I suspect Robert Bellah's new book, Religion in Human Evolution, will be an important one for evolutionary explorations of religion - as outlined in this piece for the Guardian. A taster:

A fundamental mistake, Bellah argues, is to conceive of religion as primarily a matter of propositional beliefs. It is not just that this is empirically false. There are good evolutionary reasons for understanding religion in an entirely different way, too.

Go back deep into evolutionary time, long before hominids, Bellah invites his readers, because here can be found the basic capacity required for religion to emerge. It is mimesis or imitative action, when animals communicate their intentions, often sexual or aggressive, by standard behaviours. Often such signals seem to be genetically determined, though some animals, like mammals, are freer and more creative. It can then be called play, meant in a straightforward sense of "not work", work being activity that is necessary for survival.

This liberated play is found among creatures that don't have to work all the time, perhaps among offspring that are cared for by hard-working parents. It creates what the psychologist Gordon Burghardt has called a "relaxed field": the evolutionary changes that occur in this mode aren't driven by survival pressures.

Mimesis and play are so important in the story of religion because they are the precursors of ritual, that embodied way of being in the world that enacts, not thinks, understanding. If you have ever played peekaboo with a child, you were together learning about presence and absence. At a more sophisticated level, religions nurture the complex gestures of ritual and practice. Christians perform liturgies, Muslims prostrate themselves in prayer, Buddhists focus attention on breathing. This is the bread and butter of religion. Man can embody truth, reflected WB Yeats, when he cannot rationally know it...

On the back of ritual insight and symbolic representation comes theoretical exploration and theological propositions. But they are, in a way, epiphenomena to the more fundamental modes of religious understanding.

The ancient Greeks knew as much. When Plato deployed the word "theoria", he was referring to the ritual practice of making a journey to witness a life-changing spectacle or event, that were called "theoria". Hence, in his parable of the cave, the philosopher has to make an arduous journey towards the sunlight. He or she is more pilgrim than logician. But then Plato had the advantage of living before modern philosophers who sought to cleanse the discipline of living myth and metaphor, and align it with the literal truths of propositions.