Efficient cooperation often requires coordination, such that exactly one of two players takes an available action. If the decisions whether to pursue the action are made simultaneously, then neither or both may acquiesce leading to an inefficient outcome. However, inefficiency may be reduced if...

Despite the putative importance of ideological commitments in the evolution of large-scale cooperation among unrelated individuals, evolutionary researchers have yet to examine empirically the relationship between ideology and cooperation. We conduct an experimental game on Israeli kibbutz...