Dynamic adjustment of feeding behavior depending on dominant-subordinate relationship in large-billed crows.

Animals that forage socially adjust their behavior according to social status. Dominance and subordination are defined by priority of access to resources in competitive contexts. While dominant individuals can control access to resources, subordinates must obtain food through alternative strategies. In direct encounters with dominants, subordinates are expected to adjust their behavior to the partner on a moment to moment basis. However, the decision dynamics in such situations remain unclear. We tested large-billed crows in a dyadic feeding experiment to examine whether social status shapes feeding behavior. Using tracking analysis, we quantified the time series of approach velocity toward food and assessed whether its dynamics were modulated by the partners movements. Subordinates adjusted the velocity of their reaching movements. Specifically, a dominants approach increased a subordinates reaching speed, suggesting that subordinates accelerated to avoid aggression under dominance pressure. In contrast, this effect was weak or absent in dominants, indicating asymmetric social influences on foraging. Taken together, these findings suggest that subordinates fine tune the kinematics of feeding behavior in response to dominant movements, whereas dominants do not.