"If you look at us as a species, we're not very impressive. What we're good at is forming complex social networks," says Christopher Ryan, author of Sex at Dawn: The Prehistoric Origins of Modern Sexuality. "The purpose of human sexuality - the function - is social."
Watch Reason TV's interview with Ryan above. Or click below for downloadable versions and the full text and associated links.
Approximately 27 minutes.
Produced by Sharif Matar. Camera by Zach Weissmueller and Matar.
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