White-faced Capuchin

White-faced capuchins demonstrate sophisticated coalition politics rivaling their Old World counterparts. Males form long-term alliances that persist for years, with coalition partners supporting each other in conflicts at rates exceeding 70%. What makes capuchin coalitions particularly instructive is their transparency: researchers can observe the entire decision-making process as males weigh the costs and benefits of intervention in real-time.

The reciprocity mathematics are precise. Capuchins track favors with remarkable accuracy, returning support to allies within a narrow band of proportionality. A male who receives coalition support but fails to reciprocate sees his alliance value decline rapidly. Within 6-12 months, unreliable partners find themselves isolated during conflicts. The memory window extends years, suggesting these primates maintain something analogous to a social credit score.

Food sharing provides another reciprocity channel. Dominant capuchins tolerate subordinates taking food, but this tolerance correlates strongly with the subordinate's coalition support history. Males who fight alongside dominants gain feeding privileges; those who defect lose access. This creates a multi-currency economy where fighting support and food access trade against each other.

For organizations, capuchins illustrate how coalition dynamics operate even without chimpanzee-level cognitive sophistication. The fundamentals—tracking reciprocity, punishing defectors, rewarding loyal allies—appear to be convergent solutions to the problem of cooperative competition. Any social species facing repeated interactions evolves some version of these mechanisms.