Christopher Ryan is an author with a PHD in psychology. He wrote the best selling book, Sex at Dawn, a psychological and anthropological study on why monogamy just might not be natural to human beings. In this episode, he and Holly discuss the history of human sexuality and how it varies in cultures around the world. They also talk about the science behind why gangbang porn is so popular, and why some women have rape fantasies. If are interested in the psychology behind human sexual behavior, you do not want to miss this absolutely fascinating podcast!