It's a group of medium-sized African monkeys. Mangabeys range in color from fawn, or light brown, to black. There are nine species. One, the sanje mangabey, was discovered as recently as 1989 in Tanzania's Uzungwa Mountains. There are mangabeys across Africa's central belt, from Sierra Leone to Nigeria, Zaire and Kenya.
Mangabeys use their faces like people do - to show how they feel.
They have a white pigment on their eyelids, between the brow and the upper lid. So when they raise an eyebrow, other monkeys can see the threatening gesture really well. Like chimpanzees, they also bar their teeth, another aggressive gesture. And they smack their lips, which may mean they want to be groomed. Or it may be their way of showing respect to a more dominant monkey.