Y1
Part of my Matildas series. The pattern is a portrait. I never say so on the wall, and people find the face on their own.
Nettie Stevens (1861-1912)
First to demonstrate that the Y chromosome determines sex (1905). Identified the XY system in beetles and flies. 38 papers in 11 years.
The Matilda Effect
Credit for her discovery went to Edmund Wilson, who published similar findings the same year but made a smaller theoretical leap.
Her doctoral advisor Thomas Hunt Morgan built his career on the chromosome theory she had proven, while he himself had resisted it. He won the 1933 Nobel in Medicine for that foundation. In her obituary, he called her a great technician, not a theoretician.
In 1906, Wilson and Morgan were invited to speak on sex determination at a major conference. Stevens was not.
Shown at Rouen National Arts 2026, Halle aux Toiles, next to Y².
