Christopher Ryan is an American author best known for co-authoring the book Sex at Dawn. He received a BA in English and American literature in 1984 and an MA and Ph.D. in psychology from Saybrook University, an accredited hybrid low-residency/online learning program based in San Francisco, CA twenty years later. He spent the intervening decades traveling around the world working odd jobs. His masters thesis examined difference in specific personality measures between working fashion models and the general public. His doctoral dissertation analyzes the prehistoric roots of human sexuality, and was guided by the psychologist, Stanley Krippner, a humanistic psychologist, with additional committee members Sabrina Zirkel and J�rgen W. Kremer. Ryan gave a TED talk in February, 2013, contributes to Psychology Today and has an interview podcast called Tangentially Speaking with Dr. Christopher Ryan. He is married to his sometime collaborator and co-author of Sex at Dawn, Cacilda Jeth�.