Theodosius Dobzhansky

Dobzhansky, Theodosius (1900–75), U.S. biologist, famed for his study of the fruit fly, Drosophila. His work demonstrated that a wide genetic range can exist even in a well-defined species and that the greater the “gentetic load” of unusual genes in a species, the better equipped it is to survive in changed circumstances.

See also: Biology; Fruit fly.