Ethological Aspects of Stress in a Model Lizard, Anolis carolinensis

Research on the stress response in reptiles can provide a useful comparative perspective for understanding how the constituent elements of the response can be put into service of diverse behavioral adaptations. A summary of the neural and endocrine causes and consequences of specific behavioral patterns seen in the small diurnal lizard, Anolis carolinensis, has provided a model for the exploration of the dynamics of autonomic and neurohormonal contributions to adaptive behavior. In this species, changes in body color provide indices of the flux of circulating stress-relevant hormones, and are seen in situations from spontaneous exploration through agonistic behavior. Furthermore, captive adult males spontaneously and consistently manifest social dominance relationships that provide many of the elements of a stress-mediated adaptive behavioral patterns. These patterns include suppressed reproduction and long-term coping apparently based more on stress-mediated changes in motivation than acquired changes in behavior.