Final answer:
Commercially grown corn is a product of genetic modification through selective breeding from its ancestor, teosinte, which started around 9,000 years ago by indigenous people in Mexico. The small genetic differences significantly altered the plant's looks and utility, leading to the corn we know today.
Step-by-step explanation:
Commercially grown corn is likely genetically modified from its wild ancestor teosinte through selective breeding.
Teosinte is a wild grass from Mexico that is the ancestor of modern corn (maize). Selective breeding, a form of genetic modification, has been used over generations to transform teosinte into the highly productive corn plants we see today. This domestication process began approximately 9,000 years ago by indigenous people of what is now Mexico. The small genetic differences between teosinte and corn, specifically in developmental genes, have had a significant impact on the plant's morphology.
Early farmers selected for traits such as larger ears and easier access to seeds. Through this process, corn evolved from a wild grass with small, rigid fruit casings into the staple crop we rely on globally. Corn is now the most important staple in the world, not only for human and animal feed but also in industrial uses such as producing High Fructose Corn Syrup, plastics, and fuel.