Retracing Nikolay Vavilov's Quest to End Famine

Is the world’s food supply stable? Will humanity be able to produce enough to feed itself in the future? The answers may lie in the research of a Stalin-era Soviet botanist. We’ll spend this hour with Gary Paul Nabhan, whose new book is “Where Our Food Comes From: Retracing Nikolay Vavilov’s Quest to End Famine” (Island Press, 2008).