Nettie Stevens
American geneticist / From Wikipedia, the free encyclopedia
Nettie Maria Stevens (July 7, 1861 – May 4, 1912)[1] was an early American geneticist. She discovered sex chromosomes.
Nettie Stevens | |
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Born | Nettie Maria Stevens (1861-07-07)July 7, 1861 Cavendish, Vermont, United States |
Died | May 4, 1912(1912-05-04) (aged 50) Baltimore, Maryland, United States |
Cause of death | Breast cancer |
Education | Westford Academy |
Alma mater | Westfield Normal School Stanford University Bryn Mawr College |
Known for | XY sex-determination system |
Scientific career | |
Fields | Genetics |
Institutions | Bryn Mawr College, Carnegie Institution of Washington |
Thesis | Further studies on the ciliate Infusoria, Licnophora and Boveria (1903) |
Doctoral advisor | Thomas Hunt Morgan |
Doctoral students | Alice Middleton Boring |
Influences | Edmund Beecher Wilson Thomas Hunt Morgan |
Stevens saw two kinds of sperms in male mealworms. One had a large chromosome and one had a small chromosome. They were sex chromosomes, which later became known as the X and Y chromosomes.[2]
Stevens eventually became fully qualified. She received a PhD in cytology, with Thomas Hunt Morgan as her advisor. She died from cancer. She had worked at Bryn Mawr College, Naples Zoological Station and the University of Würtzburg during her short career.
One paper, written in 1905, won Stevens an award of $1,000 for the best scientific paper written by a woman.[3] Her major sex determination work was published by the Carnegie Institution of Washington in the two part monograph, Studies in Spermatogenesis.[4]