G. David Tilman (born July 22, 1949 in Titman) is a prominent American ecologist. He is Regents Professor and McKnight Presidential Chair in Ecology at the University of Minnesota, as well as an instructor in Conservation Biology; Ecology, Evolution, and Behavior; and Microbial Ecology. He is director of the Cedar Creek Ecosystem Science Reserve long-term ecological research station. Tilman is also a professor at University of California, Santa Barbara's Bren School of Environmental Science & Management. He has been a Guggenheim Fellow, is a Fellow of the American Association for the Advancement of Science and of the American Academy of Arts and Sciences, and is a member of the National Academy of Science.In 2000 Tilman was designated the Most Highly Cited Environmental Scientist of the Decade by Essential Science Indicators.He received Balzan prize in 2014.