1890-1967

American Geneticist

Hermann Joseph Muller was a geneticist whose experiments with fruit flies demonstrated that x rays increase genetic mutations by altering gene structure. Upon discovering this connection, he began publicizing the danger of x rays and radiation, promoting radiation-safety measures, and fighting against nuclear bomb tests. His research on x rays was rewarded with the 1946 Nobel Prize for physiology or medicine.

Muller was born in New York City on December 21, 1890. He attended Morris High School in the Bronx, and then went on to Columbia University, where he received his bachelor's in 1910, his master's in 1911, and, after transferring briefly to Cornell University, his doctorate in 1916. During his years at Cornell, Muller was a member of Thomas Hunt Morgan's (1866-1945) research team. In 1910, the team verified that fruit flies had a fourth chromosome.

Before he earned his doctorate from Columbia, Muller became a biology...