Social hierarchy under different criteria in groups of squirrel monkeys,Saimiri sciureus

Under different criteria the individual members of groups of squirrel monkeys show different social capacities. The ranking of the subjects was much the same for Restraining and Genital display. The hierarchies for Approaching and Following fitted well with each other, showing few similarities with the above two. Location of individual ranks for Withdrawing tended to be the opposite to that of Approaching and Following. Restraining and Genital display showed quasi-linear hierarchies, with males on top and females at the bottom of them. For Approaching, Following, Withdrawing, and Genital inspection the results varied from quasi-linear structure to circular or even unisexual arrangement. As a rule the animals behaved towards partners close in rank to themselves. Several individual roles could be isolated: An alpha male role, directing Restraining and Genital display to all other partners more frequently than any of them towards him, basing his ability more in adequate distribution of total performance among social partners than in high total frequency; an omega male role under the same criteria, whose function would be to connect with the hierarchy of females and a scapegoat role, a very passive female receiving all kinds of attention from most subjects.