The 'higher' primates, the monkeys and apes, form a clade, the Anthropoidea ('human-like'), which is made up from two groups that evolved separately in the New World (mainly South America) and the Old World (Africa, Asia, Europe). The New World monkeys, the platyrrhines (literally 'broad nose'), have broadly spaced nostrils that face forwards, and some have a prehensile tail. The catarrhines (literally 'hooked nose'), or Old World monkeys and apes, have narrow snouts and non-prehensile tails.

Anthropoids share numerous characters, such as rounded nostrils, instead ofthe slit-like nostrils seen in other primates. The canine teeth are usually large and they occlude with the opposite canine and first premolar, the premolars are rather molar-like and the molars are broad and square.

The origin of anthropoids is hotly debated: the traditional view is that the clade originated in Africa, but a new proposal is that they arose in Asia (see Box 11.2).

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