[2][5] Her father worked as a carpenter and earned enough money to provide Nettie and her sister, Emma, with a strong education through high school.

After graduating in 1880, Stevens moved to Lebanon, New Hampshire to teach high school zoology, physiology, mathematics, English, and Latin.

[2] Seeking additional training in sciences, in 1896, Stevens enrolled in newly established Stanford University, where she received her B.A.

[2] She became increasingly focused on histology after completing one year of graduate work in physiology under Oliver Peebles Jenkins and his former student, and assistant professor, Frank Mace MacFarland.

[5][2] After studying physiology and histology at Stanford, Stevens enrolled in Bryn Mawr College to pursue her Ph.D. in cytology.

[2] In addition, Stevens' experiments were influenced by the work of the previous head of the biology department, Edmund Beecher Wilson, who had moved to Columbia University in 1891.

Stevens' post-doctoral year of work at the Carnegie Institution required fellowship support, and both Wilson and Morgan wrote recommendations on her behalf.

[8] During that fellowship year, Stevens again conducted research at the Naples Zoological Station and the University of Würzburg, in addition to visiting laboratories throughout Europe.

[2] Although Stevens did not have a university position, she made a career for herself by conducting research at leading marine stations and laboratories.

By experimenting on germ cells, Stevens interpreted her data to conclude that chromosomes have a role in sex determination during development.

Another researcher, Edmund Wilson made similar discoveries to her around the same time but hers were much larger leaps in the world of science and were the ideas which ended up being correct.

Morgan's recognition came in part from his work on sex linkage of the white mutant gene of fruit flies and was especially heightened by his Nobel Prize award in 1933.

[7] Morgan recognized Wilson's parallel but less complete and convincing studies [14] as producing a "joint discovery" with Stevens.

In an earlier letter of recommendation he wrote, "Of the graduate students that I have had during the last twelve years I have had no-one that was as capable and independent in research as Miss Stevens.

[11][19] Her single-mindedness and devotion, combined with keen powers of observation; her thoughtfulness and patience, united to a well-balanced judgment, account, in part, for her remarkable accomplishment.Modern cytological work involves an intricacy of detail, the significance of which can be appreciated by the specialist alone; but Miss Stevens had a share in a discovery of importance, and her work will be remembered for this, when the minutiae of detailed investigations that she carried out have become incorporated in the general body of the subject.In 1994, Stevens was inducted into the National Women's Hall of Fame.

[21] To celebrate her 155th birthday, on July 7, 2016, Google created a doodle showing Stevens peering through a microscope at XY chromosomes.