A genetic analysis has found the domestication history of maize to be more complex than previously thought, Reuters reports.
An international team of researchers sequenced the genomes of 40 indigenous maize landraces and nine archaeological maize samples from South America, and analyzed those samples in conjunction with published data on 68 modern and two ancient maize and teosinte genomes. Maize (Zea mays ssp. mays is thought to have evolved from wild Balsas teosinte (Z. mays ssp. parviglumis) in Mexico about 9,000 years ago.
As they report in Science, though, researchers led by the University of Warwick's Robin Allaby found that was only the first step. According to their analysis, maize was likely partially domesticated in the Balsas River region of Mexico and then dispersed to South America before domestication was complete. Those lineages were then domesticated in parallel.
"We found in the genomes evidence that South American maize actually originated within one of these semi-domestic lineages," first author Logan Kistler from the Smithsonian Institution's National Museum of Natural History tells Smithsonian.com. "You had these parallel evolutions happening in different parts of the Americas, with different groups of people."