Dr. David W. Wolfe argues convincingly that life on our planet most likely began not in some primordial ocean but rather deep beneath the surface under extreme temperature conditions, and that this information should be considered in our search for extraterrestrial life. These largely unseen ecological communities play surprisingly critical roles in human civilization. Dr. Wolfe is Associate Professor of Plant Ecology in the Department of Horticulture at Cornell University, and a member of Cornell's Biogeochemistry Program.