Leopard predation on wild Sichuan snub-nosed monkeys

Predation is widely recognized as a powerful selective pressure on primate behavior and ecology, although knowledge of predator–prey relationships remains limited partly due to the rarity of directly observed attacks on primates. Here, we describe four confirmed or suspected instances of leopard ( Panthera pardus ) predation on free-ranging Sichuan (golden) snub-nosed monkeys ( Rhinopithecus roxellana ), a highly endangered colobine species endemic to China. We recorded predation events and the reactions of monkey group members. We suggest that the evolution of a multilevel society may be an adaptive response by Sichuan snub-nosed monkeys to the risk from leopards as well as other potential predators, one that balances the pressures of predation and intra-species competition and conflict.