The question I asked you directly is whether we're free enough that it makes sense to talk about our moral responsibility for our actions. Instead of answering that question you changed the topic to that of social policy or strategy: we should behave as if we were free and should punish criminals, because that makes for the most successful society in evolutionary terms (it helps keep the birth rate up?).
You seem, then, to be unsure about whether we're actually free or not. So let me ask a related question: Do you think that if we're not really free, as in not autonomous or self-controlling, our talk of morality and of moral responsibility is pretty foolish? This is to say that even the secular philosophical talk of moral right and wrong would be as delusory as the religious excuses that are couched in myths?
The point I'm trying to get to is whether your evolutionary explanation entails or presupposes that morality in the intuitive or philosophical (as opposed to the reductive and possibly eliminative, game-theoretic) sense is bunk.
What determines whether a trait "pays off" in evolutionary terms is only whether that trait is in fact passed along because it contributes to the organism's fitness or at least doesn't impede the organism's ability to survive and procreate. Aggression, racism, and sexism have genetic bases which are very old. Therefore, those traits have already paid off.
You say rape is obsolete. Then why is rape so common in human societies? Why are most societies patriarchal and sexist? Why do we promote powerful men who are thus disposed to exploit women? Why do women exploit men's lust and degrade themselves for employment? All of this is perfectly natural, so on what strictly evolutionary grounds can you condemn it?
Perhaps because of the changing environment (the societies we're producing), those traits will die out in the future or are presently dying out. But the strategic logic of game theoretic puzzles seems to suggest only what should happen in evolution, not what actually does. The game theoretic logic must be ceteris paribus. If cooperation is a better strategy than defection and if natural selection simulates the results of game theory, then why isn't the wilderness a paradise? Obviously, there are other processes going on which game theory simplifies and idealizes for explanatory purposes.
Regardless, you're dodging the point. Natural selection is utterly amoral. There's all kinds of injustice, squalor, rape, torture, and murder in natural life perpetrated by the forces of evolution. All of that works in strictly evolutionary terms. You even said our species isn't so special compared to the other animal species. So on what basis do you condemn the obvious evils we commit, when you're tied to mere evolutionary reasoning?
I don't think you're understanding my point about the comparison with psychiatrists, but whatever.