From waiting to moving: how golden snub-nosed monkeys facilitate a group departure

Collective decision-making in animal societies requires effective coordination among members, in which individuals must adjust their behavioral rhythms to minimize consensus costs and maintain efficient coordination; otherwise, groups risk fragmentation and lose the benefits of collective living. Understanding the mechanisms of collective movements in a specific species is crucial for analyzing animals’ behavior, social organization, and ecological outcomes related to environmental adaptation. In this study, we investigate collective movement in socially tolerant golden snub-nosed monkeys (Rhinopithecus roxellana) within a multilevel society. Based on 306 observations of post-provisioning group movement events, each including a pre-departure phase and a subsequent departure, from five habituated one-male units (OMUs) in the Qinling Mountains, central China, we present how the behaviors of pre-departure initiators influence collective movement. The pre-departure initiators typically pause at the periphery of the provisioning area before initiating departures. We specifically demonstrate how this waiting behavior can affect both decision success and the duration of group departures. The results indicate that although individuals can initiate departures alone, those who wait and attract more voters are more likely to achieve successful group departures. Furthermore, the more members are ready to leave, the less time is required for group departures, suggesting that waiting behavior may facilitate group cohesion during collective movement. Such findings indicate that pre-departure initiators’ waiting behavior can shape consensus formation and enhance cooperation among group members.