Nettie Stevens

Nettie Stevens
Born
Nettie Maria Stevens

(1861-07-07)July 7, 1861
Cavendish, Vermont, United States
DiedMay 4, 1912(1912-05-04) (aged 50)
Baltimore, Maryland, United States
EducationWestford Academy
Alma materWestfield Normal School
Stanford University (BA, MA)
Bryn Mawr College (PhD)
Known forXY sex-determination system
Scientific career
FieldsGenetics
InstitutionsBryn Mawr College, Carnegie Institution of Washington
ThesisFurther studies on the ciliate Infusoria, Licnophora and Boveria (1903)
Doctoral advisorThomas Hunt Morgan
Doctoral studentsAlice Middleton Boring

Nettie Maria Stevens (July 7, 1861 – May 4, 1912)[1] was an American geneticist who discovered sex chromosomes. In 1905, soon after the rediscovery of Mendel's paper on genetics in 1900, she observed that male mealworms produced two kinds of sperm, one with a large chromosome and one with a small chromosome. When the sperm with the large chromosome fertilized eggs, they produced female offspring, and when the sperm with the small chromosome fertilized eggs, they produced male offspring. The pair of sex chromosomes that she studied later became known as the X and Y chromosomes.[2][3][4]

  1. ^ "Nettie Stevens | American biologist and geneticist". Encyclopedia Britannica. Retrieved August 12, 2019.
  2. ^ Brush, Stephen G. (June 1978). "Nettie M. Stevens and the Discovery of Sex Determination by Chromosomes". Isis. 69 (2): 162–172. doi:10.1086/352001. JSTOR 230427. PMID 389882. S2CID 1919033.
  3. ^ "Nettie Maria Stevens – DNA from the Beginning". www.dnaftb.org. Retrieved July 7, 2016.
  4. ^ John L. Heilbron (ed.), The Oxford Companion to the History of Modern Science, Oxford University Press, 2003, "genetics".