Social status constrains the stress response in the squirrel monkey.

The influence of dominance on the pituitary-adrenal and gonadal systems was evaluated in male squirrel monkeys. Basal and stress levels of plasma cortisol and testosterone were determined in eight male pairs across a 5-week period. The data indicated that squirrel monkeys have unusually high levels of steroid hormones in comparison to other species. Dominant males had higher levels of cortisol and testosterone and showed a smaller stress response than did subordinate males.