Conditions of observation and social distance in groups of squirrel monkeys,Saimiri sciureus

Observation conditions were very influential in determining the social distance among members of groups of squirrel monkeys. With observer visible to the animals and recording by talking into a tape recorder the monkeys did not show a consistent pattern of social distance as reflected by actual space and frequency of bodily contacts, whereas when the observer was concealed, looking through a one-way vision screen and recording silently by marking on paper, the subjects tended to group in unisexual clusters, with that of the females showing higher cohesiveness.