It is the northernmost of all the baboons, being native to the Horn of Africa and the southwestern region of the Arabian Peninsula.

These regions provide habitats with the advantage for this species of fewer natural predators than central or southern Africa where other baboons reside.

[6] The hamadryas baboon shows differences in coloration among adults with males having a pronounced silver-white mane and mantle, which they develop at around the age of ten years, while the females are capeless and brown all over and have reddish to dark brown faces.

[9] The hamadryas baboon's range extends from the Red Sea in Eritrea to Ethiopia,[5] Djibouti and Somalia.

During the wet seasons, the baboon feeds on a variety of foods, including blossoms, seeds, grasses, wild roots, bark and leaves from acacia trees.

Hamadryas baboons also eat insects, spiders, worms, scorpions, reptiles, birds, and small mammals, including antelope.

[12] The hamadryas baboon has an unusual four-level social system called a multilevel society.

[19] Bands may fight with one another over food or territory, and the adult male leaders of the units are the usual combatants.

[21] The males limit the movements of the females, herding them with visual threats and grabbing or biting any that wander too far away.

[21][16] Females can still associate and help their extended families despite their interactions being controlled by the harem males.

The harem males suppress aggression between the females and prevent any dominance hierarchies from arising.

[23] Because bipedalism is thought to help reduce thermoregulatory stress, research has investigated how baboons deal with water restriction and thermal loads as quadrupeds.

[29] Using implanted data loggers and simulated desert conditions, researchers found baboon internal temperatures increased significantly with water deprivation.

[29] However, baboons can maintain their plasma volume during water deprivation due to an increase in blood colloid osmotic pressure (COP).

Hamadryas baboons often appear in ancient Egyptian art, as they were considered sacred to Thoth,[10] a major and powerful deity with many roles that included being the scribe of the gods.

A predynastic precursor to Astennu was Babi, or "Bull of the Baboons", a bloodthirsty god said to eat the entrails of the unrighteous dead.

Babi was also said to give the righteous dead continued virility, and to use his penis as the mast of a boat to convey them to the Egyptian paradise.

Sometimes, Thoth himself appears in the form of a hamadryas (often shown carrying the moon on his head), as an alternative to his more common representation as an ibis-headed figure.