Oswald J. Schmitz (left) is the Oastler Professor of Population and Community Ecology at the Yale School of Forestry & Environmental Studies, and is director of the Center for Biodiversity and Conservation Science. Thomas E. Graedel is the Clifton R. Musser Professor of Industrial Ecology at the Yale School of Forestry & Environmental Studies and is professor of geology and geophysics. He is also director of the Center for Industrial Ecology.