on plants, animals, and humans. He uses a variety of archives to reconstruct past climate and environments including fossil pollen, plant macrofossils, tree rings, fossil insects, elemental geochemistry, stable isotopes, population genetics, and historical documents, artwork, and maps. Dr. MacDonald has published more than 120 peer-reviewed journal articles and numerous book chapters, reports, and other pieces, as well as an award-winning text on biogeography (Biogeography: Time, Space and Life, Wiley). He was elected a fellow of the American Association for the Advancement of Science and has won the McMaster University Award for Teaching Excellence and the UCLA Distinguished Teaching Award. Dr. MacDonald has served as the cochair of the National Science Foundation PARCS (Paleoenvironmental Arctic Sciences) program, chair of the Association of American Geographers Biogeography Specialty Group, and international coordinator (global change) for the International Boreal Forest Research Association, as well as associate editor or editorial board member for the Annals of the American Association of Geographers, Geography Compass, Journal of Biogeography, and Physical Geography. He received an A.B. degree in geography with highest honors and distinction from the University of California, Berkeley, an M.Sc. in geography from the University of Calgary, and a Ph.D. in botany from the University of Toronto.

Francis J. Magilligan is a professor in the Geography Department of Dartmouth College. His research interests focus primarily on fluvial geomorphology and surface water hydrology. In particular, his research addresses stream channel and watershed response to environmental change. He is a member of the Association of American Geographers (AAG), the Geological Society of America, and the American Geophysical Union. Dr. Magilligan has published more than 30 papers, and he has served as chair of the AAG Geomorphology Specialty Group and on the AAG Editorial Board. He received a B.A. in geography from Boston University, an M.S. in water resources management, an M.S. in geography, and a Ph.D. in geography from the University of Wisconsin at Madison.

William G. Moseley is associate professor of geography and director of the African Studies Program at Macalester College. He is a development and human-environment geographer with particular expertise in political ecology, tropical agriculture, environmental and development policy, livelihood security, and West Africa and southern Africa. Before becoming an academic, he worked for 10 years in the field of international development. His scholarly publications include 4 books, as well as more than 50 peer-reviewed journal articles and book chapters. He is also a committed public scholar who has published op-eds in such outlets as the International Herald Tribune, the Christian Science Monitor, the San Francisco Chronicle, and the Chronicle of Higher Education. He is chair of the national councilors of the Association of American Geographers (AAG), chair of the cultural and political ecology specialty group of the AAG, and editor of the African Geographical Review. His research has been funded by the National Science Foundation, the Fulbright-Hays Faculty Research Abroad Program, and the American Geographical Society McColl Family Fellowship.

Colin Polsky is an associate professor at the Clark University Graduate School of Geography. He is also director of the Human-Environment Regional Observatory (HERO) program, which provides opportunities for undergraduate and graduate students to analyze the causes and consequences of global environmental changes at local scales in faculty-led research projects, and research assistant professor at the George Perkins Marsh Institute. Dr. Polsky is a geographer specializing in the human dimensions of global environmental change, emphasizing the statistical analysis of vulnerability to climate change. He has explored ways to blend quantitative and qualitative methods for the study of social and ecological vulnerability to environmental changes in the Arctic (with a focus on traditional reindeer herding), the U.S. Great Plains (with a focus on contemporary agriculture), and central and eastern Massachusetts (with a focus on suburban water management). Dr. Polsky received his Ph.D. and M.S. (geography) degrees from the Pennsylvania State University, where he was a National Science Foundation Graduate Research Fellow, and B.S. (mathematics) and B.A. (humanities, French) degrees from the University of Texas at Austin. He has also completed a 2-year postdoctoral fellowship at Harvard University, with the Research and Assessment Systems for Sustainability program at the Belfer