For years, whenever someone asks me about the evolution of religion, I explain that there are two broad categories of explanation: that religion has conferred a selective advantage to people who possessed it, or that it was a byproduct of other cognitive processes that were advantageous. I’m a proponent of the byproduct explanation, myself; I tend to go a little further, too, and suggest that religion is a deleterious virus that is piggy-backing on some very useful elements of our minds.
Now look at this: there is a wonderful paper by Pyysläinen and Hauser, The origins of religion : evolved adaptation or by-product?, that summarizes that very same dichotomy (without my extension, however). Here’s the abstract:
Considerable debate has surrounded the question of the origins and evolution of religion. One proposal views religion as an adaptation for cooperation, whereas an alternative proposal views religion as a by-product of evolved, non-religious, cognitive functions. We critically evaluate each approach, explore the link between religion and morality in particular, and argue that recent empirical work in moral psychology provides stronger support for the by-product approach. Specifically, despite differences in religious background, individuals show no difference in the pattern of their moral judgments for unfamiliar moral scenarios. These findings suggest that religion evolved from pre-existing cognitive functions, but that it may then have been subject to selection, creating an adaptively designed system for solving the problem of cooperation.
The general argument for religion as an adaptive property is a kind of just-so story. Because humans are dependent on cooperation for survival, religion could have provided an internal bias to promote social cohesion, to promote feelings of guilt and fear about defecting from the group, and also to act as costly signals — you knew you could trust an individual to be a loyal member of your group if they were willing to invest so much effort in playing the weird religion game, just to get along. Strangers will not try to free-ride on your gang if membership involves snipping off the end of your penis, for instance. Also consider the chronic Christian condition of believing themselves to be an oppressed minority—that’s emphasized because if membership is perceived to be costly, even if it actually isn’t, it still can act as an inhibitor of free-riding.
The by-product model recognizes that there are advantages to cooperative group membership, but does not require the evolution of specifically religious properties; these are incidental features of more general cognitive capacities. In this case, we’d argue that such advantageous abilities as a theory of mind (the ability to perceive others as having thought processes like ours), empathy, and a need for social interaction are the actual products of selection, and that religion is simply a kind of spandrel that emerges from those useful abilities.
I favor the by-product theory because it is simpler — it requires fewer specific features be hardwired into the brain — and because it is readily apparent that many of us can discard all religious belief yet still function as cooperating members of a community, with no sense of loss. That suggests to me that religion is actually a superfluous hijacker of potentials we all share.
If you’re familiar with Hauser’s work, you know that he adds another datum: people moral judgments on the basis of a kind of emotional intuition. This intuition is independent of rationalizations and more complex institutional mandates, and is therefore far more deeply imbedded in our brains. We make choices based on feelings first, and the Ten Commandments are invoked later. Religion may work to reinforce some of those feelings, however, so it could act as a kind of cultural amplifier of more intrinsic biases.
To the extent that explicit religiosity cannot penetrate moral intuitions underlying the ability to cooperate, religion cannot be the ultimate source of intra-group cooperation. Cooperation is made possible by a suite of mental mechanisms that are not specific to religion. Moral judgments depend on these mechanisms and appear to operate independently of one’s religious background. However, although religion did not originally emerge as a biological adaptation, it can play a role in both facilitating and stabilizing cooperation within groups, and as such, could be the target of cultural selection. Religious groups seem to last longer than non-religious groups, for example.
In the future, more experimental research is needed to probe the actual relationship between folk moral intuitions and intuitive beliefs about afterlife, gods and ancestors. It seems that in many cultures religious concepts and beliefs have become the standard way of conceptualizing moral intuitions. Although, as we have discussed, this link is not a necessary one, many people have become so accustomed to using it, that criticism targeted at religion is experienced as a fundamental threat to our moral existence.
The idea that religion did not give us an evolutionary advantage, but has been shaped by cultural evolution to better fit and support our productive behaviors, is an interesting one. Of course, it doesn’t make religion right or good; what it suggests is that the strength of free-thinking communities could take advantage of some of the cognitive contrivances of religion, without the extraneous baggage of god-belief. We could just add a few costly signals to atheism, for instance.
So I’m going to have to ask you all to get genital piercings if you want to be a New Atheist.
(Don’t worry, just kidding!)