Acclimatization versus Acclimation of Activity Metabolism in a Lizard

Abstract

We collected green anoles, Anolis carolinensis, from a northern population of this species at four times during the year and then measured their oxygen consumption and lactate concentration at rest and during induced exercise at 20 C. The data were then compared with data previously collected from specimens acclimated to cold and warm conditions in the laboratory. The seasonal changes in resting and exercise oxygen consumption and in resting and postactivity lactate concentration were not parallel. Acclimatization of animals to natural climatic alterations over the course of the year did not always result in the same changes seen in specimens acclimated in the laboratory to cold and warm conditions. Aerobic support for exercise in this nonhibernating species does not vary from season to season. However, the capacity of these lizards to power locomotion by glycolysis is strongly depressed after several months of winter. This seasonal change in the anaerobic capacity of these lizards may be associated with their reluctance to venture far from their crevices in winter even on warm, sunny days when their aerobic capacity would be high.