Richard Dawkins attempts to discover the reason why religion even started in his chapter “The Roots of Religion.” Dawkins goes through a number of theories, most of which he rejects. Not surprisingly, Dawkins leans more toward a Darwinist interpretation than a sociological interpretation. He suggests that humans evolved as children unquestioningly being obedient to parents and authority. This helped humans survive. Unfortunately (for Dawkins) it also developed into religion. I think scholars of religion (not just religious people) would be skeptical of this theory. Dawkins also focuses on the idea of a meme. Here is what Dawkins says:
“Some religious ideas, like some genes, might survive because of absolute merit. These memes would survive in any meme pool, regardless of the other memes that surround them. (I must repeat the vitally important point that ‘merit’ in this sense means only ‘ability to survive in the pool’. It carries no value judgement apart from that.)” (God Delusion, p. 231)
Or God could actually exist and our ancestors by instinct knew that we are not alone and that this life is not all there is. Remember, even in the animal world, instinct usually points to the truth.