Each bar represents a the average difference in the probability of interaction calculated as: (P(y)|closekin = 1) – (P(y)|closekin = 0) for “closekin”, and (P(y)|ritual = 1) – (P(y)|ritual = 0) for “ritual relationship”. Probabilities are calculated by averaging values over all dyads while keeping closekin or ritual fixed at 1 or 0, and t = 1. Dark bars represent Ache, light bars represent Hadza.