How does Evolutionary Theory inform ethics?
It does not. Evolution is the study of biology (life), whereas Ethics studies the moral values underlying a culture. Although evolutionary theory has been used to support Social Darwinism, there is no implicit ethical agenda inherent in the theory. It is worth noting that ethics and morality cannot simply be seen as being the products of religious belief either. This is laid out in an excellent and accessible book, What Ever Happened to Good and Evil? by UW-Madison philosophy professor, Russ Shafer-Landau.