Apes (Hominoidea) are a branch of Old World tailless simians native to Africa and Southeast Asia. They are the sister group of the Old World monkeys, together forming the catarrhine clade. They are distinguished from other primates by a wider degree of freedom of motion at the shoulder joint as evolved by the influence of brachiation. In traditional and non-scientific use, the term "ape" excludes humans, and is thus not equivalent to the scientific taxon Hominoidea. There are two extant branches of the superfamily Hominoidea: the gibbons, or lesser apes; and the hominids, or great apes.

The family Hylobatidae, the lesser apes, include four genera and a total of sixteen species of gibbon, including the lar gibbon and the siamang, all native to Asia. They are highly arboreal and bipedal on the ground. They have lighter bodies and smaller social groups than great apes.
The family Hominidae (hominids), the great apes, includes three extant species of orangutans and their subspecies, two extant species of gorillas and their subspecies, two extant species of chimpanzees and their subspecies, and one extant species of humans in a single extant subspecies.[1][a][2][3]

Except for gorillas and humans, hominoids are agile climbers of trees. Apes eat a variety of plant and animal foods, with the majority of food being plant foods, which can include fruit, leaves, stalks, roots and seeds, including nuts and grass seeds. Human diets are sometimes substantially different from that of other apes due in part to the development of technology and a wide range of habitation. Humans are by far the most numerous of the ape species, in fact outnumbering all other primates by a factor of several thousand to one.

Most non-human hominoids are rare or endangered. The chief threat to most of the endangered species is loss of tropical rainforest habitat, though some populations are further imperiled by hunting for bushmeat. The great apes of Africa are also facing threat from the Ebola virus. Currently considered to be the greatest threat to survival of African apes, Ebola is responsible for the death of at least one third of gorillas and chimpanzees since 1990.[4]

Dixson, A.F. (1981). The Natural History of the Gorilla. London: Weidenfeld & Nicolson. ISBN 978-0-297-77895-0, p. 13
Grehan, J.R. (2006). "Mona Lisa Smile: The morphological enigma of human and great ape evolution". Anatomical Record. 289B (4): 139–157. doi:10.1002/ar.b.20107. PMID 16865704
Benton, Michael J. (2005). Vertebrate palaeontology. Wiley-Blackwell. ISBN 978-0-632-05637-8. Retrieved 10 July 2011, p. 371
Rush, James (23 January 2015). "Ebola virus 'has killed a third of world's gorillas and chimpanzees' – and could pose greatest threat to their survival, conservationists warn". The Independent. Archived from the original on 30 March 2015. Retrieved 26 March 2015.