Researchers say this is the first time this type of behaviour between the two species has been recorded.

With its sprawling cedar forests and abundant wildlife, the island of Yakushima is known for being so beautiful it inspired a Studio Ghibli animated film. Located about 60 kilometres (37.2 miles) south of Japan’s southern island of Kyushu, Yakushima is now attracting worldwide attention for a very different reason, and this time it involves a story about a monkey and some deer.

Footage filmed on the island late last year shows the two animals co-existing peacefully in the forest until suddenly, the monkey jumps on the deer’s back. Rather than looking to hitch a ride, though, the primate appears to be trying to sow his wild oats with the four-legged creature, in what’s being described as only the second-ever recording of sexual behaviour between two distant species, and the first between a monkey and a deer.

Take a look at the video below:

The video has been included as supplementary material for a research paper entitled Interspecies Sexual Behaviour Between a Male Japanese Macaque and Female Sika Deer, which was published in the journal Primates yesterday. According to researchers, deer and macaques enjoy a symbiotic relationship, with the primates being known to groom and even ride the deer as they forage for dropped fruits on the forest floor.

However, the sexual behaviour displayed by this one macaque, who was filmed mounting several deer, is believed to be unusual. While some deer didn’t seem to object to the monkey on their backs, others attempted to escape from its grip. The macaque never displayed any aggression towards the does in his midst, although he did chase away other male primates in the vicinity during one mount, in order to guard his perceived mate.

According to scientists involved in the research, the monkey pictured in the video was a low-ranking male. It’s theorised that the macaque’s behaviour was likely due to mate deprivation, as a result of there being limited access to females in the area.

Source: Net Lab
Featured image: YouTube/Cédric Sueur
Insert images: YouTube/Cédric Sueur