Are we born to run Christopher Mc Dougall

Christopher McDougall explores the mysteries of the human desire to run. How did running help early humans survive and what urges from our ancient ancestors spur us on today McDougall tells the story of the marathoner with a heart of gold, the unlikely ultrarunner, and the hidden tribe in Mexico that runs to live. (Filmed at TEDxPennQuarter. ) Talk by Christopher McDougall.