I have often wondered, and would like the thoughts of others on this, whether the predominance of religion in society is actually evidence of evolution in action. Not sure if I can get down my reasoning for this coherently but I'll have a bash.
What is it that makes the human race successful? The human race succeeds because of it's ability to live in large social groups; significantly larger than any other species on the planet. The ability to live in a large social group gives a number of benefits being protection, division of labour, sharing of resources, specialism of skills etc. However, humans are inherently selfish and ultimately the aim of most people (albeit that this is largely hidden under more complex emotional issues) is to ensure 1) their survival and 2) their happiness. So, for a race which is busy looking after no.1 the development of a large interactive, inter-dependent social structure seems unlikely. Here enters religion. Religion (amongst other devices) encourages individuals to set aside their immediate needs/wants/desires with the goal of a longer term guarantee of happiness (i.e. heaven) in the afterlife. So religion gives people a moral blueprint, which also happens to be a good way to live, if you live in a large social group.
The reason I think religion or a belief in religion is evidence of evolution in action is a comparitive issues. Imagine a time, say several thousand years ago, when you had two societies. One society functioned without religion, each person served their own personal need first, and the need of society second. The second society held religious views which allowed them to work more cohesively as a social group. Which society would succeed? The likelihood is that the society with religious belief would succeed and is more likely to thrive than the society without. In evolutionary terms survival of the fittest will out, therefore the society with religious belief would come to dominate and be prevalent - as it is in our society even if there are a number of religions and those religions do not necessarily agree. This would also be consistent with the regional nature of religion (which is, I accept, diminishing due to globalisation and the spread of an information culture) as people from the same global area generally have a coherent religious system, which in many ways will carry similarities to religious systems of their neighbours.
Not sure I've explained this overly well, and I'm certainly no expert on religion or evolution! However, I wonder whether there is any point asking people the question, 'Why do you believe in God'?, when this, in some respects, may be the same as asking 'Why do you speak English', if you were born in an English speaking country. Is religion evolution in action, or something more than that?
Is athiesm the next step in evolution?