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.