 Monkey’s unusual behaviour is only the second recorded observation of sexual interaction between distantly related wild animals 
 
 A male snow monkey has been observed attempting to have sex with female sika deer on Japan’s Yakushima Island, in an unusual example of interspecies mating behaviour. Snow monkeys and sika deer generally have a symbiotic relationship, with the deer eating fruits dropped from the trees by the monkeys and the monkeys grooming the deer and occasionally riding on their backs. The latest paper, published in the journal Primates, describes how a low-ranking male monkey was observed repeatedly performing sexual mounts on at least two different female deer. Marie Pelé, the lead author based at the University of Strasbourg in France, said: “No ambiguity is possible, it is clearly sexual behaviour.” 
 
 The only previous reported case of sexual interactions between two distantly related species, was that of an Antarctic fur seal observed sexually harassing king penguins – and in one instance, eating a bird after having sex with it. “He was therefore probably either peripheral or belonged to a group of peripheral males, as other males were observed in the vicinity of the deer.” 
 
 The monkey was also seen guarding the target of his affection and chasing away other male monkeys who came near. “The most realistic hypothesis would be that of mate deprivation, which states that males with limited access to females are more likely to display this behaviour,” the researchers conclude.
– One lonely snow monkey in Japan is taking animal sexuality to strange new places. In a study published Tuesday in Primates, researchers documented a monkey having or attempting sexual relations with at least two sika deer. While one of the deer ran off, the monkey mounted another deer and ejaculated on its side, Gizmodo reports. According to the BBC, a co-author of the study says the act "included about 15 sexual movements over a period of 10 seconds." While sex between closely related species does happen, this is only the second time a sexual act between two distantly related species has been recorded, the Guardian reports. (The first was in 2006, involving an Antarctic fur seal and a penguin.) Snow monkeys and sika deer have had an up-until-now platonic relationship. Deer eat fruit dropped by the monkeys (as well as their poop), while the monkeys groom the deer and sometimes ride on their backs. In this case, however, the monkey was displaying "clearly sexual behavior," including chasing other monkeys away from the deer, notes the study. Researchers are blaming "mate deprivation," theorizing that the monkey—who has low social status—was suffering from "limited access to females." The incident happened during snow monkey breeding season. (Meanwhile, a North Korean zoo has a smoking chimp.)