There’s strength in numbers.
Male chimps regularly participate in friendly behaviors toward each other — even when they have competition for mates. Research published August 17 in the journal iScience finally nails down why.
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"Chimps cooperate frequently, and often in these very dramatic ways: You see things like grooming, all kinds of complex alliance formation, and group territorial defense.”
These male monkeys also form friendships to help climb the social ladder — and their motive might be similar to those of chimps.
A 2010 report in Current Biology found that the strength of male bonds directly correlated with how many offspring they produced.
Even in the wild, friends help friends out.
The acorn woodpecker is known for its polygamous breeding habits, in which several birds will live together and raise chicks.
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Oftentimes, young male lions will band together with their biological brothers, and one will be in charge of the whole group.
And these friendships might make them — and us — more resilient to future stress, according to a 2016 study.