Great post.

JA, then where did humans get the brain circuitry that supports morals? Tooth Fairy?

I think we evolved general feelings of empathy as a side-effect of mating and child-raising, and the rest is comprised of cultural education. We don't have a moral sense, we have empathy and we have culture.

If we're talking survival of the fittest here, I can't see how adhering to moral codes could have outweighed the advantage (for men) of committing adultery, rape, stealing, and murder.