Genome Sequence of 5,310-Year-Old Maize Cob Provides Insights on Its Early Domestication

Researchers from the Natural History Museum of Denmark published a study of a 5,310-year-old maize cob from the Tehuacan Valley of Mexico, providing new insights into the early stages of maize domestication.

In the gene-by-gene analysis, the ancient sample shows many key genes had already been modified through human selection, including the lack of a hard seed coat and changes in flowering time. Archaeological evidence suggests that 5,000 years ago, people who planted and consumed maize likely lived in small groups of people from extended families, which explains why the ancient Tehuacan Valley maize is morphologically and genetically so distinct from modern corn.

Jazmín Ramos Madrigal, one of the authors of the study said that these ancient people moved seasonally and mostly consumed wild plants and animals, supplementing their diets with some domesticated plants. It was only during later periods with higher populations and socially stratified societies that maize became a staple. She cites the Olmecs (~1200 BC) and the Maya (200BC – 1000 AD), who required reliable and predictable food sources to support their cities, and it was at that point that maize would have undergone further selection for important traits.

For more details, visit the University of Copenhagen website.