The subordination stress paradigm and the relation between testosterone and corticosterone in male ring-necked pheasants

Abstract

The relations linking glucocorticoids, testosterone, social and sexual behaviour in vertebrates are complex and poorly understood. The conventional view is that: (1) subordinate individuals should have higher glucocorticoid concentrations (the subordination stress paradigm); (2) dominant and more active males during the breeding season should have higher testosterone concentrations; and (3) the relation between glucocorticoid and testosterone concentrations should be negative. I investigated the relation between hormones and behaviour in male ring-necked pheasants, Phasianus colchicus. Dominant and high-displaying males over the whole mating period had a higher level of both testosterone and corticosterone. As a consequence, testosterone and glucocorticoid levels were positively correlated. These results do not support the subordination stress paradigm, but they may support the stress-mediated version of the immunocompetence handicap hypothesis.