Was maize domesticated in the Balsas Basin? Complex patterns of genetic divergence, gene flow and ancestral introgressions among Zea subspecies suggest an alternative scenario
The study of maize domestication has overlooked the genetic structure within maizes wild relative teosinte. Prior to investigating the domestication history of maize (Zea mays subspecies mays), one should first understand the population history of teosintes and how they relate to maize. To achieve this, we used 32,739 SNPs obtained from a broad sampling of teosinte populations and 46 maize landraces and a) inferred current and past gene flow among teosinte populations and maize, b) analyzed the degree of introgression among Zea mays subspecies, and c) explored the putative domestication location of maize. We found geographic structure and introgression between Zea mays taxa. Teosinte subspecies have diverged significantly from maize, which indicates that current teosinte populations have evolved mainly independently from maize since the domestication. Our results further suggest that the likely ancestor of maize may maybe have come from Jalisco or the Pacific coast.\n\nOne Sentence SummaryShared polymorphism in teosinte suggests a Jalisco origin of maize domestication.