In Sex At Dawn: The Prehistoric Origins of Modern Sexuality, co-authors Christopher Ryan and Cacilda Jetha take what they call the "standard narrative" of human sexual evolution and re-examine it through a different lens: suggesting that sexual exclusivity was not a part of our ancestor's expectations around relationships. Highlighting research in the fields of primatology, anthropology, evolutionary psychology and biology, Christopher Ryan tells Melody Thomas that monogamy is far from "natural" for our species, and that we'd have a much easier time with it if we went in informed.