birds,
- coat in mammals
- - scales in fish, - feather cover in birds, - coat in mammals
can be considered both as partial aromorphoses and as very large allomorphoses (idioadaptation)
General degeneration (catagenesis)
- simplification of organisms in structure and functioning. (The overall level of organization goes down.)
Examples :
digestive system;
- The transition from oxygen respiration to
anoxic;
and leaves, etc.
Bull tapeworm
Tapeworm
In animals, such as tapeworms, the sense organs, the digestive system are reduced, and the structure of the nervous system is simplified. Instead, they develop various private adaptations - suckers, trailers, which help to retain the host in the intestines.
The transition to a sedentary lifestyle and passive feeding (for example, sea squirt) is accompanied by a simplification of organization and elimination from competition with other species, which also leads to the conservation of the species.
Ascidia
Aromorphoses
Aromorphoses
Idioadaptation
Idioadaptation
Idioadaptation
Degeneration
Scheme of relationships between different paths of evolution
Directions of evolution
Aromorphosis
Idioadaptation
Complication of organisms:
- The appearance of the nucleus in the cell;
- The emergence of multicellularity;
- The appearance of a flower.
Adaptations of organisms:
- The appearance of spines in a cactus;
- The appearance of a flat body in flounder;
- Bright color of flowers.
Degeneration
Simplifying organisms:
- Loss of legs in snakes;
- The disappearance of the eyes of the mole;
- Hair loss in humans.
Determine the direction of evolution in each case
- The appearance of the nuclear membrane;
- Loss of the digestive organs
bull tapeworm;
- The emergence of sexual reproduction;
- The emergence of powerful legs with
large claws in birds of prey;
- The emergence of flower adaptability
for pollination by insects.
Slide 2: 1. Population gene pool. Frequencies of genes and genotypes. Hardy-Weinberg law
2 1. Population gene pool. Frequencies of genes and genotypes. Hardy-Weinberg law. A population is an elementary unit of evolution. Evolution operates on groups of organisms, not individuals. It is not the individual that evolves, but the groups of individuals that make up the population. The gene pool is the totality of all genes in all their allelic forms in the gametes of the organisms that make up the population. The gene pool of a species is made up of the gene pool of populations. In the case of an individual diploid organism, the frequency of an allele may be 100%, 50%, or 0%, but in a population, the frequency of a given allele is the percentage of individuals who have that gene. (May range from 0 to 100%).
slide 3
3 In 1908, G. Hardy and W. Weinberg showed that in populations, the frequencies of genotypes and alleles in generations remain constant if such factors as selective marriages, mutations, selection and gene drift do not influence their equilibrium.
slide 4
4 Under conditions of free crossing, the frequency with which two alleles can meet in a diploid organism is equal to the product of the frequencies of each allele. If the relative frequency of the dominant allele A in a two-allelic system is denoted by p, and the relative frequency of the recessive allele a is denoted by q, and if p + q \u003d 1, then with free crossing the frequencies of the three genotypes will be: AA \u003d p 2, Aa \u003d 2 pq, aa \u003d q2.
slide 5
5 For example, one in 10,000 people is albino (the albinism gene is recessive, and the albino is homozygous for the recessive gene). Homozygous genotype frequency: q2 = 1/10,000 = 0.0001; albinism allele frequency q = √0.0001 = 0.01, or 1% Since p + q = 1, the frequency of the dominant allele in the population is 0.99, or 99%. The frequency of the heterozygous genotype is 2 pq = 2 x 0.99 x 0.01 = 0.0198. That is, approximately 2% of individuals in a given population carry the albinism allele either in a heterozygous or homozygous state. Therefore, the frequency of the recessive allele in the population is quite high with a small number of individuals expressing the trait. Heterozygous individuals are called carriers.
Slide 6: 2. The struggle for existence and the factors of evolution
Slide 7
7 2. Intraspecific BZS: in individuals of the same species, the needs for food, territory and other conditions of existence are the same. Therefore, the competition between them is the most intense. (Competition for nesting territory among birds, sexual selection during the breeding season, etc.) 3. Fight against adverse environmental conditions.
Slide 8
8 Factors of evolution: Mutation process. non-directional factor. Maintain the genetic heterogeneity of natural populations. Supplier of elemental evolutionary material. Population waves (waves of life) - fluctuations in the number of individuals in a population in one direction or another from medium size. Evolutionary significance: dramatically change the frequency of alleles and genotypes rarely found in populations. Recombination of genes (see combinative variability).
Slide 9
9 Isolation provides barriers to prevent panmixia (free crossbreeding). Migrations are the movements of individuals carrying alleles and genotypes to or from other populations and their participation in panmixia. Genetic drift is a random, unpredictable change in the frequency of genes in populations that does not depend on natural selection (small population sizes → incomplete representation of possible allele variants, random death of individuals, etc.). It can lead to both the disappearance of the allele and the emergence of new species in island and other reproductively isolated populations. May decrease or increase variability within the species as a whole.
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Slide 10
10 Macroevolution Macroevolution is the process of formation of supraspecific taxa.
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slide 11
11 Paths of evolution How did the organization of living beings become more complicated in the course of evolution? Natural selection as a guiding factor determines the path of evolution. Russian scientist-evolutionist A.N. Severtsov established the following evolutionary paths: aromorphosis, idioadaptation, degeneration. At the macro level, such regularities as divergence (divergence of features in related forms that cause the appearance of homologous organs) and convergence (convergence of features in unrelated organisms, but having similar adaptations to the environment - similar organs) are manifested.
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slide 12
12 Directions of evolution Aromorphoses are evolutionary changes leading to a qualitatively new level of organization: a) makes it possible to move to a new environment; b) contributes to the expansion of the population and its habitat; c) new large taxonomic units arise: types (divisions), classes. .
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Slide 13: Aromorphoses
13 Aromorphoses Multicellularity (growth flagellates) Eukaryotic cell; Autotrophy.
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Slide 14: Aromorphoses
14 Aromorphoses At the phylum level: the appearance of striated muscle bundles in arthropods At the class level: the appearance of a five-rayed limb in amphibians, reptiles and warm-blooded
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slide 15
15 Aromorphosis: improvement of parts of the brain.
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slide 16
16 At the class level: 4-chamber heart of birds, warm-bloodedness Evolution of the heart of vertebrates. 1-two-chamber heart of fish; 2-three-chamber frog heart; 3-chambered heart of a reptile. with an incomplete septum in the ventricle; 4-four-chamber mammalian heart: P-atrium; W-ventricle
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Slide 17
17 Idioadaptation - small evolutionary changes, expressed in adaptation to environmental conditions of habitat: A) there is no increase in the level of organization; B) small taxonomic groups are formed: species, genera, families; C) there are private changes in the structure and functions of organs (adaptation); D) small useful adaptations to the environment lead to the division of a group of organisms into different branches, but a change in the class of organisms does not occur.
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Slide 18
18 scoops moth on stones Examples: protective coloration (under the environment) - a form of passive protection
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Slide 19
19 Warning coloration (1) - bright, unmasking. It is characteristic of poisonous or well-armed insects (for example, a ladybug). Mimicry (2) - imitation, consisting in the similarity of a defenseless or edible species with one or more unrelated species that are well protected and have a warning color (eg flies imitate wasps, etc.). 12
20
Slide 20
20 Coevolution (adaptive adaptations) - joint evolution of the structure of flowers and pollinating insects
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slide 21
21 Variations in the standing of homologous organs - flippers in marine mammals, the variety of beak shapes in Hawaiian flower girls, etc.
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slide 22
23
slide 23
slide 2
Macroevolution: plot marking
- extreme points, which outline the circle of macroevolutionary processes:
- Aramorphosis - idioadaptation
- Divergence - Parallelism - Convergence
- Progress-Regress
- ...and a huge number of synonymous or insertion terms that make the markup more detailed, more descriptive, but do not explain anything.
- Aramorphosis, parallelism, etc. are not a cause, but a statement.
- And what?
slide 3
Macroevolution - site marking
- The study of paleontological finds and modern forms allows us to consider the existence of two main types of evolutionary development groups (Lamark, 1809, Haeckel, 1866; and others): the emergence of a large number of closely related forms that differ in adaptations of the same scale, and development with access to another adaptive zone due to the acquisition by the group of some fundamentally different adaptations that allow going beyond the boundaries of the former adaptive zones.
- Adaptive radiation of the same scale is designated differently in modern evolutionary literature (idioadaptation, allomorphosis, allogenesis, cladogenesis, etc.). To use unambiguous terms, it is advisable to dwell on one of these terms; one of the most suitable seems to be the term "allogenesis" (Paramonov, 1966). To describe the development of a group on the way to a different adaptive zone, the acquisition of evolutionary adaptations greater value the terms "aromorphosis" and "anagenesis" were used. ... we, following A. L. Takhtadzhyan (1966), use the term "arogenesis" for such transformations of the group.
- (From Timofeev-Resovsky and others)
- Aramorphosis according to A.N. Severtsov does not have a clear definition. It is usually set graphically.
slide 4
- Evolutionary transformations that significantly increase the adaptive capacity of this group (allowing you to expand the old or occupy a new adaptive zone), have a significant impact on the organism as a whole, but do not change the overall level of organization, were called epectomorphoses. …Epectomorphoses persist long time during subsequent adaptive radiation, becoming signs of large taxa
- Schmalhausen suggested calling regressive changes catamorphoses, and replacing the term "idioadaptation" with allomorphoses.
- were proposed ... new names for the three main directions of the evolutionary process: morphophysiological progress began to be called arogenesis (or anagenesis), morphophysiological regression - catagenesis, the development of particular adaptations - allogenesis or cladogenesis
- Scheme of the main directions of the evolutionary process:
- A - arogenesis, AL - allogenesis, K - catagenesis, E - epictogenesis
- Planes represent different levels of organization
- From Jordanian
slide 5
- A. N. Severtsov called the evolutionary transformations of the organization, leading to morphophysiological progress, aromorphoses. According to A. N. Severtsov, aromorphoses are such changes in the structure and functions of organs that are of general importance for the organism as a whole and raise the energy of its vital activity to a new qualitative level.
- Thus, the undoubted aromorphoses in the evolution of vertebrates were: the development of the mechanism of active gill ventilation (gill pump) in the most ancient vertebrates through movements of the visceral gill skeleton, the acquisition of the jaw apparatus (with restructuring of the anterior gill arches), the intensification of gill ventilation during the development of the gill cover in bone fish, the acquisition by the latter of a swim bladder - a hydrostatic apparatus that allows fish to regulate their buoyancy; the development in the ancestors of higher terrestrial vertebrates - amniotes of embryonic membranes (amnion, serosa, allantois), which provide the possibility of laying eggs on land; the development of a powerful suction (rarefying) respiratory pump of the chest in reptiles; formation aircraft in birds; development of live birth and feeding of young with milk in mammals; improvement of the brain in birds, mammals and humans.
- Aromorphoses have a very high general adaptive value, increasing the body's independence from the external environment.
slide 6
- Upper and lower jaws and teeth of various snakes
- 1 - python, 2.7 - smooth-toothed already-shaped, 3, 8 - back-furrowed already-shaped, 4,5,9 - slate, 6, 10 - viper
- Skullviper Rhinoceros
- Modifications of the skull of snakes - an example of epectogenesis
- A free, movable, rotating upper jaw and a free, downwardly shifting lower jaw - an epectomorphosis that allowed snakes
- switch from eating insects (the food spectrum of legless lizards) to hunting vertebrates. The general level of vital activity (energy exchange) remains the same.
- Video
Slide 8
- Divergence (from medieval Latin divergo - I deviate)
- The wolverine feeds mainly on carrion. Wide paws with webbing between the fingers help her to move on loose snow in the northern taiga and forest tundra. Weight about 15 kg.
- Weasel is the smallest of mustelids. She is able to penetrate mouse holes. It feeds mainly on mice.
- The badger is omnivorous, active in the warm season, hibernating in the northern part of its range in winter. It builds very complex burrows in which it spends most of its time. Weight about 15 kg.
- Divergence within the mustelid family
Slide 9
- Convergence is not the exact opposite of divergence. Taxa diverge, and convergence is a characteristic of the evolution of organs (similar functions in non-homologous organs) and (or) life forms of distant taxa with the acquisition of external similarity.
- Convergence (from lat. convergo - approaching, converging)
- Mammals adapted to gliding jumps: 1 - woolly wing, 2 - marsupial squirrel, 3 - flying squirrel
Slide 10
- Parallelism - convergence of homologous organs
- The posture of "standing in a column" and the location of the eyes on the head, characteristic of rodents in open spaces. In the bottom row are related forms in other biotopes.
- 1 - small ground squirrel, 2 - Brandt's vole, 3 - yellow pied, 4 - large gerbil, 5 - common squirrel, 6 - eastern vole, 7 - afternoon gerbil.
- Parallelism in the development of limbs in equines and liptoterns in the Neotropics
slide 11
- The term parallelism is also used not to characterize changes in organs, but to indicate the direction of evolution of taxa.
- An example of parallel evolution can be the Quaternary history of whitefish: spreading from a single center (West Siberian sea-lake) throughout the north of the Holarctic, they formed a number of isolated groupings of the subspecies-semispecies-superspecies rank. Within the isolates, independent differentiation occurs into few stamen forms, feeding on benthos, and many stamens, feeding on plankton, as well as a parallel division according to the place of reproduction into lake and river forms.
slide 12
- Polyphyly is the union of groups of different origin into one taxon. Poly is a lot, phylum is a branch.
- In the second half of the 20th century, many researchers tried to prove the polyphyletic origin of such well-known groups as flowering, amphibians, and mammals.
- Monophyly is the origin of a taxon from a single ancestral taxon.
- Simpson proposed to consider as monophyletic taxa that are generated by a taxon equal in rank to them (monophyly according to Simpson).
- However, the rank of higher taxa is subjective.
- Ashlock suggested that supraspecific taxa be considered monophyletic, descended from one ancestral species (Ashlock monophyly)
- A rather representative school of cladists accepts a more strict criterion of monophyleticity - origin from one species, but how to prove it and how to operate with it? It is pointless to use Ashlock monophyly, which is deprived of the possibility of verification.
slide 13
- Neutralist theory of evolution - neutral signs only diverge. Paraphilia and polyphilia are excluded at this level.
- Innovative news: evolution is two-headed, like an eagle on a ruble.
- Head number 1. Adaptive evolution, Darwinian evolution - the evolution of adaptations guided by selection. It can be convergent, divergent, progressive-regressive, etc.
- Head number 2. Neutralist evolution, non-Darwinian evolution - the evolution of traits that are indifferent to selection (the difference in the thickness of the lips between blacks and Indians). If a trait is not subject to stabilizing or driving selection, it always "spreads out".
- Analogy - the divergence of languages in the cultural isolation of their speakers. The divergence of languages is the greater, the longer the isolation: man - man, men - Mensch. They are not tied to either the terrain or the climate.
Slide 14
Neutral evolution is the key to phylogeny
- Phylogenetic relationships between 8 groups of vertebrates (upper diagram) and differences in the number of amino acid substitutions (Kaa) in the same species (lower graph) for hemoglobin α-chains (black dots) and β-chains (light dots). From Kimura, 1985)
- Additive tree based on differences in transfer RNAs.
- It cannot be done otherwise.
- The phylogeny of such large groups is created only by analyzing the evolution of macromolecules.
slide 15
Macroevolution - modern complexities
- To date, the possibilities of morphological, embryological, and paleontological methods for analyzing phylogeny have been practically exhausted. With their help, it was possible to create a relatively complete picture of the evolution of vertebrates and vascular plants, and partially of invertebrates.
- Lower plants and prokaryotes do not lend themselves to traditional analysis.
- Since the 1980s, there has been rapid progress. IN in general terms the contours of phylogenetic relationships of all living things are outlined. The overall design was completely unexpected.
- The new knowledge is based on a new method - the study of the evolution of molecules, first - neutral, then, already in this century, adaptive.
- At the initial stage of evolution, active "horizontal" gene transfer is observed - their exchange between representatives of very distant systematic groups. This is the main factor in the evolution of the Archean and, to a lesser extent, Proterozoic biota.
- In eukaryotes, it is accompanied by cell fusion or the absorption of a cell by a cell with the most varying degrees autonomy of individual components of a common superorganism (symbiogenetic theory).
- The phylogenetic scheme at this level is not a tree, but a network.
slide 16
- The evolutionary tree of eukaryotes. Branch points from the main stem above the Euglenozoic are arbitrarily marked.
Slide 17
Horizontal gene transfer - what it leads to
- Prokaryotes are represented by two kingdoms - archaebacteria and eubacteria
- Domain - a conservative sequence of amino acids present in several (usually many) protein molecules in different organisms. Most domains are characterized by a strictly defined function and are functional blocks of protein molecules.
- In the eukaryotic genome, proteins responsible for operations with the genome (replication, transcription, translation) and proteins that perform operations with membranes are from archaea, proteins, proteins of basic metabolism are from eubacteria.
- there is a hypothesis that the primary prokaryotic non-nuclear organism was formed by the fusion of archaebacteria with eubacteria, and the basic energy metabolism of this organism was of a eubacterial nature (glycolysis, fermentation)
- Quantitative ratio of common and unique protein domains in archaea, bacteria and eukaryotes. The areas of the figures are approximately proportional to the number of domains (from A.V. Markov, A.M. Kulikov, 2004).
Slide 18
Biological progress: the tension between complexity and success
A.N. Severtsov removes it, separating biological and morpho-physiological progress
Biological progress:
- increase in the number of individuals
- progressive settlement and the capture of new areas
- breakdown of a taxon into subordinate systematic units
Morpho-physiological progress:
- differentiation of the organism
- function intensification
- Severtsov's followers add an improvement in integration, rationalization of the body structure, an increase in the level of homeostasis, etc.
Morpho-physiological progress is one of the ways to achieve biological progress.
As well as morpho-physiological regression.
Slide 19
The main philosophical problem of macroevolution is the orientation
- Early evolutionists explained the development of nature in terms of final causes, the desire for progress, creative power, and similar agents.
- Darwin removed the predetermination of the course of evolution, but not everyone liked it.
- Periodically, both abroad and in our country, heresies arose, aimed at searching for reasons for evolution other than natural selection.
- Darwinism is a theory that allows you to explain everything “backward”, but leaves no room for predictions – how does it differ from theories of other social and social sciences. Darwinian evolution is random and unpredictable.
- In the USSR, the rejection of Darwinism went under the flag of nomogenesis - an attempt to build evolution on the basis of "laws" (nomos in Greek - law). They ended in nothing, but nomogenetics - L.S. Berg, A.A. Lyubishchev - were such bright and original personalities that nomogenesis became an important page in the history of Russian biology.
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Our first task is to form the concept of "macroevolution" and compare it with the concept of "microevolution" (Slides 3, 4)The difference between macroevolution and microevolution:
Macroevolution - supraspecific evolution, leads to the formation of taxa of a higher rank than the species (genera, families, orders, classes, types, etc.)
Microevolution occurs within a species, within its population.
Macroevolution occurs in historically grandiose periods of time and is not accessible to direct study.
Similarities of macro- and microevolution:
- The processes are based on: hereditary variability, the struggle for existence, natural selection, isolation.
- They are divergent.
Science has a lot of evidence that testifies to the reality of macroevolutionary processes.
Groups of evidence for the evolutionary process: paleontological , embryological, comparative anatomical (morphological), molecular biological and cytological, biogeographic (Slide 5)
Working on terms. (Slides 6, 7)
What do sciences study?
Paleontology, embryology, comparative anatomy, molecular biology, biogeography
What do the terms mean?
Ontogeny, phylogeny, divergence, convergence, homologous organs, similar organs, rudiments, atavisms, endemics, relics
The teacher gives assignments to the groups.(Presentation, Slide 8)
Tasks.
1. Using the textbook A.A. Kamensky, E.A. Kriksunov, V.V. Pasechnik "General biology" 10-11 cells § 61, (optional) textbook D.K. Belyaeva "General biology" 10-11 cells § 41 and materials lying on the tables find facts that prove the existence evolutionary process on our planet.
Group I - paleontological evidence of evolution;
Group II - embryological evidence of evolution
Group III - comparative anatomical evidence of evolution;
Group IV - molecular biological and cytological evidence of evolution;
Group V - biogeographic evidence of evolution.
2. The leader of each group presents the group's work to the class.
3. The work of the group is evaluated in points(groups receive tokens):
The teacher makes an installation to fill in the table.
(Slide 9)
After each group performance teacher demonstrates evidence of evolution using the Cyril and Methodius Virtual School and the Presentation and summarizes the group's work.
Paleontological evidence for evolution:
(EMC "Virtual School of Cyril and Methodius" Slide 2-5, lesson 7, Slides 22-24);
- the presence of fossil remains;
- the presence of transitional forms;
– presence of phylogenetic series (horses)
Embryological evidence for evolution:
(EMC "Virtual School of Cyril and Methodius" Slides 6-8, lesson 7);
- the law of germline similarity;
- biogenetic law.
Comparative anatomical (morphological) evidence of evolution:(Slides 12-19)
- the cellular structure of organisms;
- the general plan of the structure of vertebrates;
- the presence of homologous and similar organs;
- the presence of rudiments and atavisms;
- the presence of living intermediate forms
Molecular biological and cytological evidence for evolution:(Slides 20-21)
– elementary chemical composition;
– structure and functions of organic molecules;
- energy accumulator - ATP molecules;
– genetic code (universal);
- protein biosynthesis;
- the structure and function of cell organelles;
cell division (mitosis and meiosis).
Biogeographic evidence for evolution.(Slides 25-32)
A. Wallace singled out 6 zoogeographical areas on the distribution of animals and plants on our planet.
Questions:
1. Why do the flora and fauna of the Nearctic region (North America) and the Paleoarctic region (Eurasia) have much in common, although they are isolated by the Bering Strait?
2. Why is the flora and fauna of the Nearctic region (North America) different from the Neotropical region (South America), although they are connected by the Isthmus of Panama?
3. Why the flora and fauna of the Neotropical region (South America) and the Ethiopian region (Africa) have much in common ?
4. Why are marsupials only in Australia?
5. Why is the flora and fauna close to the mainland in the British Isles, and why are there no large ungulates, large predators, and higher apes typical of Africa on the island of Madagascar?
However, there are many lower monkeys - lemurs, which are not found anywhere else (endemic).
Teacher: The peculiarity of the fauna and flora of the islands testifies in favor of evolution.
Question: Why are oceanic islands so poor compared to mainland islands?
They are the result of accidental introduction of certain species of birds, reptiles, insects, plant seeds, spores, which were able to overcome water barriers and be brought in by wind, water, birds. Representatives of such species that have fallen on oceanic islands receive ample opportunities for reproduction.
For example, in the Galapagos Islands, out of 108 bird species, 82 and 8 reptile species are endemic.
The Hawaiian Islands have 300 endemic species of snails belonging to the same genus.
The distribution of animals and plants on the surface of the planet and their grouping into biogeographic zones reflects the process of the historical development of the Earth and the evolution of the organic world.
Output:(Slide 33)
To prove the authenticity of the evolution of the living world on Earth, it is necessary to use data from different sciences.
Micro- and macroevolution. Signs. Microevolution. Macroevolution. The result of evolutionary transformations. Formation of new species. Formation of supraspecific taxa-genera, families, orders, etc. Mechanisms. The action of undirected factors of microevolution (mutational and combinative variability, population waves, gene drift, isolation), the guiding factor is natural selection. It does not have specific mechanisms and is carried out only through microevolutionary processes. duration. Occurs within a species at the population level. It can occur in a historically short time and be accessible to direct observation. It goes on a superficial level. Requires historically long periods of time and is not accessible to direct observation.
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"Evidence for Evolution" - Elephant Tortoise. Ichthyostega. Genetic evidence Universality of the genetic code. 1. The law of germinal similarity. Basic evidence for evolution. Archeopteryx is a transitional form from reptiles to birds of the Jurassic period. 2. Information about fossil transitional forms of organisms. 2. The principle of recapitulation is a biogenetic law.
"Evolution of the organic world" - Hoatzin - a modern bird, in some ways similar to Archeopteryx. Prutvirai Patil, 11, is from the village of Sanglivadi in the Indian state of Maharashtra. Embryological Paleontological Biogeographic Comparative anatomical. Wing? Charles Bonnet. Platypus. Human coccyx. Caudal appendage.
"Evolution and its evidence" - Evolution is gradual and long-term. Embryological data. Holarctic region: Paleoarctic (Eurasia) and Neoarctic (North America). Factors in the creation of varieties and breeds are hereditary variability and artificial selection. Hence the definition of a species as a genetically integral and closed system.
"Evidence of the evolution of the organic world" - Why are marsupials only in Australia? What material was understood completely or partially? Embryological. Settlement of the islands. A. Wallace identified 6 zoogeographic areas for the distribution of animals and plants on our planet. The general plan of the structure of vertebrates. Why are oceanic islands so poor compared to mainland islands?
"Macroevolution" - Darwinian evolution is random and unpredictable. Divergence within the mustelid family. Aramorphosis, parallelism, etc. are not a cause, but a statement. The overall design was completely unexpected. Aramorphosis according to A.N. Severtsov does not have a clear definition. Convergence is not the exact opposite of divergence.