Nearly every religious person I’ve spoken to believes that religion and evolution are compatible. However, I believe that this is because they do not fully understand the theory of evolution by natural selection. The Christian perspective, for example, believes either that 1) evolution did not actually happen, but just appears to have happened for surface plausibility or 2) that evolution did happen, and that God caused the big bang and therefore evolution by natural selection.
At this point in the argument I am expected by my religious friends to prove that god does not exist. However, evolution is not a proof that god does not exist. It is simply a scientific description of an optimization process. The way out of this argument at this point for a religious person is to say one of two things: 1) it just looks like we evolved 2) the big bang and/or the spark of life were “seeds” planted by god so that we might one day exist.
These two things are well and good, especially considering that we do not yet know how life started nor what caused the big bang. I consider it shortsighted to pin those two events on a god, but that is my own preference. You are free to believe its the case.
Then what leads me to believe these theories are incompatible? Once again it is that Christians, and presumably people of a variety of other religions, do not fully understand evolution. Evolution predicts that either religion evolved or that it is a natural byproduct of some other evolved brain functions. If you believe a priori that religion could not have evolved, you do not understand evolution! Furthermore, if you believe that it could not be a byproduct of evolution, you do not understand evolution.
In fact, I believe that we will find both of these things are true. Religion is a byproduct of evolution that turned out to be adaptive and was thus selected for. Let me be very clear about this: Genes that tend to make one teach what they have learned to their children, to try and make sense of the world, and to believe, often without merit, what other creatures believe, will proliferate in the gene pool. Furthermore, it is entirely possible that there are genes specifically for organized religion.
We do not yet have a theory of our own brain function, let alone the brain function of our Homo ancestors going back 2 million years. However, there are a few quite reasonable assumptions we can make based on current knowledge:
[ol]
[li]Having an identity (being able to relate certain facts to yourself) is adaptive[/li][li]Extending portions of your identity (e.g., empathy) to others in your group is adaptive[/li][li]The ability to be manipulated by others, and to manipulate others is adaptive[/li][li]Trying to make sense of your sensory data (the world) is adaptive[/li][/ol]
Points 1, 2 and 3 simply separate some members of Homo from our prior ancestors. They state that we are intrinsically social creatures, and that we have in fact evolved neural tissue dedicated to social processes. Point 4 follows from the optimization process that is evolution itself. The statistics of the world are reflected in many of our brain processes. We expect the world to make sense because, up until something evolved that could wonder what stars were, nearly everything in your environment that your survival depended on did make sense. Thus we have a tendency to assimilate data and choose an answer. However, whether or not that answer is correct does not immediately matter. It is simply not the case that we are instantly punished for thinking irrational thoughts. Creatures that think irrational thoughts have historically been selected against. At least that was true until a social evolutionary arms race began, where those whose power of cultural transmission was the most advanced (that is, the ability to be brainwashed by a large body of existing data upon birth) were the most likely to surive.
I fear that it will be very difficult for us to come up with incontrovertible proof for such a theory, or to even develop such a theory sufficiently far. Bones are preserved, brains are not. However, we do have our genome, and from our genome it may be possible to infer what the brains of our ancestors were like, and thus to contrast their cognitive processes with our own. At the very least, however, it seems plausible that our ancestors were in competition and those who were the most social, and dare I say the most religious, were the most adaptive. Religion provides continuity across generations. It brings people together. It allows people to manipulate eachother. It provides explanations for naturally curious brains! It has historically (and maybe even still today) increased the survival capability of individuals (and thus their genes) by linking them to the much more robust survivability of groups of individuals.
It seems clear to me that evolution can explain religion far better than religion can explain evolution. I further simply cannot understand why a religious person would want to claim they are compatible theories. Evolution clearly predicts that religious people are so because they have a robust ability to be brainwashed. The further implication is not that god does not exist, but that their belief in god is entirely unfounded.