Range: Nigeria, Cameroon, Gabon, Congo; between the Congo & Niger Rivers

Diet: In the wild, mandrills consume fruits and seeds as primary diet items, but they also will eat insects (ants, termites, dung beetles), spiders, fish, crabs, tortoises, mice, frogs, birds, bird eggs and nestlings.

Fact File:

• Mandrills are the largest of all monkeys.
• The bright colors of a mature male might be useful when other troop members must locate him.
• Head bobbing is the most common way to communicate threat. (Rowe 142) Mandrills will sometimes "yawn", exposing their large canine teeth. Some scientists think this is "a sign of tension" within the troop (Rowe 142).
• "Males have a two-phase grunt or roar that mobilizes the group for traveling" (Rowe 142).

Mandrills belong to the Cercopithecidae family, the Old World Monkeys. Some characteristics of the Old World Monkeys include: a narrow nose and palate, flattened nails on the digits, cheek pouches, and ischial callosities, pads of thickened skin on the rear end that provide a weight bearing surface as the monkeys sit (Rowe 119).

In addition to the brilliant colors on their faces, males have coloration on their hind ends - light purple that fades into a reddish purple color. The pronounced differences in size and coloration between males and females are referred to as sexual dimorphism.

Male mandrills have large, menacing canine teeth that may be up to 2.5 inches long. The teeth are used in threatening facial expressions and as weapons. Mandrills also have cutaneous (skin) glands, including a sternal gland in the middle of the chest. "Males older than 7 years scent-mark, but alpha males scent-mark more frequently" (Rowe 142).

"Cheek pouches open beside the lower teeth and extend down the side of the neck; they can hold the equivalent of a stomach load of food, leaving hands and feet free for running and climbing", an important feature for a primarily terrestrial animal (Lincoln Park Zoo).

Social organization & behavior:

Mandrills live in dense forests where it is difficult to observe them. Therefore, they have never been extensively studied in their natural habitat and not much is known about their behavior in the wild.

Mandrills are primarily terrestrial (ground dwelling). However, females and juveniles often climb into trees to feed, and mandrills may sleep in trees.

Reports of troop size vary greatly from 2-250 animals. Large troops may represent the gathering of several smaller troops. Smaller troops (the basic social unit) are believed to consist of one large adult male, 5 to 10 adult females and 10 juveniles (Nowak 480). This type of organization is sometimes referred to as a harem. Other scientists cite the existence of multi-male groups (Aram vanHoff 252).

"The amalgamation into larger multi-male groups is evidently seasonal" and has to do with the efficiency of large versus small group sizes in finding food when it is either scarce (larger groups do better) or abundant (smaller groups fare better) (Aram vanHoff 252).