It could also have an element of sexual selection involved. If it is desirable to find a mate who will act “ethically”, and humans are good at telling which humans are more “ethical” then others, then that would naturally strengthen the tendency to be ethical.
It could also have an element of sexual selection involved. If it is desirable to find a mate who will act “ethically”, and humans are good at telling which humans are more “ethical” then others, then that would naturally strengthen the tendency to be ethical.