This is an interesting talk by Patricia Churchland on ethics, evolution, and the brain.
What was particularly interesting are the comments (from 28.10) on the way in which the evolutionary expansion of the forebrain in mammals and in humans allows greater prediction and anticipation of future events and social problems. That is no doubt a cause of the successful ability of humans to be social and live in groups.
While it is vitally important to understand what science has to say about the evolution of human moral ideas, just because we can identify some innate senses of right and wrong (which humans have evolved through social life in communities during our evolutionary history), it does not mean that we have found an objective theory of morality, one which that can function as a consistent, logical and universal system for justifying our moral choices, both now and in the past. This is in fact committing the appeal to nature fallacy.
The well-known fact that there is a vast chasm between what can be regarded as moral in one society and immoral in another demonstrates that, like our language faculty (which also has a biological basis), our innate moral intuition can lead to quite different systems of morality in different cultures in different times (just as our core language faculty leads to vastly different languages, with different words, grammar and syntax).
In the end, only an objective theory of morality (e.g., Kantian ethics, utilitarianism) can demonstrate that some things are immoral today and also immoral in the past or future. So it turns out the innate sense of right and wrong is not the same thing as an objective theory of morality.