Solving the Collective action problem during intergroup encounters: the case of black and gold howlers (Alouatta caraya).

KOWALEWSKI, M MARTIN; GARBER, PAUL A

Howler Monkeys: Behavior, Ecology and Conservation.

Springer Press

Lugar: New York; Año: 2015; p. 413 - 428

Growing evidence from fi eld studies highlights the importance of social affi liation, social bonds, and cooperation in understanding primate behavior and social structure. In several platyrrhine species, intersexual and intrasexual cooperation and tolerance in the form of dyadic and group-level social interactions are reported to serve a critical role in the ability of individuals to obtain access to mates, effectively patrol and defend home ranges and feeding sites, and increase offspring survivorship. Howler monkeys constitute an instructive model for testing hypotheses concerning the costs and benefi ts of collective action as they usually live in cohesive social groups composed largely of unrelated or distantly related adults. We explored evidence of collective action focusing on Argentina black and gold howlers (Alouatta caraya ). We investigated the participation of individually recognized resident adult males in howling, vigilance, and fi ghting bouts during intergroup encounters, an event during which extragroup males (either lone males or males from neighboring groups) attempt to enter established groups and mate with resident females. During these encounters, some or all resident adult males responded by howling and approaching the intruder. Based on data on individual male participation during intergroup encounters, we argue that the collective action of several males benefits both actors and other group members by reducing opportunities for extragroup male takeovers, infanticide, and social disruption in established groups. Individuals may adjust their participation during these encounters in order to reduce the costs and enhance the benefi ts of collective action in maintaining reproductive access to resident females. We suggest that intergroup encounters are platforms where collective action problems may arise, are negotiated, and are solved through joint actions by central males and noncentral males. We also present limited data on male collective action in other howler monkey species.