The effect of large body size on the temperature regulation of the komodo dragon, Varanus komodoensis

Abstract

1. 1. Field measurements of the body temperature of the Komodo monitor, Varanus komodoensis, were normally between 36 and 40°C during the day, a range that is midway between shaded air temperatures and radiant temperatures in the sun. 2. 2. At night, the temperature differential of reptiles depends upon body weight. 3. 3. Large lizards often have appreciable temperature differentials because of their thermal inertia, relatively low thermal conductances, and inability to come to a thermal equilibrium over night. 4. 4. Larger reptiles, such as the Galapagos tortoise, have still larger differentials, because they have very low conductances produced by an integument that acts like a thermal barrier. 5. 5. These relationships lead to the conclusion that dinosaurs probably were inertial homoiotherms.