Colorful guenon monkeys
Guenon monkeys are one of the most diverse groups of Old World monkeys. Recently, researchers discovered that their incredibly intricate facial patterns help the sociable monkeys avoid interbreeding with other guenon species.
There are more than 30 different guenon monkey species, such as the Erythrocebus patas shown here.
Guenon monkeys forage in large groups, with two to six different species traveling together for added protection.
Cheek pouch monkeys
Guenons are also called cheek pouch monkeys, as shown by this Miopithecus talapoin. They stuff fruits, leaves and insects in their cheeks.
Each guenon monkey resembles other members of its own group, but is strikingly different from other species.
The different facial fur patterns helps guenon monkeys avoid interbreeding.
When guenon monkeys interbreed, their offspring may be infertile or less healthy, such as when horses and donkeys breed.
Each guenon species communicates via unique chirps, calls and whistles.
Guenons live in the forests of Central and West Africa.
An amazing set of guenon faces.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.