London, June 17 A new study has shown that male and female baboons form platonic friendships. But while the females clearly benefit, it is a mystery what males get from such relationships.

In the study, researchers found that having a caring friend around appears to benefit the females and their infants, as both are harassed less by other baboons when in the company of their male pal.

However, why the males choose to be platonic friends remains a mystery.

"We don't really know what males or females get from these friendships. Males should be off trying to get other females to mate with them, not squandering their time on a female with a young infant," the BBC quoted Nguyen as saying.

The study also suggests that male baboons may be able to innately recognise their offspring.

Primatologist Nga Nguyen, an assistant professor at California State University Fullerton, and colleagues decided to investigate the occurrence of 'platonic' friendships in four groups of yellow baboons living in Amboseli, Kenya.

They studied the behaviour of more than 500 male and females in the four groups, and used genetic tests to determine the paternity of 183 of the baboons, including 23 young infants being cared for by a mother and her chaperone.

Half of all the male chaperones did turn out to be the father of the infant whose mother they befriended. That is highly surprising in one respect, because each of the females mated with multiple males around the time they conceived.

"But of these potential dads, only the genetic dads became friends. To my knowledge, human males cannot tell their own offspring from unrelated offspring, but somehow baboon dads can tell," said Nguyen.

However, the study also found that "half of the friends were not genetic fathers. But these guys weren't even potential fathers, that is, they didn't even mate with the female when she conceived the infant, and these guys didn't receive mating benefits."

"So we really don't know what these guys got out of the friendship, other than maybe spending time with a mum and a new baby and having other females seeing this," Nguyen said.

The researchers believe that by chaperoning a female in a platonic relationship, a male might advertise his parental skills to other females, who then might consider him a worthy partner.

But as yet, there's no evidence for this or any other reason why males become chaperones.

However, for the females, the benefits of having a chaperone are clear.

"We found direct evidence that friendships provided a social benefit to mothers and infants. We found that mother-infant pairs who spent a lot of time with their male friends received a lot less harassment from other females in the group, and the infants cried a lot less too, than pairs who spent less time hanging out with their male friends," Nguyen said.

The study has been published in Behavioral Sociobiology and Ecology. (ANI)