The disunity of cultural group selection

I argue that demographic selection, migration, and cultural diffusion, three mechanisms of institutional change, have little in common. Two of these lack the key features associated with group selection: they do not present us with group-level selection pressures counteracting individual-level ones, need not produce behavioral altruism, and do not require competition between groups whose members cooperate preferentially with one another. Cultural norms vary, change, and influence cooperation; but that is not group selection.