Wright, Sewall, 1889–1988, American geneticist, b. Melrose, Mass., B.S. Lombard College, 1911, M.S. Univ. of Illinois, 1912, D.Sc. Harvard, 1915. From 1915 to 1925 he worked in the Bureau of Animal Industry of the U.S. Dept. of Agriculture. He then taught (1926–54) at the Univ. of Chicago and was professor of genetics (1955–60) at the Univ. of Wisconsin. He conducted fundamental genetic studies, and is best known for his research on statistical patterns of heredity and evolution.

Wright, Sewall

(born Dec. 21, 1889, Melrose, Mass., U.S.—died March 3, 1988, Madison, Wis.) U.S. geneticist. He earned his doctorate at Harvard University. His earliest studies included investigation of the effects of inbreeding and crossbreeding on guinea pigs, animals he later used in studying the effects of gene action on coat and eye colour. With J.B.S. Haldane and R.A. Fisher, he developed a mathematical basis for modern evolutionary theory using statistical techniques. He originated a theory that could guide the use of inbreeding and crossbreeding in livestock improvement. He is perhaps best known for his concept of genetic drift.

Wright, Sewall (1889–1988) geneticist; born in Melrose, Mass. He worked in the Animal Husbandry Division of the U.S. Department of Agriculture (1915–25), where he began his fundamental studies of the frequently negative genetic effects of inbreeding in guinea pigs. He expanded his research to demonstrate the improvement of livestock populations by crossbreeding, offspring selection, and purposeful inbreeding. At the University of Chicago (1926–54), he did most of his theoretical work on mathematical theories of population genetics. He then moved to the University of Wisconsin (1955–60), where he remained active as an emeritus professor until his death from a fall during one of his habitual walks. He is known for his theory of genetic drift, which explained the role of small populations in evolution due to random fluctuations of gene frequencies. He integrated his own research with the work of Darwin and Mendel to establish a mathematical model for the genetic evolution of human and animal populations.