Field Thermoregulatory Behavior in the African Spiny-Tailed Lizard Uromastyx acanthinura.

Season and altitude, together with intrinsic factors such as sex and body size, can induce changes in the field body temperatures of lizards. Accordingly, the purpose of this paper was to understand the thermal biology of Uromastyx acanthinura based on behavioral observations in the field. We investigated the influence of altitude, seasonal variation, and intrinsic characteristics on thermoregulation in U. acanthinura by monitoring adult individuals in the field during their active season in southern Tunisia. Our study shows that larger individuals achieve their active body temperature by spending more time exposed to full sun (basking). Seasonal and sex-based variations in thermoregulatory behaviors are also shown. These variations could be due to environmental conditions and/or a response to reduced food availability, or the result of seasonal hormonal cycles. Thermoregulatory behaviors did not significantly differ with changes in altitude. Moreover, our results suggest that these animals would respond to microclimatic changes by modifying their postures to attain the activity temperature. Further investigation is required involving both field and laboratory approaches in order to evaluate future species responses more accurately under global warming. [ABSTRACT FROM AUTHOR]