[2] Foster graduated from Dartmouth College in 1966 with a Bachelor of Science in biology, and attained his Botany / Plant Ecology PhD in 1974 at Duke University under ecologist Dwight Billings.
[1][3] In 1979, while at the University of Chicago, work on Barro Colorado Island with frequent coauthor Stephen P. Hubbell contributed to the development of the first tropical forest dynamics plot, leading to a global network of 18 such parcels.
[7] He has taught biology at the University of Chicago and served as a staff biologist at the Smithsonian Tropical Research Institute.
[3] At the Field Museum he founded the Live Photos of Plants project and Rapid Reference Collection.
[8][9] In 2013, Foster was elected an honorary fellow of the Association for Tropical Biology and Conservation (ATBC).