As a quick review, yesterday I wrote about the naturalistic case for the origins of religion. This post is more of the nitty gritty of the theories concerning the evolution of religion. First, I think we should all be on the same page about what a theory actually is. How common is it that a Sky Fairyist talks about Evolution is just a theory! In everyday conversation (for us non-scientists at least) a theory is thought of as a guess. This guess may be good or bad (look at any tabloid and there are many theories running about). I found this definition of scientific theory from About.com:Chemistry
A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing. A theory is valid as long as there is no evidence to dispute it. Therefore, theories can be disproven. Basically, if evidence accumulates to support a hypothesis, then the hypothesis can become accepted as a good explanation of a phenomenon. One definition of a theory is to say it's an accepted hypothesis.I read The God Delusion, by Richard Dawkins, a while back and he has quite a bit dedicated on how religion may have developed. The following is taken from that book along with some other sources. When asking why a creature is the way it is you can phrase the question as, "Why is this adaptive? What does this behavior or body part, physiological process, etc do to keep this organism alive and pass on its genes?" Sex feels sooo good because it ensures that the act will be done repeatedly and ensures the next generation (d'uh). Why is religion adaptive?
When I went to school (a long time ago) we were taught about group selection. A particular trait is shared by a group of individuals and that characteristic allows that group to thrive. For example, a tribe of ancient people who had a kick-ass take no prisoner God would have a greater chance to thrive because they rolled over any competing tribes. I found an interesting article in the Mar. 4, 2007 New York Times Magazine titled Darwin's God (click here for entire article). Here is an discussion on how self sacrificing behavior is explained in terms of group selection. There are flocks of birds who have sentries to warn the rest of danger. Sentry birds, however, are more likely to be devoured since they're on the edge of the group and have less protection. How did this behavior develop?
To explain how a self-sacrificing gene can persist, Wilson looks to the level of the group. If there are 10 sentries in one group and none in the other, 3 or 4 of the sentries might be sacrificed. But the flock with sentries will probably outlast the flock that has no early-warning system, so the other 6 or 7 sentries will survive to pass on the genes. In other words, if the whole-group advantage outweighs the cost to any individual bird of being a sentry, then the sentry gene will prevail.Yes, the concept of group selection is controversial. I am not going into it here.
There is also the idea that religion is adaptive at the level of the individual. Richard Sosis, an anthropologist at the University of Connecticut and Hebrew University in Jerusalem, talks about the benefit for the individual who is religious (reminiscent of the chimp example that I gave yesterday).
Rituals are a way of signaling a sincere commitment to the religion’s core beliefs, thereby earning loyalty from others in the group. “By donning several layers of clothing and standing out in the midday sun,” Sosis wrote, “ultraorthodox Jewish men are signaling to others: ‘Hey! Look, I’m a haredi’ — or extremely pious — ‘Jew. If you are also a member of this group, you can trust me because why else would I be dressed like this?’ ” These “signaling” rituals can grant the individual a sense of belonging and grant the group some freedom from constant and costly monitoring to ensure that their members are loyal and committed. The rituals are harsh enough to weed out the infidels, and both the group and the individual believers benefit.However, not all scientists agree with the adaptive model for explaining religion. There is the religion as a by product theory that has been supported by Richard Dawkins. Dawkins (as well as others) propose that religion is a case of another thought process/instinct misfiring. There are examples of this behavior occurring in the animal world and I will use the example that is in The God Delusion of moths flying into flames. It so happens that when you get a moth it will fly in a circular motion into a candle's flame. Weird, eh? However, this behavior isn't some suicidal death wish of the moth. It has been shown that moths use the Moon and bright stars to navigate the night sky. Man made lights are new on the evolutionary scene and they mess up the moth's guidance system (because the beams of light from stars and the Moon are effectively parallel while the candle's light rays radiate out like spokes on a wheel) which cause the animal to fly into certain death. Religion, in this theory, is the outward behavior of another thought process not working appropriately, much like the moths' death spiral.
What is the underlying process that gives rise to religion? Dawkins proposes that the behavior that is misfiring is the child's belief in anything an adult authority figure will say to it. Human children rely on information from grownups (what is not safe to eat, don't go near the hippo (I have a hippo story, but this is not the time to tell it!),etc.) much more than other animals. The downside of this tendency is that the brain is susceptible to all kinds of falsehoods (belief in Sky Fairies, demons, and those virgins in heaven you get after blowing yourself up).
Oh, I could go on, and on, and on, but I won't. I think I bumbled through the question sufficiently to give a basic idea of the very tip of the iceberg on a very complicated and not fully understood topic.
Below is a lecture on the topic done by Daniel Dennett (here is his homepage). It is an hour and a half long, but I think you will get something out of it. I did.