George Ledyard Stebbins, Jr.  was an American botanist and geneticist who is widely regarded as one of the leading evolutionary biologists of the 20th century. George Ledyard Stebbins, Jr. was born January 6, 1906, in Lawrence, New York. Stebbins received his Ph.D. in botany from Harvard University in 1931. He went on to the University of California, Berkeley, where his work with E. B. Babcock on the genetic evolution of plant species, and his association with a group of evolutionary biologists known as the Bay Area Biosystematists, led him to develop a comprehensive synthesis of plant evolution incorporating genetics. Stebbins wrote numerous books, including Processes of Organic Evolution (1966), as well as some 250 journal articles. Among his later works are Flowering Plants: Evolution Above the Species Level (1974) and Evolution (1977). He received the National Medal Of Science in 1979.