1861-1912

American Zoologist and Geneticist

Nettie Stevens provided evidence that sex is determined through the inheritance of specific chromosomes in germ cells, and she later discovered that chromosomes exist as pairs in cells of the body. Stevens worked with various types of insects, and in her studies of their germ cells she was able to illustrate two different systems of chromosomal inheritance that controlled the sex of offspring during reproduction.

Nettie Stevens worked as a school teacher from 1883-92 and a public librarian from 1893-95, when she returned to school at age 31 to earn a B.A. from Normal School in Westfield, Massachusetts. Stevens went on to complete both her B.A. in 1899 and her M.A. at Stanford University in 1900. After receiving her Ph.D. from Bryn Mawr College in 1903, she began working there as a research fellow in 1903, then became a reader...