午夜福利1000集合

Just monkeying around? Adolescent female monkeys mount deer and rub themselves on the deers鈥� backs, apparently to practise sex when they are too young to be chosen by adult males.

Earlier this year, researchers reported observations of a single male Japanese macaque mounting sika deer and trying to mate with them.

In Minoo, Japan, researchers started recording monkey-deer liaisons in 2014, but there, it鈥檚 female macaques that have been observed mounting the deer. No毛lle Gunst and colleagues at the University of Lethbridge, Canada, recorded five adolescent female macaques mounting deer a total of 258 times in a two month period.

In the same group of monkeys, adolescent females are sometimes seen mounting other females or males and soliciting them for sex. These relationships, known as consortships, are thought to be a way to practise and develop adult sexual behaviours. Gunst even claims the female monkeys experience sexual reward through genital stimulation by mounting other monkeys.

Not now, deer

Gunst believes the deer-mounting behaviour is related. It has only been seen during the mating season and her observations show that the form and frequency of monkey-deer interactions are similar to their consortships with other monkeys.

Female monkeys were often seen rubbing their genitals on the back of the deer. In addition to mounting deer, the monkeys would gaze at them and emit high-pitched vocalisations like their typical oestrus calls. When deer walked away from them, the female monkeys sometimes displayed what Gunst characterises as 鈥渟exually motivated tantrums鈥� which consisted of crouching on the ground, body spasms and screaming, while gazing at the deer.

It was almost always adult male deer that allowed the monkeys to mount them. Females and younger males would usually rear up to throw the monkey off. Monkeys would sometimes groom the deer, which might explain why some deer were happy to be mounted.

Frustrated youth

Gunst thinks the most likely explanations for the monkeys鈥� behaviour is that they are practising sexual behaviours that take time to develop. 鈥淚t is well known that a period of maturation and practice is necessary for the development of adult-like sexual behaviors and sexual partner preferences in non-human primates,鈥� she says.

A contributing factor is that adolescent females are not the preferred partners of adult male monkeys, and tend to be rejected. Consequently, they may seek sex with deer 鈥渁s an outlet for sexual听frustration,鈥� says Gunst.

C茅dric Sueur at the University of Strasbourg, France, who reported on the male macaque mounting deer, agrees with this explanation. 鈥淚 don鈥檛 think this is a unique isolated case,鈥� he says.

Journal reference: Archives of Sexual Behaviour, DOI:

Read more:

Wild monkey filmed mounting deer and trying to have sex with it

New monkey species revealed thanks to distinctive penis

听