Weak Altruism, Strong Group Selection

Throughout its history, the group selection controversy has been dominated by two major themes. The first involves the selection of groups in a metapopulation as a process analogous to the selection of individuals within single groups. The second involves altruistic behaviors that benefit others at the expense of the individual actor. Usually it is assumed that the two themes are fully compatible and that altruistic behaviors are the primary outcome of group selection. In this essay I point out some inconsistencies between the two themes. I also show that, by following the first theme to its natural conclusions, it is reasonable to expect strong group selection to operate in random associations, without any genetic relatedness among group members.