Overview

• Male white-faced capuchins on Jicarón Island have been observed abducting and carrying howler monkey infants, leading to the infants' deaths from lack of care.
• The behavior, first seen in 2022 with a male nicknamed 'Joker,' has spread to other young males through social learning and imitation.
• Over nearly two years, researchers documented 11 such abductions through extensive camera trap footage, with four infant deaths confirmed.
• Scientists suggest the behavior is driven by boredom in the resource-rich, predator-scarce environment, framing it as a non-functional cultural trend.
• The findings, published in the journal *Current Biology*, highlight parallels with other species' cultural quirks, though with lethal consequences in this case.