Male bonding may help some monkeys fight the ill effects of everyday stress.
Usually when male primates live in groups with other males, the guys tend to fight over girls. But while studying wild Barbary macaques, scientists found that males with strong social ties to other males had lower stress hormones in their feces than males with weaker bonds. The results suggest that the stress-reducing benefit of friendship extends far beyond that seen among females and pair-living animals, the researchers report in the December 8 Proceedings of the National Academy of Sciences.