Beginning of Essay
In general, any member of the mammalian order Primates, with the exception of the tree shrews, the lemurs and their allies, the gibbons and apes, and humans. Monkeys are arranged into two main groups: those of the Old World tropics, the catarrhines, with two famil ....

Middle of Essay
.... drills). The hands and feet are prehensile, with, typically, five digits on each, the first (thumb and big toe) being divergent from the others. Commonly, the digits have flattened nails, but those of the marmoset are an exception. Except for the night-roaming durukuli of tropical America, monkeys are active during the day, moving frequently in bands in search of vegetation, birds' eggs, smaller animals, or insects to eat. Monkeys are highly social animals and are often organized in clans headed by an old male; these clans are rigidly defined in such species as howlers and baboons. As in all primates the brain is comparatively large. This feature, ....