Thermal ecology of the high-altitude bunch grass lizard, Sceloporus scalaris
The thermal ecology of a high-altitude lizard, Sceloporus scalaris, was investigated in the Chiricahua Mountains of southeastern Arizona, where the lizards are active on sunny days throughout the year. Mean body temperature was 32.6 °C (range 12.6–39 °C) and mean air temperature was 20.2 °C (range 5.2–36.4 °C). The slope of the body temperature versus air temperature regression was 0.23. Monthly differences in body temperature were observed, with the highest body temperatures observed in early summer. Lizards at three study sites with differing slope and vegetative cover had different mean body temperatures. Males had higher body temperatures than both nongravid and gravid females. Maintenance of elevated body temperatures even during winter lengthens the activity and growing season, permitting early maturity with potentially important life-history consequences.