SOCIAL-BEHAVIOR OF WILD MOUSTACHED TAMARINS, SAGUINUS-MYSTAX, AT THE ESTACION-BIOLOGICA-QUEBRADA-BIANCO, PERUVIAN AMAZONIA

The social behavior in two small, polyandrous groups of moustached tam arins, Saguinus mystax, was studied at the Estacion Biologica Quebrada Blanco in northeastern Peru. Allogrooming was the most obvious type o f social interaction. Grooming relations were characterized by a stron g asymmetry. In both groups, one adult male contributed about 70% of a ll allogrooming given (in terms of time spent grooming) and allocated his allogrooming evenly to all other group members. Grooming relations between the second adult male and other group members were less inten sive. Intragroup agonistic interactions were infrequent, and most of t hem occurred in the context of feeding on small food resources (fruit, exudate) and during intergroup encounters. Sexual behavior was rare, but at least in one group a tendency existed for the principal groomer to be somewhat more active than the other male. Results are compared with data from other field studies on callitrichid social behavior. Al though the label polyandrous correctly describes the demographic struc ture of many groups, it is not clear whether it is sufficient for unde rstanding the patterning of social relations and thus the social organ ization of tamarins. (C) 1996 Wiley-Liss, Inc.