Religions are seen everywhere in the world. Two main theories are competing to explain this phenomenon. The first one is based on the assumption that our cognitive structures are predisposing us to nurture religious beliefs. Religion would then be a by-product of mental functions useful for survival. Examples of these mental functions are children credulity, anthropomorphism and teleology. The second one hypothesizes that religion is maintained trough direct adaptation benefits occurring in cooperation exchanges. In particular, religion could function as an insurance mechanism given by the religious group. It is likely that both theories are complementary and useful to explain why religion is a universal phenomenon in the human species.SCOP...