Roy was born on February 18, 1940, in Santa Monica, California, and grew up in Whittier, California. As a youngster, he spent many weekends tramping the Whittier hills looking for snakes and other interesting critters and frequently had unusual pets (most of the local amphibian and reptile species and an assortment of other critters including a screech owl, red-tailed hawk, crows, slow loris, coatimundi, etc.). Once he got a car and learned how to drive, he spent many weekends driving roads in the deserts of Southern California looking for snakes. In his sophomore year at the University of Southern California, he learned from one professor that with hard work and some luck one could make a living as a professional zoologist. He changed his major from premed to zoology, began concentrating on grades rather than social life, and was admitted to graduate school in 1961. He received an MS degree in 1966 for a thesis titled A study in biogeography: The herpetofauna of the Pacific lowlands of western Mexico and a PhD degree in 1968 for a dissertation titled Comparative morphology and evolution of the neotropical frog genera Atelopus, Dendrophryniscus, Melanophryniscus, Oreophrynella and Brachycephalus.
Roy has spent most of his career in museums and universities working on the systematics, behavior, ecology, and biogeography of amphibians and reptiles. His thesis work focused on the herpetofauna of dry forests in western Mexico, and he has spent considerable time in the field in Mexico, often working with colleagues from the Museo de Zoologia, Universidad Nacional Autonoma de Mexico. Roy was introduced to tropical wet forest habitats through classes with the Organization for Tropical Studies program in Costa Rica in 1966 and, since that time, he has done most of his field research in the Neotropics. He organized and taught several courses in the Tropical Studies program in the late 1960s and early 1970s. After a short time at the University of Chicago, he moved to Tampa and took a job at the University of South Florida. There Roy taught and directed graduate students from 1968 to 1978, primarily working with the ecology of Florida species of amphibians and reptiles. In Florida he served as state chairperson for a subcommittee of the Florida Committee on Rare and Endangered Plants and Animals and edited a volume on the Endangered and Threatened Amphibians and Reptiles of Florida. He first visited South America in 1976 to help establish a program in tropical ecology for the University of South Florida. He spent nearly six months in Ecuador after coming to Washington in 1978. Since arriving at the National Museum of Natural History, he has focused his research on understanding the diversity and natural history of amphibians and reptiles in lowland rainforests of Central and South America and has spent many months in Amazonian rainforest sites in Peru. He also co-organized a major expedition to the Cerro de la Neblina of southern Venezuela during 1983-85 and is an authority on the herpetofauna of the Guayana Highlands of that region.
During his career Roy has spent more than four years doing field work in 15 countries in the western hemisphere. He is the author and editor of more than 100 scientific publications and three books entitled: Measuring and Monitoring Biological Diversity - Standard Methods for Amphibians; Snake Species of the World - A Taxonomic and Geographic Reference, and Tadpoles - The Biology of Anuran Larvae.
Roy has served as a consulting reviewer for books published by the University of Oklahoma Press, Princeton University Press, and the University of Chicago Press. He was the science editor for the reptiles and amphibians section of Our Living Resources, 1995, and served as herpetological editor for the American Midland Naturalist from 1985 to 1991. He is a member of 24 scientific societies and was elected to the board or council of several. Roy was elected president of the American Society of Ichthyologists and Herpetologists, and also was president of the Herpetologists’ League and treasurer of the Society of Systematic Biologists. He has received many research grants and other honors during his career including recognition as distinguished teacher of the year at the College of Natural Sciences, University of South Florida; special achievement award, U.S. Fish and Wildlife Service; award for outstanding publication, U.S. Fish and Wildlife Service; and special achievement award, Patuxent Wildlife Research Center. He was elected fellow of the American Association for the Advancement of Sciences and member of the Societe Internationale pour l’Etude et le Protection des Amphibians, and the International Herpetological Committee, World Congress of Herpetology in 1989. In 1998, Roy and several other members of the Integrated Taxonomic Information System Partnership, with which he serves as chair of the Taxonomic Work Group, received Vice President Gore’s Hammer Award.
Roy was elected to membership in the Washington Biologists’ Field Club in 1986. He served as vice president from 2001 to 2005.
Roy is married to Grace A. Wyngaard, a biology professor at James Madison University and a past program director at the National Science Foundation. They live in Falls Church, Virginia, where Roy spends his non-work time gardening and chasing antiques.