Adaptive variation in the upper limits of avian body temperature.

ABSTRACT: Physiological performance declines precipitously at high body temperature (T_b), but little attention has been paid to adaptive variation in upper T_b limits among endotherms. We hypothesized that avian maximum tolerable T_b (T_bmax) has evolved in response to climate, with higher T_bmax in species exposed to high environmental heat loads or humidity-related constraints on evaporative heat dissipation. To test this hypothesis, we compared T_bmax and related variables among 53 bird species at multiple sites in South Africa with differing maximum air temperature (T_air) and humidity using a phylogenetically informed comparative framework. Birds in humid,

SUBMITTER: Freeman MT 

PROVIDER: S-EPMC9245658 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature