The American geneticist Hermann Joseph Muller (1890-1967) was the first to induce mutations in an organism by severe x-ray treatment.

Hermann J. Muller was born in New York City on Dec. 21, 1890. His father died before Hermann was 10 years old, but he had already been imbued by his father with a sense of the grandeur of evolution and a sympathy for oppressed people. After graduation from Morris High School in the Bronx, he entered Columbia University. After receiving a master's degree there in 1911, he continued his studies at the Medical School of Cornell University for a year, returning to Columbia University for his doctorate, which he received in 1916.

At Columbia University Muller came under the influence of Thomas Hunt Morgan, who had gathered together a group of young researchers to study genetic inheritance in fruit flies (Drosophila melanogaster). Muller worked with this group in 1910 and discovered a fly mutant...