An internationally renowned scorpion expert and ecologist who shared his knowledge with scholars, students and television audiences is missing and believed dead after a boating accident in Mexico's Sea of Cortez. Gary Polis, 53, chaired and taught in UC Davis' environmental science and policy department. He had traveled to Mexico to lead a routine research expedition funded by the Earthwatch Institute, described by Earthwatch as an opportunity to learn about Baja Island predators, and as "heaven here on earth" for ecologists who study the diversity and abundance of species. Polis, along with an accompanying group of UC Davis students, Japanese visiting scholars, and Earthwatch study tour participants were studying the biogeography and ecology of lizards and spiders on the trip. Polis' research took him to the area at least two or three times annually, say his colleagues. Polis, a California native, was relatively new to the campus, having arrived in June 1998, after having taught at Vanderbilt University for more than 20 years. He grew up in Southern California, and earned his bachelor's degree at Loyola University of Los Angeles, and his master of arts and Ph.D. degrees at UC Riverside. Polis spent a sabbatical at UC Davis in 1992, found he and his family loved Davis, and then returned to live here 6 years later. Polis literally wrote the book on scorpions, including "Biology of Scorpions," (Stanford University Press), and in press, "Scorpions Biology and Research" (Oxford University Press), and co-authored a children's book, "Scorpion Man: Exploring the World of Scorpions" (Scribner and Sons), all written during the past decade. He also studied food webs and ecology of desert communities, about which he also published books, including co-authoring "Food Webs: Integration of Patterns and Dynamics," and authoring "The Ecology of Desert Communities" as well as numerous scientific, peer-reviewed papers. Polis has "been a leader in several fields in ecology, building on a superb background as a naturalist working in deserts, and more specifically, with scorpions," said Alan Hastings, a colleague in Polis' department. "His work on cannibalism basically established the importance of that interaction as a biological mechanism, rather than a curiosity." Polis chose to work on the islands of Baja because of special opportunities there, with a sea that is productive, land that is not, affording opportunities to look at processes that couldn't be found anywhere else in the world, Hastings said. "His work has been the foundation of much work in ecology over the past 20 years, his work on spiders, scorpions and the interactions between many different populations. " A 1991 Polis paper on food webs altered the research field of community ecology dramatically, Hastings said, and represented years of painstaking field work. In addition to being an outstanding scholar, Polis also was "pleasant and charming," says colleague Tom Schoener, a professor of evolution and ecology in the Division of Biological Sciences. Schoener also describes Polis as "intensely interactive. When I found I couldn't attend a talk of his at a symposium because of a time change, he gave me a private performance, illustrations and all, on the lawn outside the conference building." Polis' interest in sharing his scientific knowledge extended well beyond the academic world. Even before listing his publications on his resume, Polis lists his "contributions to the communication of science," which are numerous. Polis has appeared in National Geographic Explorer films, including one yet to be aired this year, PBS documentaries including "The Wild West" hosted by Alan Alda, and has been interviewed by the Los Angeles Times, National Wildlife Magazine, Smithsonian Magazine, Canadian Broadcast Corporation, the New York Times and CNN, among many other publications and broadcasts. Prior to beginning his university teaching career at Oregon State University, Polis taught high school science for a few years, and in 1972, was chosen as teacher of the year at El Camino High School, Los Angeles. His professional achievements include his recent election as president of the American Society of Naturalists, serving as an Aldo Leopold Leadership Fellow, and receiving, in 1992, a Fulbright fellowship for research. He held major grants from the National Science Foundation for his studies, which included numerous projects to examine El Nino effects on ecology, and from Earthwatch Institute, which funded the trip on which he was participating this week. Survivors include his wife, Sharon; son Evan, 10; and daughter Maia, 4; his parents Sam and Marie Polis, of Temecula; and four brothers and one sister, all in San Diego.