United States botanist. Raymond Carl Jackson, Emeritus Horn Professor of Biological Sciences at Texas Tech University, was born in Medora, Indiana, and attended the universities of Indiana (AB 1952; AM 1953) and Purdue (PhD 1955). Before joining Texas Tech University in 1971, he was a professor of botany at the University of Kansas. His research has dealt primarily with the biosystematics and cytogenetics of Machaeranthera (Asteraceae), Triticum (Poaceae) and various other genera of the Asteraceae such as Iva, Haplopappus and Helianthus. He is recognised for his work in cytogenetics, particularly on polyploidy, and for his discovery of low chromosome numbers in angiosperms. He is a member of the American Society of Plant Taxonomists, the International Organization for Plant Biosystematists, and the International Bureau of Plant Taxonomy and Nomenclature. In 2006 he was presented with the American Centennial Award from the Botanical Society of America. His Mexican collections began in 1957 and continued through the 1970s.