Body surface temperature and length in relation to the thermal biology of lizards

Abstract

This study investigated body surface temperature (Tbs) in 22 lizards of 18 species. The difference between Tbs and ambient temperature (Ta) was correlated with size. The greater Tbs − Ta differentials, which were recorded in larger lizards, may occur as a result of heat transfer from the core to surface in prevention of overheating. The structure of the integument may contribute to heat dissipation. Heliothermy and thigmothermy as forms of thermoregulation were also incorporated into the data set. Heliothermic lizards showed a positive correlation between length and Tbs − Ta. Thigmothermic lizards, however, exhibited a negative correlation. Differences in size and rate of conductive heat transfer are put forward as possible reasons for the negative correlation.