The most popular theories for why humans have religion are: 1. To answer the existential mysteries--Why do we die? What is our purpose in life? Etc... 2. To increase social cohesion in tribes/groups My question is, at least for #2, there are 1000s of animals species that live in social groups and have perfectly adequate social cohesion mechanisms such as territoriality, dominance hierarchy, grooming, etc. Why would humans need religion to improve their social relationships when there are already abundant mechanisms and successful social species? For those of you who might be familiar with some of the theory of religion writers--Pascal Boyer, Dennett, Matt Rossano, and others--I haven't seen anybody ask this question. Is this a valid question? Is this a valid question for #1?