Infants infer third-party social dominance relationships based on visual access to intergroup conflict.

During a conflict, having a greater number of allies than the opposition can improve one's success in a conflict. However, allies must be aware that has a conflict has occurred, and this is often influenced by what they are able to see. Here, we explored whether infants' assessment of social dominance is influenced by whether or not social allies have visual access to an episode of intergroup conflict. In Experiment 1, 9-12-month-olds only expected an agent to be socially dominant if their allies were able to witness the conflict. Experiment 2 provided further support for this finding, as infants did not expect an agent from a numerically larger group to be socially dominant when allies were unable to witness the conflict. Together, these results suggest that infants do not simply use a heuristic in which "numerically larger groups are always more dominant". Importantly, infants are able to incorporate social allies' ability to witness a conflict when predicting social dominance between groups.