Why do humans have butt cheeks? Neil deGrasse Tyson, Chuck Nice, and Gary O’Reilly learn about the biomechanics of running with professor and running specialist Dr. Irene Davis, featuring Neil’s interview with author Chris McDougall. NOTE: StarTalk+ Patrons can watch or listen to this entire episode commercial-free. Thanks to our Patrons Stephan Hoffmann Arvidsson, Louis Palen, Kara Young,Nick Skibicki, Jennifer Magnus, Ceasar Perez, Cameron Bishop,dniel, Pouneh Golabian, and Coleman for supporting us this week. Photo Credit: https://fshoq.com Subscribe to SiriusXM Podcasts+ to listen to new episodes of StarTalk Radio ad-free and a whole week early.Start a free trial now on Apple Podcasts or by visiting siriusxm.com/podcastsplus.