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Isolation
Secretory system
Endurance
Otter
Otter
Vydrino
Vydrovaya the shrew
Blowing of the sowings
Breaking in
Visiting editorial staff
The out-of-town session of the law court
Viability
Overflow
Caused potentials
Calling production
Calling instrument
Abortion
Switch is electrical
Vykopochnye the forest instruments
Fillet
Vyksa
Redemption operation
Hatching
Vylcha
Vylchanov
Freezing the plants
Extinction
Extortion in
Soaking the plants
Freezing
Vfp

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Extinction

it is specific (plants, animals, microorganisms), the phenomenon, proceeding in the process of the development of living nature for the elongation of geologich. of the history of the earth. V. of organic forms occurs as a result of the natural selection with substantial changes of vnesh. of medium when organisms do not manage to be adapted to these changes or when even neznachit. of change in the condition for existences lead to the delay of the multiplication of form. Consequently, v. - important part of the evolution of living nature. The history of organic peace shows that an enormous quantity of forms died out. Zh. By Cuvier his followers attempted to explain in. catastrophes by theory. Refuting this theory, Zh B. Lamark asserted that all ischeznuvshiye forms did not die out, but they degenerated themselves into novys. Italian paleonthologist J. brokkya in the beginning. 19 v. it erroneously assumed that the forms, similar to individuals, have the specific lifetime and on reaching of known "age" die. Other hypotheses attempt to explain by v. by a change some of one factor of medium (general temperature drop either the warming up of climate, strengthening or weakening solar radiation, etc.).

Only Darwinism explains to v. in accordance with the facts of the history of organic peace. H. Darwin showed that v. of organic forms is caused by changes in the environmental conditions, moreover the great value have changes not only in the abiotic factors of environment (relating to neorganich. to peace), but also biotic factors (interspecies relations). A rapid change in the medium can be neposredstv. by reason v. specific, that occupy the limited territory or water area. However, forms and the groups of forms, which have the extensive propagation (for example, that live simultaneously in all oceans or on the majority of the continents of the terrestial globe), do not die out everywhere. Final v. of some it is specific frequently it is involved, since they can remain in the limited sections because of the local favorable conditions (usually - biotic). With this existence of the relict forms (see relicts ) is connected. V. o. Kowalevski developed and was deepened Darwinian concept v. on the basis of the facts of paleonthology, after showing that one of the most important conditions v. - inadaptivnaya evolution (see Inadaptatsiya).

In connection with the swift tech. progress and a steady increase in population one of most important biotich. of factors, which cause directly or indirectly v. mn. it is specific, becomes human activity.

Lit.: Darwin h., works, Vol. 3, M. - l., 1939; D and in t and w in both l and l. sh., the history of evolutionary paleonthology from Darwin to our days, M. - l., 1948; it. Reasons for the extinction of organisms, M., 1969: But X e of 1 g about d D I, Quaternary extinctions of large mammals. Berk. - Los Ang., 1967. L. K. gabuniya.

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