Fig. 6

Proposed dispersal of castor bean worldwide reconstructed from population genomics, and archeological records. Inset photographs show the domestication process from a woody tree originally distributed in East Africa (pale green) to an annual crop grown throughout the world. Accessions from East Africa are the extant wild progenitors of castor bean. Archeological evidence suggests prehistoric use of castor bean in South Africa and the early managements in Sudan and Egypt which subsequently spread to Europe. Western Asia (including Turkey, Syria, Iraq, and Iran; gray area) represents the center of genetic diversity of landraces and cultivars, from which cultivated castor bean likely spread to India and China. The movement of castor bean from Europe to America was a recent event