• Artikel

Adaptive responses in animals to climate change

Af L. Scott Mills (2016)
Global climate change can act as a stressor on wild animal populations in several ways. Direct effects can occur when a change in climate exceeds physiological optima for species, such as when waterfowl or amphibians confront dry breeding ponds, or polar bears face reduced sea ice. In other cases, the effects of climate change create mismatches with seasonal phenological processes (note that phenology refers to the timing of seasonal activities of animals and plants throughout the year). Examples of phenological events in animals include migration, hibernation, mating, and change of coat color to match winter snow (Fig. 1). Phenological processes in animals are often initiated by day length (or photoperiod) because it is a historically excellent predictor of seasonal environmental conditions (decreasing day length heralds the coming of autumn, whereas increasing day length tracks spring). However, if these seasonal environmental conditions are altered by climate change (for example, earlier times of snow melting or increases in spring temperatures), then a day length–controlled phenological trait in an animal may become mismatched with its optimal conditions.