Howler monkeys use play to avoid conflict, says study

We all know playing with friends is better than falling out, well it seems that some monkeys use play as a way of avoiding conflict.

A new study suggests howler monkeys use play as a way to reduce tension around food.

Researchers looked at seven different groups of howler monkey in Mexico and Costa Rica.

They noticed that the adult monkeys played more with each other than the children.

They also observed that play increased with the amount of time foraging for fruit, an activity which usually brings about conflict.

Howler monkeys usually eat leaves and the researchers say fruit is a "prized-resource" which the monkeys sometimes compete over.

The researchers believe that play, which uses a lot of energy, is being used to keep the peace.

Howler monkeys typically eat leaves

The study, carried out by a team of researchers from Spain, Brazil and the UK, focuses on the activity of two subspecies of howler monkey - the howler Mexican and the golden-mantled howler - in the rainforests of Mexico and Costa Rica.

Play for howler monkeys involves hanging from their tails and making facial expressions and signals to each other, like shaking their heads.

Co-author Dr Jacob Dunn, Associate Professor in Evolutionary Biology at Anglia Ruskin University (ARU), said: "We found that levels of play are at their highest when howler monkeys are feeding on fruit - which is a valuable and defendable resource."

Lead author Dr Norberto Asensio, of the University of the Basque Country in Spain, said: "One theory for the positive effect of fruit consumption on play is that a fruit-based diet simply provides the howler monkeys with more energy compared to their typical diet of leaves.

"However, if this was the case, we should have observed adults engaging in more play with all members of the group during fruit foraging, rather than just with other adults."

Unlike some primates who groom each other to keep groups together and reduce tensions, howler monkeys don't engage in collective grooming.

The researchers believe play is used by howler monkeys as an alternative way of keeping the group together.