G. Ledyard Stebbins
George Ledyard Stebbins, Jr (6 January 1906 – 19 January 2000) was an American botanist and geneticist. He was one of the leading evolutionary biologists of the 20th century. Stebbins received his PhD in botany from Harvard University in 1931. He went on to the University of California, Berkeley, where his work led to a synthesis of plant evolution and genetics.