The Ties that Bind Us

This paper reviews the evolutionary literature on cooperation and the mechanisms proposed to explain the differences we see in the scale, breadth, and intensity of cooperation across societies, over history, and among behavioural domains. The most well-studied mechanisms that help societies sustain cooperation include kinship, reciprocity, reputation, signalling, norms, informal and formal institutions, and the competition between stable equilibria sustained by these mechanisms. I apply each of these mechanisms to the problem of reciprocity across the lifecycle. I then discuss how these same ties also tear us apart and what policies might help tie us back together. JEL Codes: A12, A13, C71, J14, J18, Z1