A baby howler monkey clung to the back of an older male monkey, its tiny fingers grasping fur. But they're not related and not even the same species. Scientists spotted surprising evidence of what ...

Howler infant number 5 on the back of a juvenile capuchin carrier, who is using stone tools at an anvil site in a stream bed. Usually, this behavior in females is described as adoption, thought to be ...

Capuchin monkeys on a remote Panamanian island are abducting babies from howler monkey families, in a first-of-its-kind trend. The wild population of white-faced capuchins (Cebus capucinus imitator) ...

Observations of Coiba’s tool-using immature capuchin monkeys show them carrying abducted infant howler monkeys. What is the reason for this behavior? Vanessa Crooks Caught in the act! Capuchin monkeys ...