ABSTRACT
Analysis of adaptation to the thermal environment has been a major and persistent theme in physiological ecology (Prosser, 1973; Hochachka and Somero, 1984). It has also played an important role in evolutionary biology, in both experimental and theoretical studies of adaptation. Both fields have focused on temperature as a key environmental variable, because it exerts a controlling influence on nearly all the physiological rate processes, thereby affecting important biological phenomena such as growth and reproduction. Adaptation of fish to changing environmental temperatures is an important subject from both the scientific and the economic viewpoints (Berlish, 1969; De Luca et al.; 1983; Gelman et al., 1984, 1989).
