In a career that took him through Hitler's Germany and Stalin's Russia, Muller achieved scientific distinction while spawning political controversy. He is best known for his discovery that x-rays could induce artificial mutations in genes, a finding that won him a Nobel Prize in 1946.

Muller was born in New York City on December 1, 1890. His studies began at Columbia University, where he was influenced by Edmund Beecher Wilson and his emphasis on the role of chromosomes in heredity. Perhaps more importantly, Muller also became an associate of Thomas Hunt Morgan, researching natural mutations in Drosophilia (fruit fly). In Morgan's fly lab, Muller first established himself as an untraditional thinker, proposing imaginative theories and designing creative experiments. He may have been too much of an iconoclast, though, for his relationships with others were fractious, and Morgan himself found Muller somewhat presumptuous and idealistic. Personal conflicts aside, Muller's research at Columbia...