Sewall Wright; Geneticist Who Studied Evolving Species

Sewall Wright, 98, a geneticist known for his pioneering studies in evolving species. Wright, a professor emeritus at the University of Wisconsin-Madison, advocated a mathematical theory of evolution. One of his important theories was that chance happenings can have a significant effect on modifying the gene pool. Wright received 10 honorary degrees and was awarded the Darwin Medal, the National Medal of Science and, in 1984, the $100,000 Balzan Prize. “He was one of the great thinkers in all of genetics and evolution,” said James Crow, a University of Wisconsin colleague and longtime friend. “He was responsible--along with R. A. Fisher and J. S. B. Haldane--for our modern theory of evolution, selection and Mendelian inheritance.” In Madison on Thursday.