Social and Spatial Affinity Drive Wound Care by Ants

In group-living animals, open wounds pose a risk not only for the injured individual but also for the entire group, especially when the risk of infection transmission is high. To mitigate this danger, different species have developed diverse strategies - with ants representing one of the few taxa beyond humans that engage in social wound care. Yet, who provides this care and what determines its allocation remains unclear. To answer these questions, we combined controlled injury experiments with automated behavioral tracking across six colonies of the ant Camponotus fellah. Our results reveal that wound care is primarily provided by a non-specialized subset of individuals whose behavioral traits align with a transitional phase between the nurse and forager roles. Among these transitioning ants, care provision was best predicted by their prior spatial and social proximity to the injured individuals in the hours before the injury, indicating that pre-existing social affinity influences caregiving behavior. These findings offer the first empirical evidence of how caregivers are integrated into the colony's social structure and highlight the role of social interactions in shaping the organization of wound care in ants.