The ratio of macroevolution and microevolution presentation. Presentation on the topic "Microevolution. Speciation". The main philosophical problem of macroevolution is orientation

Slide 3

Macroevolution - plot marking

• The study of paleontological finds and modern forms makes it possible at present to consider the existence of two main types of evolutionary development of the group as quite firmly established (Lamark, 1809, Haeckel, 1866; and others): the emergence of a large number of closely related forms differing in adaptations of the same scale, and development with the release to another adaptive zone due to the acquisition by the group of some fundamentally different adaptations that allow them to go beyond the boundaries of the former adaptive zone.
• 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 stop at one of these terms; one of the most appropriate seems to be the term "allogenesis" (Paramonov, 1966). The terms "aromorphosis" and "anagenesis" were used to describe the development of a group on the way to a different adaptive zone, the acquisition of evolutionary adaptations. ... we, following AL Takhtadzhyan (1966), use the term “arogenesis” for such group transformations.
• (From Timofeev-Resovsky, etc.)
• Aramorphosis according to A.N. Severtsov has no clear definition. Usually it is set graphically

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• Evolutionary transformations that significantly increase the adaptive capacity of this group (allowing 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 general level of organization, were called epectomorphoses. ... Eppectomorphoses persist for a long time in the course of subsequent adaptive radiation, becoming traits of large taxa
• Schmalhausen suggested calling the 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 private adaptations - allogenesis or cladoggenesis
• Diagram of the main directions of the evolutionary process:
• A - arogenesis, AL - allogenesis, K - catagenesis, E - epectogenesis
• Planes represent different levels of organization
• From the Jordanian

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• 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.
• So, the undoubted aromorphoses in the evolution of vertebrates were: the development of the mechanism of active ventilation of the gills (gill pump) in ancient vertebrates through movements of the visceral gill skeleton, the acquisition of the jaw apparatus (with the rearrangement of the anterior gill arches), intensification of ventilation of the gills with the development of the gill cover in the bony 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 - amniotic embryonic membranes (amnion, serosa, allantois), which provide the possibility of laying eggs on land; development of a powerful suction (dilution) breathing pump of the chest in reptiles; the formation of an aircraft in birds; development of viviparity 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 - posterior-frosted, narrow-shaped, 4,5,9 - asp, 6, 10 - viper
• Rhinoceros skull
• Snake Skull Modifications - An Example of Epectogenesis
• Free, movable, rotating upper jaw and free, sliding lower jaw - epectomorphosis, which allowed snakes
• move from feeding on insects (the food spectrum of legless lizards) to hunting vertebrates. The general level of vital activity (energy exchange) remains the same.
• Video

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• Divergence (from medieval Latin divergo - deviate)
• The wolverine feeds mainly on carrion. Wide paws with membranes between the toes help her to move through loose snow in the northern taiga and forest-tundra. Weight about 15 kg.
• Weasel is the smallest of the mustelids. It 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 the range in winter. Builds very complex burrows, in which he spends most of his time. Weight about 15 kg.
• Divergence within the marten family

Slide 9

• Convergence is not the complete opposite of divergence. Taxa diverge, and convergence is a characteristic of organ evolution (similar functions in non-homologous organs) and (or) life forms 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 position of the eyes on the head, characteristic of rodents of open spaces. The bottom row contains related forms in other biotopes.
• 1 - lesser ground squirrel, 2 - Brandt's vole, 3 - yellow pied, 4 - great gerbil, 5 - common squirrel, 6 - eastern vole, 7 - tinned gerbil.
• Parallelism in the development of equine limbs and liptoterns in the Neotropics

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• 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 whitefishes: spreading from a single center (West Siberian Sea-Lake) throughout the north of the Holarctic, they formed a number of isolated groupings of subspecies-semi-species-superspecies rank. Inside the isolates, there is an independent differentiation into small-scaled forms feeding on benthos and multi-scaled forms feeding on plankton, as well as a parallel division at the breeding site into lacustrine and river forms.

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• Polyphilia is a union of groups of different origins into one taxon. Poly - a lot, phylum - a branch.
• In the second half of the twentieth century, many researchers tried to prove the polyphyletic origin of such well-known groups as flowering, amphibians, mammals.
• Monophilia is the origin of a taxon from one ancestral taxon.
• Simpson proposed to consider monophyletic taxa that are generated by a taxon equal to them in rank (Simpson monophilia).
• However, the rank of higher taxa is subjective.
• Ashlocke proposed to consider supraspecific taxa derived from one ancestral species (monophyletic according to Ashlocke) as monophyletic
• A fairly representative school of cladists accepts a stricter criterion of monophyleticity - origin from one species, how to prove it and how to operate with it? It is pointless to use Ashlock's monophilia, which is deprived of the possibility of checking.

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• Neutralist theory of evolution - neutral signs only diverge. Paraphilia and polyphilia are excluded at this level.
• Innovative news: the evolution of the two-headed, like an eagle on a ruble.
• Head # 1. Adaptive evolution, Darwinian evolution — the evolution of selection-directed adaptations. It can be convergent, divergent, progressive-regressive, etc.
• Head # 2. Neutralist evolution, non-Darwinian evolution — evolution of traits that are indifferent to selection (the difference in the thickness of the lips between Negroes and Indians). If a trait is not subject to stabilizing or driving selection, it always “diffuses”.
• An analogy is the divergence of languages ​​with the cultural isolation of their speakers. The longer the isolation, the greater the divergence of languages: man - cholovik, men - Mensch. They cannot be tied either to the terrain or to the climate.

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Neutral evolution is the key to phylogeny

• Phylogenetic relationships between 8 groups of vertebrates (top diagram) and differences in the number of amino acid substitutions (Kaa) in the same species (bottom graph) in the α-chains of hemoglobin (black dots) and β-chains (light dots). From Kimura, 1985)
• An additive tree built on the basis of differences in transport RNAs.
• It cannot be done otherwise.
• The phylogeny of such large groups is created only by analyzing the evolution of macromolecules.

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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 picture of the evolution of vertebrates and vascular plants relatively completely, invertebrates - partially.
• Lower plants and prokaryotes defy traditional analysis.
• Since the 1980s, there has been rapid progress. In general terms, the contours of the phylogenetic relationships of all living things are outlined. The overall design turned out to be completely unexpected.
• The new knowledge is based on a new method - the study of the evolution of molecules, first - neutral, then, already in the present century, adaptive.
• At the initial stage of evolution, there is an active "horizontal" transfer of genes - 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 biotas.
• In eukaryotes, it is accompanied by cell fusion or absorption of a cell by a cell with a very different degree of autonomy of individual components of the general superorganism (symbiogenetic theory).
• The phylogenetic scheme at this level is not a tree, but a network.

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• Evolutionary tree of eukaryotes. Branching points from the main trunk above the Euglenozoa are marked arbitrarily.

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Horizontal gene transfer - what does it lead to

• Prokaryotes are represented by two kingdoms - archaebacteria and eubacteria
• Domain is a conservative sequence of amino acids present in several (usually many) protein molecules in different organisms. Most of the 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 carry out operations with membranes - from archaea, proteins, basal metabolic proteins - from eubacteria.
• there is a hypothesis that the primary prokaryotic nuclear-free organism was formed by the fusion of archaebacteria with eubacteria, and the basic energy metabolism of this organism was of eubacterial nature (glycolysis, fermentation)
• The 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).

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Biological Progress: The Contradiction Between Complexity and Success

A.N. Severtsov removes it, dividing biological and morpho-physiological progress

Biological progress:

• increase in the number of individuals
• progressive resettlement and seizure of new areas
• decomposition of a taxon into subordinate systematic units

Morpho-physiological progress:

• differentiation of the organism
• intensification of functions
• 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 orientation

• The early evolutionists attributed the development of nature through finite causes, the drive for progress, creative power, and the like.
• Darwin removed the predetermined course of evolution, but not everyone liked it.
• Periodically, both abroad and in our country, heresies arose, aimed at finding other causes of evolution, besides natural selection.
• Darwinism is a theory that allows you to explain everything "backward", but leaves no room for predictions - how it differs from the 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 - attempts to build evolution on the basis of "laws" (Greek nomos - 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.