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 can include tailless primates taxonomically considered monkeys (such as the Barbary ape and black ape), 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, include four genera comprising three extant species of orangutans and their subspecies, two extant species of gorillas and their subspecies, two extant species of panins (bonobos and chimpanzees) and their subspecies, and one extant species of humans in a single extant subspecies. 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.