This is scientific Americans 60 second science. I'm Karen Hopkins.

Don't mess with a monkey because if you do he might take revenge on your family and friends.

That's according to a study of Japanese Macax,

which shows that monkeys keep track of each other's associates

and make use of that intel when it comes time for payback.

The findings are in the Royal Society Journal, Open Science.

Researchers were interested in the question of how primates suss out social relationships,

knowledge that can come in handy for maneuvering within a complex society.

To assess how the moccax obtain and make use of such social know-how, the researchers decided

to focus on episodes of aggression, a common feature of Simeon interactions.

They went through more than 500 hours of video recordings showing the exchanges that took place in a group of 57 Macax living in the Rome Zoo.

Monkeys whose genealogical ties are well known.

And they parsed some 15,000 episodes of aggression,

noting the relationships among the individuals involved.

First, they confirm that monkeys that find themselves at the receiving end of aggression

tend to turn around and take it out on a third party.

And that retaliation is often directed at a relative of the

original aggressor but how do the monkeys determine who's kin well one way would

be that they've been around long enough to have watched each other grow up.

But that doesn't seem to be the case.

When researchers look specifically at conflicts involving older monkeys, it didn't seem that relatives were singled out for revenge.

What does seem to be true is that victims will target their attackers associates, the other monkeys

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