There’s strength in numbers.
In the wild, sometimes it pays to stick together.
In many species of animals, males tend to be aggressive and territorial toward members of the same sex.
But there are times when forming friendships provides an evolutionary benefit that going at it alone simply doesn’t.
Here are 6 animal bromances that show the value of friendship:
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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.
"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.”
Joseph Feldblum, study author and University of Michigan researcher
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It turns out these behaviors help them sire more young.
This is especially the case for those who are close with the alpha male of their group. That relationship can help chimps gain access to mating opportunities they wouldn’t have otherwise.
These male monkeys also form friendships to help climb the social ladder — and their motive might be similar to those of chimps.
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When males macaques bond together, they form coalitions that help them maintain their social standing or raise their status.
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.
And there’s actually an advantage for male birds to stick together rather than split off into monogamous pairs.
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An August 17 report published in Proceedings of the Royal Society B found that males living in groups with one or two others of the same sex produce more offspring over the course of their lives.
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The non-breeding males will help raise their pal’s offspring.
More care means a higher chance that those babies will one day become fully-fledged members of bird society.
The Florida Scrub-Jay also raises offspring in groups, allowing many hands — er, wings — to help their young reach adulthood.
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Male scrub jays, who are usually adult offspring from seasons past, will hang around the nest and help their parents care for the young until they find their own mate.
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In this cooperative breeding setup, male helpers can stick around for up to six years.
Power comes in numbers for these big cats.
Young males will form coalitions that can help them overthrow other males in power once they’re strong enough to fight.
Oftentimes, young male lions will band together with their biological brothers, and one will be in charge of the whole group.
When in moderately stressful situations, rats will bond with members of the same sex.
And these friendships might make them — and us — more resilient to future stress, according to a 2016 study.
Friendship bonds release oxytocin in the brains of both us and rats. In turn, we’re motivated to socialize more — a result that can make us more cooperative and empathetic in hectic times.
Read more stories about animals here.
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