| 释义 |
encephalization|ɛnˌsɛfəlaɪˈzeɪʃən|
[f. Gr. ἐγκέϕαλ-ος brain + -ization.]
1. An evolutionary increase in the complexity or relative size of the brain; a shift of function from non-cortical parts of the brain to the cortex.
1938J. F. Fulton Physiol. Nerv. Syst. p. viii, Owing to greater encephalization, experimental evidence drawn from the primates is more immediately applicable to the human being than that drawn from studies of other mammals. 1940C. S. Sherrington Man on his Nature 310 What is called ‘encephalization’ is an evolutionary change which is strikingly exemplified in ourselves. It is a shifting of the function in the brain from older and more primitive to newer and more complex parts. 1972Science 19 May 804/1 A major trend in Cenozoic primate evolution has been the progressive neocortical encephalization. 1976Sci. Amer. Jan. 95/2 The step from reptiles to mammals required a certain amount of encephalization (approximately a fourfold increase in relative brain size to transform a reptilian polygon into an archaic mammalian polygon).
2. Special Comb.: encephalization quotient, the ratio of the actual size of the brain of an animal to the size that would be expected from the size in other animals, allowing for differences in body weight.
1970H. J. Jerison in Science 11 Dec. 1224/2 We may now define our measure of relative brain size as the *encephalization quotient EQi for species i, the ratio of its brain size Ei to the expected brain Ee in a living mammal of the same body size Pi. 1975Nature 24 Apr. 687/2 Using Holloway's estimates of endocranial volumes (442 cm3 for A. africanus and 530 cm3 for A. robustus), the encephalisation quotient is 4.0 for A. africanus and 4.0 for A. robustus. 1981Sci. Amer. Feb. 95/2 Overall, the encephalization quotient of the pterosaur—the ratio of the volume or weight of its brain to that of the brain of an earthbound reptile of the same size—was relatively large. |