Dominance status predicts response to nonsocial forced movement stress in the green anole lizard (Anolis carolinensis).
We used changes in body color and eyespot formation, two somatic indices of stress controlled mainly by catecholamine activity, to compare the reactions of dominant and subordinate male green anole lizards (Anolis carolinensis) to a nonsocial stressor, forced movement. Individual males were pretested by subjecting them to 10 min of forced movement induced by chasing them around their home cage with a slender wooden stick. Stress responses were assayed via changes in body color (progressive darkening from green to brown indicating increasing stress) and expression of a black postorbital eyespot (which appears with increasing catecholaminergic stress responses). Lizards were paired and allowed to form stable dominant/subordinate relationships for 2 weeks. After that period of stable social status, dominants and subordinates were separated and subjected to the same forced-movement stress. There was no difference between experimental groups in the pretest. After assuming positions in the dominance hierarchy, however, dominant males showed reduced somatic indicators of stress and were quicker to recover from the stress. The data suggest that animals that assumed the dominant position decreased their stress response relative to the pretest, while animals that assumed the subordinate position increased their stress response relative to the pretest. The results indicate that dominant social status may have advantages beyond the realm of social interactions by enhancing an individual's ability to tolerate other, nonsocial stressful events.
Plavicki
Jessica
J
Department of Psychology and Institute for Neuroscience, University of Texas, 1 University Station A8000, Austin, TX 78712-0187, USA.
Yang
Eun-Jin
EJ
Wilczynski
Walter
W
D000223:Adaptation, Psychological / Q000502:physiology; D000818:Animals; D003345:Corticosterone / Q000097:blood; D004291:Dominance-Subordination; D008116:Lizards / Q000502:physiology*; D008297:Male; D009043:Motor Activity / Q000502:physiology; D012880:Skin Pigmentation / Q000502:physiology*; D013315:Stress, Psychological / Q000097:blood*; D013739:Testosterone / Q000097:blood
D013739:Testosterone; D003345:Corticosterone