Baboons are only found in Africa. They are the best adapted of all monkeys to a terrestrial life, the Hamadryas being the most terrestrial. Baboons live in a wide range of habitats including open habitats. But they require rocky cliffs or tall trees to sleep in at night and access to water. Only a few are forest dwellers, such as the Guinea baboon from West Africa.
Baboons eat a wide variety of food, generally whatever is in abundance. Baboons have relatively long thumbs to dextrously pick and prepare food (e.g., peeling, stripping). They prefer fruit, but when this is not available, will eat less nutritious but abundant food. The Yellow baboon is particularly adapted to seeds with unusual chemistry which other creatures find less palatable. During the dry season, grass can make up 90% of their diet, tearing it up in handfuls. They may also dig up tubers and they can survive on roots and bulbs alone. Their long, dog-like jaws have large molars which efficiently grind up such tough food. They also have cheek pouches to stuff food into. This way, they can quickly gather their food, then slowly process it later in a safer and cooler place. Unfortunately, baboons also raid human crops.
Baboons eat a lot more meat than other primates. Mostly these are insects, snails and other invertebrates. But they also eat small mammals if they get the chance. They commonly kill and eat hares, birds, young antelopes and even fellow primates such as bushbabies and young vervet monkeys. Their large size also allows them to overcome and kill, when hunting in a group, larger prey such as gazelle kids. They have large impressive canines, their main weapons of defence and offence. Yellow baboons have been observed hunting down hares and digging out burrowing mammals. The chacma and olive baboon gorges on grasshoppers and scale insects when there are infestations of these insects, ignoring all other food. Olive baboons also hunt hares and larger mammals like vervet monkeys and infant gazelles. Those living on the coast may hunt molluscs, crabs and other marine life.
Baboons are active during the day. Their limbs are well adapted to running fast on all fours in a rocking horse gallop. They walk in an awkward swaggering manner. Although baboons spend most of their time foraging on the ground, they all retire in trees or high up on steep-sided cliffs to sleep, safe from predators like the leopard. So they can also climb well. In fact, the availability of safe sleeping sites is the limiting factor to troop size. Because their food is so sparsely distributed, baboons often travel long distances, about 6-20 km a day on a home range of up to 60 sq km. Because they share their sleeping site and often their foraging home ground too, baboons are not territorial, although subgroups avoid each other as they forage.
The Hamadryas baboon forms the largest troops. Unlike the other baboons, they have a complicated three-level social structure. The largest social unit is the troop which includes all those sleeping at a particular cliff. This averages 140, but can reach 750!
The troop, however, breaks up into smaller foraging bands in the morning of about 30-90. But even these can be large, one band was estimated at nearly 500! Within each band are several harems of one male and several females (up to 9) and their young. Males without harems may forage alone or in bachelor bands.
Sometimes the males of two or more harems will cooperate. Such cooperating harems form a clan. Males of the same clan will help defend each other from attempts by males from other clans to steal their females. While male juveniles leave the natal band, they usually stay in the same clan. Females, however, may leave the clan.
Within the Hamadryas band, females are preoccupied with gaining the favour of the dominant male, fighting among themselves to groom him. But they ignore females from other bands. The dominant male focuses on keeping his females from straying, and sometimes fight for possession of a female. Male combat involves rapid batting with hands and open jaws, but rarely result in actual all out fighting. Males also protect their harem from danger, bringing up the rear and putting up a defence, while females run off with the young.
To start his harem, a young Hamadryas male must steal a female from another band. He starts by walking between her and her mother, and when she begins to follow him, will keep her with him by using threats.
A young female is lured away at about 2 years old and the male guards her until she reaches breeding age at 5 years.
The other baboon species have a different social structure. Groups average 30-60 but vary between 8 and 198. The groups do not split up during the day but forage or rest as a single unit, although they may spread out on a broad front. Each group has many males and females, although usually more females.
All males are dominant to females. The males in the group compete for rank. High rank is obtained through fighting or by forming alliances with other males. Females have a less obvious hierarchy, but in some (Olive baboons), offspring inherit the rank of their mothers. High ranking males have first access to females in season. Subordinate males may also achieve mating success by ingratiating themselves with females by protecting them and their young. Although males and females are promiscuous, a male and female may form a long-lasting friendship.
The dominant male decides when and where to forage. Females are in front as they move, but it is the dominant male that directs them from behind. Females with young stay closer to the dominant male, subordinate females hang out with the subordinate males. Younger males may go ahead as look outs and sound the alarm when they see a threat. The adult males will then move forward to take charge.
Usually one young is born at a time. Babies first cling to their mother's chest, but later ride jockey-style (right). Young baboons stay with their mothers for up to 18 months, learning from her what and how to eat it.
Status and threats
The Hamadryas baboon was considered sacred by the ancient Egyptians, and were often depicted as the attendant to Thoth, the God of writing. Hamadryas baboons were allowed to range freely in temples. They were also mummified, and their images carved into temples. They are now extinct in Egypt. Baboons are hunted for their meat, as a pest, and for sport. Besides the Hamadryas, the other baboons are listed as "vermin" in the African Convention and hunted as pests. In the past, large numbers of Hamadryas baboons were trapped for medical research in the Soviet Union. Yellow baboons also suffered a similar fate. Their habitat is threatened as humans encroach further into their less hospitable habitats with improvements in