BORRELL, B.J.*; LADUC, T.J.; DUDLEY, R.: Physiological cost of head-body temperature differences in snakes

Head-body temperature differentials observed in reptiles and other ectotherms may be important for central nervous system functioning, but the maintenance cost of this differential in terms of water loss has never been studied. Using infrared themography, we measured head-body temperature differentials in three snake families: viperids, colubrids, and boids. Some snake taxa maintain a temperature differential greater than 3 degrees C via respiratory cooling. We estimate the physiological cost associated with such water loss andcompare these costs among clades and habitats. We also discuss the benefits of respiratory cooling in terms of the thermoreceptive capabilities of boids and viperids.