Primates May be More Likely to Cooperate than to Compete

Arguing against the portrayal of primates -- whether human or not -- as primarily aggressive and competitive, two researchers on a panel at the AAAS Annual Meeting said instead that primates are much more likely to be nice to each other. Reviewing 86 studies of how primates spend their waking hours, Robert Sussman, of Washington University in St. Louis, MO, and Paul Garber, of the University of Illinois, Urbana, found that the animals spent an average of one percent of the time being aggressive. Cooperative behavior was 10 to 20 times more common.

Photo courtesy of Ian C. Gilby

"All primates live in social groups and have to give up some freedoms in order to do so," Sussman said. "But contrary to what is believed, cooperative, affiliative behavior is much more prevalent than aggression."

Many primatologists believe that self-sacrificing behaviors among primates is a response to "undo" social damage inflicted during conflicts, but Sussman and Garber contend that such behaviors are beneficial to primates in other ways. For example, the "helper" tamarind male, who babysits his mother's younger offspring, may be making himself more welcome in his grouping, and natural selection could thus favor cooperative behavior.

According to panelist Karen Strier, of the University of Wisconsin, Madison, the helper primates who gain experience caring for the offspring of other primates are in turn better parents, and are more likely to have healthy offspring themselves.

Sussman and Garber called for a new way of viewing primate behavior, suggesting that "competition over food and mates may not be directly responsible for driving sociality. They argue that their colleagues have been wrong in assuming that groups of primates rapidly grow beyond a manageable size, and that, therefore, fights over access to food are common. Instead, Garber and Sussman point to evidence that small groups of primates break off from the larger group in a process called "fissioning."

"Overall," they concluded, "we see no empirical justification for elevating competition and aggression as sovereign or more important behavioral tactics than affiliation."

-- Coimbra Sirica