Ava the spider monkey decided to go on a stroll without her owner in South Carolina. Her caffine addiction cut her escape short. Watch.

FARGO — A pair of critically endangered monkeys are settling into their new home at the Red River Zoo. Critically endangered pied tamarins Noah and Peanut Butter explore their new home Thursday, Aug.

Believe it or not, primates may have invisible hands as well as opposable thumbs. New research published this month (registration required) in the journal Proceedings of the National Academy of ...