Breaking up is hard to do -- and can be detrimental to one's reproductive fitness, according to a new study. Focusing on wide-eyed, nocturnal owl monkeys, considered a socially monogamous species, the ...

Scientists caught a male Japanese macaque red-butted (so to speak) trying to mate with several female sika deer. In the video, a few of the deer try to shake the little monkey off, but others just ...

Some monkeys in Gombe National Park don't seem to mind if the monkey they're mating with is not their own species. Instead, "promiscuous" red-tailed and blue monkeys are coming together and making ...

A male monkey in Japan has been filmed trying to mate with a female deer—likely the first observation of two distantly related species having a nonviolent sexual encounter. Japanese macaques and sika ...

A new study of guenon monkeys in Gombe National Park is the first to provide genetic evidence of ongoing mating between two distinct species. These monkeys have successfully been producing hybrid ...

A male Japanese monkey has been filmed trying to mount and mate with a Sika deer. Researchers saw the primate attempting to mate with at least two deer in November 2015, during the macaque breeding ...

The randy apes have been at it with other species for hundreds, maybe thousands, of years, say researchers SEX-mad monkeys have been bonking off with other species, creating an entirely new hybrid ...

One of Africa's rarest monkeys likely interbred with baboons in its past, new genetic research suggests. The large monkey called Rungwecebus kipunji, or kipunji for short, was only discovered in 2003, ...

You’ve heard the saying: Size matters. Of course, it depends on what you’re talking about — and whom you’re talking to. But for male proboscis monkeys from Malaysia, it turns out that having a bigger ...

The macaque attempted to mate with at least two Sika deer A male Japanese monkey has been filmed trying to mount and mate with a Sika deer. Researchers saw the primate attempting to mate with at least ...