Summary: Mateos (2005)

The relationship between testosterone, glucocorticoids, social and sexual behaviour is complicated and poorly understood in vertebrates. It is thought that subordinates should have higher glucocorticoid levels (known as the subordination stress paradigm) and that dominant, more active, males should have higher concentrations of testosterone during the breeding season. It has thus been suggested that glucocorticoid and testosterone concentration should be inversely related. Mateos (2005) investigated the relationship between behaviour and hormone concentration in male ring-necked pheasants, Phasianus colchicus. She found that dominant and high-displaying males had higher levels of testosterone and corticosterone (a glucocorticoid) throughout the mating period, indicating that these two hormones are positively correlated. Mateos (2005) indicates that the results do not support the subordination stress paradigm, but she indicates that they may support the immunocompetence handicap hypothesis (through stress-mediation).