© 1982 by The Society for Integrative and Comparative Biology
Recognition of Individuals Within and Between Groups of Free-Ranging Vervet Monkeys1
Rockefeller University Field Research Center Millbrook, New York 12545
SYNOPSIS. The ability of animals to recognize and classify others reflects the selective pressures acting on individuals within a particular social framework. Data on recognition therefore allow us to consider social structure from the animal's point of view. Here we review data on recognition within groups of free-ranging vervet monkeys, and present evidence of recognition across groups. Within groups, experiments suggest that animals may proceed beyond simple discriminations of kin and non-kin to create a taxonomy in which group members are both distinguished as individuals and grouped into higher order units, apparently on the basis of matrilineal kinship. Across groups, observation indicates that male transfer is non-random, and that the exchange of males between groups is correlated with reduced aggression. Playback experiments demonstrate that monkeys associate the vocalizations of particular individuals with particular groups. We conclude that the social organization of vervet monkeys is best regarded as a "community" of groups, within which individuals recognize each other and share a high degree of genetic relatedness despite the maintenance of otherwise discrete social units.