howler monkey

Widely distributed large Central and South American monkey. Howler monkeys are tree-dwelling and feed on fruit and leaves. They have a prominent, hairless face and deep jaw, and the tail is long and prehensile.

Howler monkeys howl at dawn to demarcate territory. The howling is produced by the unusually developed egg-shaped hyoid bone at the upper end of the wind-pipe, in a swelling beneath the chin; the whole forms a hollow, resonant soundbox.

Classification Howler monkeys are in genus Alouatta, family Cebidae, order Primates.