Doughnuts at a Krispy Kreme store in Washington, D.C. An environmental coalition says leading doughnut companies like Krispy Kreme source palm oil from suppliers who are clear-cutting rain forests and destroying wildlife habitat. Meredith Rizzo/NPR hide caption

itoggle caption Meredith Rizzo/NPR

A truck carrying hardwood timber drives along a rural road leading to Paragominas, Brazil, on Sept. 23, 2011. The city has become a pioneering "Green City," a model of sustainability with a new economic approach that has seen illegal deforestation virtually halted. Andre Penner/AP hide caption

itoggle caption Andre Penner/AP

Should our growing understanding of pre-Columbian settlements in the Amazon have any bearing on the debate over the region's development today? Antonio Scorza/AFP/Getty Images hide caption

itoggle caption Antonio Scorza/AFP/Getty Images