Bridges, Calvin Blackman

Bridges, Calvin Blackman, 1889–1938, American geneticist, b. Schuyler Falls, N.Y., grad. Columbia (B.S., 1912; Ph.D., 1916). In his research he collaborated with T. H. Morgan, A. H. Sturtevant, and H. J. Muller, the group that developed many of the concepts of modern genetics through their study of the fruit fly, Drosophila. He continued with the Morgan group as a research associate of the Carnegie Institution in Washington from 1919. His contributions to modern genetics include the proof of the chromosome theory of heredity, formulation of the theory of genic balance, and the detailed study of giant salivary chromosomes in relation to the positions of genes. He was co-author of The Mechanism of Mendelian Heredity (1915).

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Bridges, Calvin Blackman

(born Jan. 11, 1889, Schuyler Falls, N.Y., U.S.—died Dec. 27, 1938, Los Angeles, Calif.) U.S. geneticist. He entered Columbia University in 1909 and assisted Thomas Hunt Morgan in designing experiments using Drosophila that showed that variations in the insect could be traced to observable changes in its genes. These experiments led to the construction of gene maps and proved the chromosome theory of heredity. In 1928 Bridges and Morgan moved to California Institute of Technology, where Bridges continued gene mapping and later discovered an important class of drosophila mutants caused by gene duplications.