George Wald

George Wald (November 18, 1906 – April 12, 1997) was an American biochemist renowned for elucidating the chemical basis of vision through his identification of vitamin A derivatives in retinal pigments.

Wald's research, beginning in the 1930s, demonstrated that rhodopsin—a protein in rod cells—undergoes photoisomerization upon absorbing light, triggering a conformational change from 11-cis-retinal to all-trans-retinal, which initiates visual signal transduction. This work, shared with Ragnar Granit and Haldan Keffer Hartline, earned the trio the 1967 Nobel Prize in Physiology or Medicine for foundational insights into photoreception mechanisms. As a Harvard professor from onward, Wald advanced understanding of cone cell pigments, linking distinct absorbances to color vision.

George Wald was born on November 18, 1906, in New York City to Jewish immigrant parents. His father, Isaac Wald, was a tailor who had emigrated from a village near Przemyśl in what was then Austrian Poland, and his mother, Ernestine Rosenmann originated from a small village near Munich in Bavaria, Germany. The family lived in a working-class neighborhood in Brooklyn, where Wald grew up amid modest circumstances tied to the garment industry.