DISTRIBUTION: Argentina, Bolivia, Brazil and Paraguay.

DIET: Leaves and other plant parts, fruits.

NOTES: A member of the New World monkeys. These monkeys commonly sleep or rest up to 70% of the day. It lives in groups of 3 to 19 individuals. Named for their vocalizations, they may be heard most often around sunrise. The call can be heard up to 5 km away. The prehensile tail is very strong and acts as a fifth limb. They generally prefer walking and climbing to running or leaping.