Adjunct Curator, Vascular plants; Conservation Ecologist, Environmental & Conservation Programs

A.B., Biology, Dartmouth College, 1966.
Ph.D., Botany, Duke University, 1974.

Conservation biology/tropical forest ecology and geography/plant community composition and dynamics; floristics/reproductive biology of plants/environmental education.

Other positions
Senior Scientist Associate, Marie Selby Botanical Gardens, 1994-present.
Commission for Flora Neotropica, 1994-present.
Scientific Board, International Center for Tropical Ecology, 1991-present.
Investigador Asociado, Museo de Historia Natural, Lima, Peru, 1990-present.
Senior Ecologist, Conservation International, 1987-1994.
Research Associate, Missouri Botanical Garden, 1984-present.
Executive Committee, International Society for Tropical Ecology, 1976.
Trustee and Research Associate, Institute for Botanical Exploration, 1974-present.
Board of Directors, Organization for Tropical Studies, 1973-1980.
Assistant Professor of Biology, University of Chicago, 1972-1980.

Research
At a small scale, I am asking what determines tropical plant community composition, what makes species rare or common, and how and why things change over a long period. I have focused mainly on the Rio Manu in the upper Amazon of Peru, and Barro Colorado Island, Panama -- especially a 50-hectare plot on which my colleagues and I have mapped and measured a quarter-million woody plants and continue to monitor their growth and population changes. We are finding there is remarkable variation in species spatial-distribution. More important, in both sites the first few years of colonization and the role of animals are crucial in determining the local fate of the forest for the next several hundred years.

At the other extreme, I put the small-scale research in context by mapping the large-scale physiographic and floristic differences using diffuse sampling. The objectives are to interpret regional or continental-scale patterns of vegetation and floras and to select priority areas for conservation. This requires rapid sampling of huge areas and rapid identification of plants. The lack of tools and resources for identifying plants in the tropics is a bottle-neck for all researchers and students, and a barrier to public interest. It has provoked me to find new ways to do something about the problem, and to take advantage of the vast resource of tropical collections in the herbarium of The Field Museum.