DAVID L. PEARSON is a Research Professor in the Department of Biology at Arizona State University. His research is concentrated on ecological interactions among communities of species. He has studied habitats from desert grasslands and coral atolls to tropical rainforests and has written more than 75 scientific articles. Having conducted ecological research in Brazil, Peru and Ecuador intermittently during the past 30 years, he has become involved with environmental education and ecotourism in the region and is co-author of The New Key to Ecuador and the Galápagos, a tourist's guide to hotels, restaurants, and places of natural interest; of Ecuador and Its Galápagos Islands: The Ecotravellers' Wildlife Guide; and of Perú: The Ecotravellers' Wildlife Guide.