Homosexual Behavior and Dominance Hierarchy in a Group of Captive Female Squirrel Monkeys (Saimiri sciureus)

Abstract

Rank order hierarchy was evaluated in four adult female squirrel monkeys in a variety of situations. Dominance relationships were first determined for pairs of monkeys before and after deafening the subordinate monkey. Three of the four monkeys were deafened in this manner. Deafening had no apparent permanent effect on social behavior. The four monkeys were then observed as a group in a large cage, isolated from all other monkeys. The frequency distributions of food stealing, body grasping, and sexual behaviors were consistent with a linear rank order interpretation. For some behavioral units dyadic relationships between monkeys were found to be more reliable predicators of linear hierarchy than frequency distribution. Homosexual encounters appeared to resemble the heterosexual pattern. Linear hierarchy has been observed by others in adult male squirrel monkey groups but not among subadult females.