Religion is a poor source of morality

[Neo-Scholastic]

But again that is all speculation on your part. I could also say that empathy is a reproductive disadvantage leaving compassionate people vulnerable to hostile groups. It is premature to say with any confidence that any particular evolved trait is primary for moral behavior and I believe there is good reason not to consider natural instinct a reliable moral guide. Virtuous action is often contrary to our natural instinct, like showing courage in the face of danger. You seemed to dismiss revulsion of deviate behavior as socially constructed problems. Could we not also say that social constructs like a sense of duty and honor contribute positively. Again socialization is neutral without reference to a higher standard of value that instinct or cultural norms.