poikilothermic, a. Physiol.
(ˌpɔɪkɪləʊˈθɜːmɪk)
[ad. G. pökilotherm (now poik-) (C. Bergmann 1847, in Göttinger Studien I. 613): see poikilo- and thermic a.]
Characterized by a body temperature that varies with the temperature of the environment; cold-blooded. Also ˌpoikiloˈthermal, -ˈthermous adjs., in the same sense. Opp. homœothermic a.
| 1884 tr. Claus' Zool. I. 74 Most of the lower animals are poikilothermic, or, as they have less appropriately been called, cold-blooded. 1885 W. Stirling tr. Landois's Text-bk. Human Physiol. I. vi. 426 The so-called cold-blooded animals are called poikilothermal. 1928 Pearse & Hall Homoiothermism i. 2 The change from the poikilothermic to the homoiothermic condition. Ibid. iv. 27 The extreme minimum temperature which poikilothermal animals can tolerate. 1933 R. H. Wolcott Animal Biol. lxiv. 456 Animals which can maintain a constant temperature are termed homoiothermous..; animals unable to do so are termed poikilothermous, or cold-blooded. 1956 Sci. News XL. 71 Under ordinary circumstances most poikilothermous animals have body temperatures that fall when the environment becomes cooler, and rises when it becomes warmer. 1963 Lancet 5 Jan. 29/1 Newborn infants are poikilothermic, and their temperatures may be rapidly reduced. 1973 Marine Biol. XXI. 262/2 Lower poikilothermal animals (protozoans, sponges, some coelenterates). 1973 P. A. Colinvaux Introd. Ecol. xx. 288 Poikilothermous lizards are not excluded from the Arctic because they are poikilothermous, but because, on the average, they cannot balance their heat budgets if the ambient temperature is low. |
Hence ˈpoikilotherm, a poikilothermic animal.
| 1934 in Webster. 1950 C. L. Prosser in C. L. Prosser et al. Compar. Animal Physiol. x. 349 Aquatic poikilotherms follow changes in environmental temperature rapidly and precisely. 1965 B. E. Freeman tr. Vandel's Biospeleol. xix. 326 Resistance to starvation is a general property of poikilotherms. 1968 [see homœotherm]. |