Why Be Generous? Tests of the Partner Choice and Threat Premium Models of Resource Division

Abstract

The ability to divide resources is crucial for a social and cooperative species like humans, but how humans divide resources remains unclear. Recent results using economic games have suggested conflicting models: The ‘partner choice’ perspective argues that generosity is (in part) a bid for an ongoing cooperative relationship, so generosity is expected to be elicited by cues of cooperative partner value. The ‘threat premium’ perspective argues that generosity is (in part) an attempt to avoid violent retaliation, so generosity is expected to be elicited by cues of threat potential. We tested these competing hypotheses using a dyad study in which pairs of undergraduate participants (N = 312) had a half-hour face-to-face conversation, evaluated each other on components of cooperative partner value and physical dominance, and completed 4 economic tasks comprising 7 resource division decisions. Generosity was uniquely predicted by cues of the ability to produce material benefits in an ancestral environment, this effect was stronger for men, and generosity tracked other measures of social attraction. In contrast, the partner’s physical dominance did not predict generosity. We observed support for the partner choice approach to resource divisions. Implications for the study of social preferences and resource divisions are discussed.