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  • Title: [Some problems of the evolutionary adaptatiogenesis].
    Author: Iordanskiĭ NN.
    Journal: Zh Obshch Biol; 2009; 70(5):372-82. PubMed ID: 19891410.
    Abstract:
    Evolution of organisms is adaptive process as a whole, but its adaptiveness is fully revealed in long periods of phylogenesis. To form the complex adaptations, the phyletic evolution is more favourable than relatively short-term processes of speciation. Selection can influence on a given character of organism only after achievement of some minimal selectable degree of its development, that is specific for each adaptation. For some complex adaptations, the minimal selectable value of the character can be essentially higher than the initial degree of its expression. In such cases the corresponding adaptations evolve either on the basis of the morpho-functional preadaptations or using some relatively large hereditary changes ("saltations") as the elementary evolutionary material for selection. The negative consequences of such saltations can be mitigated by the compensatory ontogenetic modifications. Elucidation of the minimal selectable value of characters seems to be useful also to evaluate probability of the hypotheses explaining adaptive causes of corresponding evolutionary transformations. The notions of the ecto- and endosomatic organs (after A.N. Severtzov, 1939) are relative ones. The primary evolutionary changes (protallaxes) can arise in any organism system and cause the arising of secondary alterations (deutallaxes, or internal adaptations) in other system.
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