About the Author

Elisabeth S. Vrba is professor of geology and geophysics, adjunct professor of biology, and director of ECOSAVE CENTER at Yale University. George H. Denton is professor of geological sciences and Quaternary studies at the University of Maine. Timothy C. Partridge is senior research officer, Climatology Research Group; research associate, Paleoanthropology Research Unit; and honorary professor of physical geography at the University of Witwatersrand, Johannesburg. Lloyd H. Burckle is adjunct research scientist at the Lamont-Doherty Earth Observatory, Palisades, New York.