Should I stay or should I go? The influence of temperature and sex on predator-induced responses in newts

Ectotherms compensate for variation in thermal environments in diverse behavioural ways. Despite widely occurring sex differences in morphology and physiology, the sex-specific thermal sensitivity of behavioural traits has received little attention. We tested the interactive influence of sex and environmental temperature on predator-induced responses in the Alpine newt, Ichthyosaura alpestris. Escape decisions and the duration of flight were less thermally sensitive in females than in males. Males ran more slowly than females. Both sexes required more stimuli at intermediate temperatures than at other temperatures. We conclude that temperature and sex are important determinants of a newtʹs defensive repertoire. The sex-specific thermal sensitivity of defensive responses suggests both asymmetric selection regimes and an impact of environmental change in newt populations.