Adbriscoe · CC BY-SA 4.0

An evolutionary biologist who brought molecular tools into population genetics, using gel electrophoresis with J. L. Hubby in 1966 to reveal far more genetic variation within species than theory had predicted, work that reshaped how biologists think about evolution at the DNA level. With Stephen Jay Gould he coined "spandrel" to describe traits that are evolutionary byproducts rather than adaptations, and he spent much of his career arguing publicly against genetic determinism.