Physiological model of the stabilizing form of natural selection at the cellular level

By means of directional elimination of the parental gametes in frogs, the effects of two basic forms (i.e. normalizing and canalizing ones) of natural selection on the heat resistance level of muscle fibers in the progeny have been reproduced. Experimental evidence is presented that both male and female gametes account for hereditary transformation of cellular heat resistance as a quantitative physiological parameter. Polymodal pattern of regulation of this parameter is suggested which includes indispensable participation of both thermal and non-thermal factors of selection. The environmental temperature, as a selective factor, accounts for the formation of cellular heat resistance directly, whereas non-thermal factors exert their control on this parameter indirectly, associatively. It is suggested that the polymodal pattern of regulation of physiological functions presents the main mode of realization of canalizing form of natural selection.