Edgar Shannon Anderson (November 9, 1897 – June 18, 1969) was an American botanist. His 1949 book Introgressive Hybridization was an original and important contribution to botanical genetics.
Anderson was born in Forestville, New York, when he was three his family moved to East Lansing, Michigan where his father had accepted a position to teach dairy husbandry. In 1914 Anderson entered Michigan State College to study botany and horticulture. After completing his degree he joined the Naval Reserve and in 1919 he accepted a graduate position at the Bussey Institution of Harvard University. His studies were supervised by geneticist Edward Murray East and Anderson worked on the genetics of self-incompatibility in Nicotiana. He was awarded a master's degree in 1920 and a DSc in agricultural genetics in 1922.
He accepted a position as a geneticist at the Missouri Botanical Garden and was appointed assistant professor of botany at Washington University in St. Louis. His research was focused on developing techniques to quantify geographic variation in Iris versicolor. In 1929 he received a fellowship to undertake studies at the John Innes Horticultural Institute in Britain, where he worked with cytogeneticist C. D. Darlington, statistician R. A. Fisher, and geneticist J. B. S. Haldane. Anderson's data set on three related species of irises was used by Fisher as an example with which to demonstrate statistical methods of classification and has subsequently become very well known in the machine learning community, though often described as Fisher's iris data.