TO GO WITH AFP STORY US-ENVIRONMENT-FOOD-CLIMATE-BOOK BY KARIN ZEITVOGELLester Brown, president of the Earth Policy Institute speaks during an interview with AFP at his office in Washington,DC on January 10, 2011. Like many environmentalists, Lester Brown is worried. In his new book 'World on the Edge,' released this week, Brown says mankind has pushed civilization to the brink of collapse by bleeding aquifers dry and overplowing land to feed an ever-growing population, while overloading the atmosphere with carbon dioxide. AFP PHOTO/Nicholas KAMM (Photo credit should read NICHOLAS KAMM/AFP/Getty Images)
