Robert Harding Whittaker (1920–1980) was a distinguished American plant ecologist, active in the 1950s to the 1970s.
Born in Wichita, Kansas, he obtained a B.A. at Washburn Municipal College (now Washburn University) in Topeka, Kansas, and, following military service, his Ph.D. at the University of Illinois.
He held teaching and research positions at Washington State College in Hanford, Washington, the Hanford National Laboratories (where he pioneered use of radioactive tracers in ecosystem studies), Brooklyn College, University of California-Irvine, and, finally Cornell University.
Extremely productive, Whittaker was a leading proponent and developer of gradient analysis to address questions in plant community ecology. He provided strong empirical evidence against some ideas of vegetation development advocated by Frederic Clements. Whittaker was most active in the areas of plant community analysis, succession, and productivity. "During his lifetime Whittaker was a major innovator of methodologies of community analysis and a leader in marshaling field data to document patterns in the composition, productivity and diversity of land plant communities. Thus Whittaker was innovative in both empirical data sampling techniques as well as synthesizing more holistic theories.
He was the first to propose the five-kingdom taxonomic classification of the world's biota into the Animalia, Plantae, Fungi, Protista, and Monera. He also proposed the Whittaker Biome Classification, which categorized biome-types upon two abiotic factors: temperature and precipitation.
Whittaker was elected to the National Academy of Science in 1974, received the Ecological Society of America's Eminent Ecologist Award in 1980, and was otherwise widely recognized and honored. He collaborated with many other ecologists including George Woodwell (Dartmouth), W. A. Neiring, Herb Borman (Yale) and G. E. Likens (Cornell) , and was particularly active in cultivating international collaborations.
Ecologists completing Ph.D.s under Whittaker include Walter Westman, Robert Peet (now at University of North Carolina), Susan Bratton (now at Baylor University), Thomas Wentworth (now at North Carolina State University), Owen Sholes (now at Assumption College), Mark Wilson (now at Oregon State University), Linda Olsvig-Whittaker (now at the Israel Nature and Parks Authority) and Kerry Woods (now at Bennington College).
Whittaker married biochemist Clara Buehl (then a coworker at Hanford Laboratories) in 1952. Their children are John Whittaker (b. 1953, now a Professor of Anthropology at Grinnell College), Paul Whittaker (b. 1955, formerly an ecologist/entomologist; now an abstract artist and photographer in Evanston, Illinois) and Carl Whittaker (b. 1957, a natural history illustrator and professional chef in Ithaca, New York).
Clara was diagnosed with cancer in 1972; her health deteriorated and she died December 31, 1976. Whittaker married graduate student Linda Olsvig in 1979, but was himself diagnosed with lung cancer; he died October 20, 1980.