Hamadryas baboons live in basic social units, which are structured like harems, with one male and up to five females and offspring (usually one infant, rarely twins). Two to three social units will unite to form groups called clans; clans will unite to form bands; and several bands will unite to form a troop. A troop will sleep and travel together in search of food.
Handy for travel, baboons have cheek pouches, in which they can store food to eat at a later time. In the wild, baboons feed on grasses, roots, tubers, fruits, nuts and vegetables, as well as eggs and sometimes small animals. They also have been known to raid crops and garbage dumps. In zoos, baboons eat primate chow, fruits, nuts and vegetables.
Baboons breed all year but breeding peaks May through June. Males stay with the natal unit/clan while the females will migrate to another clan or sometimes to another band. Since they are a monomale, polyfemale society, the harem master is the only breeding male. The female will present herself to the male as a signal she is ready to breed.
A young male staying with the natal unit may inherit the harem from his father. He may entice juvenile females from the other units into his clan or from other clans within this band and form his own harem. He may be accepted into another unit with an elderly harem master and serve as a “stud” while the older male remains the patriarch and leads the harem. If a female misbehaves, the male will give her a bite on the back of the neck.
Did you know? Adult males will emit a warning call that sounds like “wahoo” if predators are in the area. This call is also used to signal aggression. Sometimes when a baboon yawns it is considered a threat. Baboons have a low, soft grunt, which is used like a greeting. All Hamadryas, except the adult males, emit a sharp bark, which is an alarm signal at which all animals flee.