adaptation defined in 1939 year

adaptation - Adaptation (Lat. ad, to; aptare, to fit);
adaptation - Biological process by which any living organism adjusts itself or is modified to suit the conditions of its existence. In order to survive it must achieve a more or less close adaptation to its surroundings; an obvious example is the dragon-fly whose larva is fitted for life in water while in the insect form its structure is adapted for life on land. Adaptations may be inherent in the germ cell, having probably been fixed by natural selection and transmitted by heredity. In animal evolution certain characteristics may tend to be developed or modified. If they are favourable to the survival of the species, such variations or mutations constitute a process of adaptation. See Evolution.

adaptation defined in 1951 year

adaptation - adaptation;
adaptation - (1) Evolutionary. Any characteristic of living organisms which, in the environment they inhabit, improves their chances of survival and ultimately of leaving descendants, in comparison with the chances of similar organisms without the characteristic; natural selection therefore tends to establish adaptations in a population. An adaptation to a particular feature of the environment means a characteristic which is an adaptation because it reduces destruction by that particular feature. An adaptation to a particular activity of an organism (e.g. to flying) means simply a characteristic which makes possible or improves performance of that activity without necessarily being measured in terms of survival, though usually that is implied. (2) Physiological. Change in an organism as a result of exposure to certain environmental conditions which makes it react more effectively to these conditions. (3) Sensory. Change in excitability of a sense-organ as a result of continuous stimulation such that a more intense stimulus becomes necessary to produce the same response. E.g. contact of an object with the skin at once excites the touch receptors; but if contact is simply maintained the touch receptors quickly cease to respond, though they will respond again to a more intense stimulus. Different receptors differ much in the extent of their adaptation.

near adaptation in Knolik

letter "A"
start from "AD"
adaptive enzyme

definition of word "adaptation" was readed 688 times

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