Betrayal in mateships, friendships, and coalitions

Over evolutionary history, different benefits have been gained and lost from long-term mateships, friendships, and coalitions. Humans have evolved psychological mechanisms that are sensitive to cues to possible diversion of benefits to people outside the relationship. Mateships friendships, and coalitions are predicted to share some of the same benefits but also to differ in some of the resources conferred. Accordingly psychological mechanisms sensitive to betrayal are predicted to operate in the same manner in those domains in which benefits are common across relationships and to operate differently in those domains in which benefits are unique to relationship type. Three interpersonal domains are investigated with regard to perceived betrayal: extrarelationship intimate involvement, intrarelationship reciprocity, and relationship commitment. Eight hypotheses are tested across the three relationship domains via perceived betrayal judgments. Results support a model of betrayal entailing some degree of domain specificity but also some generality across domains.