Artificial selection has produced modern corn (maize) from teosinte, a grass native to Mexico. Early farmers began to domesticate corn about 10,000 years ago by planting only the teosinte plants that produced the largest and tastiest seed heads. These plants would cross pollinate to produce the next generation of plants. Artificial selection of the best plants continued and eventually produced the modern corn varieties with their large ears of corn that we are familiar with today.
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