STEVEN D. GARBER, Ph.D., has taught biology at Cornell University, the City University of New York, and Rutgers University. He has worked as a biologist at the American Museum of Natural History, the National Park Service, Yale University's Peabody Museum of Natural History, and the New York City Parks Department. Garber is the author of The Urban Naturalist and the first edition of Biology: A Self-Teaching Guide (Wiley).