Our guest is Herman Pontzer, an Associate Professor of Evolutionary Anthropology at Duke University and Associate Research Professor of Global Health at the Duke Global Health Institute. An well-known researcher in human energetics and evolution, he joins us to discuss his new book, "Burn: New Research Blows the Lid Off How We Really Burn Calories, Lose Weight, and Stay Healthy." The book draws on Pontzer's groundbreaking studies with hunter-gatherer tribes in order to show how exercise actually