King pong: Male monkeys cover themselves in their own urine to attract the ladies



It turns out male monkeys aren't taking the proverbial when it comes to their grooming habits and trying to catch a mate.

Scientists believe they can finally explain a baffling habit displayed by capuchin monkeys, who urinate on their hands and then rub the urine into their fur.

Male monkeys attract females by sending a message that they are single and available through rubbing urine into their fur, according to a study.



You smell lovely! A study suggests female capuchins are attracted to males who have washed themselves in their own urine

There is more activity in the brains of female tufted capuchins when they are exposed to the smell of the urine of sexually mature males, researchers said.

Several hypotheses for why they perform this 'urine wash' had been tested by earlier studies, but most had proved inconclusive.

Possible reasons that had been put forward previously included the possibility that it somehow helped to maintain body temperature or allowed the monkeys to use the smell to identify each other.

'But one study reported that when being solicited by a female, adult males increased their rate of urine-washing,' said Dr Kimberley Phillips.

Dr Phillips is an associate professor of psychology at Trinity University in San Antonio, Texas, who specialises in research that focuses on understanding the neurological and biological basis of primate behaviour.

Dr Phillips and her research team investigated this behaviour further, using magnetic resonance imaging (MRI) to scan the brains of female capuchins.

The study involved performing scans while the females were exposed to the urine of sexually mature adult males and that of juveniles.

'Female capuchin monkey brains react differently to the urine of adult males than to urine of juvenile males'

The females' brains became significantly more active when they sniffed the scent of urine produced by adult males compared to that from juveniles, according to the results, which were published in the American Journal of Primatology.

It is believed that the sexually mature adult males excrete higher levels of testosterone into their urine, and the females are able to detect this through smell.

Capuchin monkeys are native to Central and South America where they live with their offspring in mixed sex groups, usually headed by a dominant male.

The concentration of testosterone is also linked to their social status with higher status males tending to produce more of the hormone.

'Female capuchin monkey brains react differently to the urine of adult males than to urine of juvenile males,' said Dr Phillips.

'We suggest that this is used as a form of communication to convey social and or sexual status.'

A number of other monkey species have exhibited similar 'urine washing' behaviour, including mantled howler monkeys, squirrel monkeys, urinating into the palm of the hand, then vigorously rubbing the urine into the feet and hindquarters.

