Maize Domestication: The Where, the What, and the Huh?.

Maize was domesticated nearly 10,000 years ago from its wild ancestor, Zea mays ssp. parviglumis, and has undergone a radical phenotypic transformation resulting in an unbranched plant with seed attached to a cob, making it entirely dependent on humans for propagation.  In spite of substantial advances in the quantitative and population genetics of maize domestication, much remains unknown.  Here I present recent population genetic analyses that help resolve issues of the geography and genetic basis of maize domestication, as well as data that raises new questions.  First, using a wide sampling of landraces from across the Americas, I show that introgression from wild relatives can explain why maize from the highlands of central Mexico appears genetically ancestral.  Then I report findings from full-genome resequencing of maize and teosinte, showing that selection during domestication may have been stronger than during recent breeding.  Finally, I present recent data from teosinte populations that raise new questions about introgression and the genetics of maize domestication.