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 ...

Capuchin monkeys have been caught on camera abducting the babies of another primate. The "weird" fad, which led to the deaths of several baby howler monkeys, was started by a male capuchin named Joker ...

On a remote Panamanian island, researchers have observed for the very first time young male capuchin monkeys stealing howler monkey babies, according to a new study. Since 2017, researchers have used ...

A young male nicknamed Joker was probably the first to start carrying a howler monkey baby on his back for days on end. Then a group of other young males started to copy him. Here a white-faced ...

A capuchin named Joker started the apparent trend, leading researchers to suspect "there was something a little quirky about him, or that he was kind of lonely in a way.” Reading time 3 minutes A ...