Ferren MacIntyre, Journal of the American Academy of Religion, 2004, 72, 3, 653-694.
Abstract: The origin of reciprocal altruism remains puzzling. Kin selection fails because genes dilute quickly, and history does not support the differential success of more altruistic religions. Some features of religion can be related to kinship and were available to ancestral primates in whom any behavior that enlarged the apparent family by “pseudokinship” would spread. The evolutionary “function” of religion may be that (like racism) it is a form of pseudokinship that tricks the brain into thinking, “He looks like me, so we must be related,” and “She believes what I do, so she must be family,” with benefits to genes that permit this trickery. This may explain the universality of religious belief (and racism) and its survival independent of content and why belief must not be testable (an accessible belief is valueless for group definition). In a multiracial, multicredal world, racism and religion no longer usefully enlarge the community.