Baboons are African and Arabian Old World monkeys belonging to the genusPapio, part of the subfamily Cercopithecinae. The five species are some of the largest nonhominoid members of the primate order; only the mandrill and the drill are larger. Previously, the closely related gelada (genus Theropithecus) and the two species (mandrill and drill) of genus Mandrillus were grouped in the same genus, and these Old World monkeys are still often referred to as baboons in everyday speech. They range in size and weight depending on species. The Guinea baboon is 50 cm (20 in) and weighs only 14 kg (30 lb) while the largest chacma baboon can be 120 cm (47 in) and weigh 40 kg (90 lb).
The hamadryas baboon (Papio hamadryas) is a species of baboon from the Old World monkey family. It is the northernmost of all the baboons, being native to the Horn of Africa and the southwestern tip 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. The hamadryas baboon was a sacred animal to the ancient Egyptians and appears in various roles in ancient Egyptian religion, hence its alternative name of 'sacred baboon'.