Corn

Modern corn does not have a simple wild range because it is a thoroughly domesticated crop. Its story begins in southern Mexico, where Indigenous communities started selecting useful traits from teosinte roughly 9,000 years ago. Genetic and archaeological evidence points especially to the Balsas River region as a center of early domestication.

Teosinte looks strikingly different from an ear of sweet corn. Its small seed cases hold relatively few kernels, while domesticated corn produces large cobs packed with exposed kernels. This transformation was not a single discovery but the cumulative work of farmers who repeatedly saved seed from plants with favorable qualities, including larger ears, softer kernels and harvestable cobs.

Corn spread through exchange, migration and continued local breeding across the Americas. Farmers adapted it to environments ranging from tropical lowlands to the Andes, the arid Southwest and eastern North America. Diverse flour, flint, dent, popcorn and sweet-corn types emerged, while techniques such as nixtamalization made dried corn more nutritious and easier to process.

After European contact, corn traveled rapidly to Europe, Africa and Asia. Today it is grown on an immense scale for food, livestock feed, starch, sweeteners, oil, ethanol and industrial products. The United States Corn Belt is now a leading production region, but corn’s biological and agricultural origins remain rooted in Mexico and in generations of Indigenous innovation.