On an island in Panama, a fad that one researcher called "viscerally disturbing" has recently taken off among a group of young male monkeys. These adolescents and juveniles have started to kidnap the ...

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 ...

Quiet on the tee? The howler monkeys weren’t having it. Hidden in the canopy above me, the loudest mammals on the planet were holding forth in full-throated violation of golf etiquette: primates with ...

Brown howler monkeys (Alouatta guariba), endemic to the Atlantic Forest in Brazil and Argentina, became one of the 25 most threatened primate species following a yellow fever outbreak in late 2016. In ...