Alfred Henry Sturtevant (November 21, 1891 – April 5, 1970) was an
American geneticist. Sturtevant constructed the first genetic map of a
chromosome in 1913. Throughout his career he worked on the organism
Drosophila melanogaster with
Thomas Hunt Morgan. By watching the development of flies in which the earliest cell division produced two different genomes, he measured the embryonic distance between organs in a unit which is called the
sturt in his honor. In 1967, Sturtevant received the
National Medal of Science.