Food consumption does not affect the preferred body temperature of Yarrow's spiny lizard (Sceloporus jarrovi)

When animals consume less food, they must reduce their body temperature to maximize growth. However, high temperatures enhance locomotion and other performances that determine survival and reproduction. Therefore, thermoregulatory behaviors during different metabolic states reveal the relative importance of conserving energy and sustaining performance. Using artificial thermal gradients, we measured preferred body temperatures of male spiny lizards (Sceloporus jarrovi) in fed and fasted states. Both the mean and maximal body temperatures (33 degrees and 35 degrees C, respectively) were unaffected by metabolic state. This finding suggests that the benefits of foraging effectively, evading predators, and defending territory outweigh the energetic cost of a high body temperature during fasting. (C) 2010 Elsevier Ltd. All rights reserved.