Meeting Abstract
Many species of lizards heat more quickly than they cool. This is important because it allows them to stay at preferred body temperatures for longer periods during the day, and therefore allows lizards longer periods to perform various activities, like foraging. This phenomenon has been well studied in iguanid lizards, and the difference is particularly big in large-bodied lizards. We tested to see if the piebald chuckwalla, Sauromalus various, a large bodied iguanid, had control over the rate of change in body temperature by measuring the amount of time needed to heat or cool by 10 C, between 25 C and 35 C. We found that these desert iguanids had a ratio of heating to cooling rate of 0.654±0.063 and heated from 25 to 35 C in 6.2±0.9 minutes, while cooling from 35 to 25 C in 9.1±1.6 minutes. The ratio of these rates is similar to other desert iguanids, including the smaller, common chuckwalla, S. ater. Thus it appears that these desert iguanids have some physiological control over body temperature changes, that allows them to stay at a preferred temperature as long as possible.
