Mandrills are easily recognized by their olive-colored fur and colorful faces and rumps (though females have duller colors). They also don't have long tails.
- "No other member in the whole class of mammals is colored in so extraordinary a manner as the adult male mandrills."
- —Charles Darwin
Mandrills are native to southern Cameroon, Gabon, Equatorial Guinea, and Congo. They are mainly found in tropical rain forests and occasionally woodlands. They are omnivores, but prefer plants over meat since it is easier to access. Mandrills mostly eat invertebrates, such as ants, beetles, termites, crickets, spiders, snails, and scorpions. They will also eat eggs, and occasionally vertebrates, such as birds, tortoises, frogs, porcupines, rats, and shrews.
Like lions, mandrills are social creatures and live in large groups (one is recorded to have had over one-thousand individuals). These groups are called "hordes" and are led by one dominant male. Their mating season takes place from June to October. They breed every two years. Because of this rapid rate in birth, mandrills have a long life span; they can survive up to forty years in captivity.
Males weigh fifty to eighty pounds (some growing to be over one-hundred) and females are usually half that weight, around twenty to twenty-four pounds. The average male is eighty-one to ninety centimeters long (thirty-two to thirty-six inches) and the female is usually fifty-six to sixty-six centimeters long (twenty-two to twenty-six inches), with the tail adding another five to eight centimeters (two to three inches). Overall, the mandrill is the world's largest species of monkey.