Northern muriquis, which live in the Atlantic forest of Brazil, are one of the most endangered species of monkey in the world. To better understand what goes on in the mating lives of muriquis, ...

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 ...

Source: Sofya Dolotovskaya, used with permission. Many birds and mammals are socially monogamous—males and females pair up, live together, and often raise their young together. However, once methods ...