Overview

• White-faced capuchin monkeys on Jicarón Island have been observed abducting and carrying baby howler monkeys, a behavior not seen in any other known primate population.
• The behavior originated with a single male capuchin, nicknamed 'Joker,' in January 2022, and spread to four other young males over 15 months, involving 11 howler infants.
• The abducted howler infants, all under four weeks old, clung to their captors but ultimately died of malnutrition as the capuchins could not provide milk.
• Scientists describe this behavior as a socially learned cultural fad, potentially driven by boredom in the predator-free environment of Jicarón Island.
• The study highlights conservation concerns, as repeated infant losses could exacerbate the decline of the endangered howler monkey population on the island.