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How did selective breeding change corn and chickens?

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biology; microscope — Biology A researcher using a microscope to examine a specimen in the laboratory.

Selective breeding, or artificial selection, has profoundly transformed both corn and chickens to better suit human needs by altering their genetic makeup over generations.12

Corn (Maize)

Corn was domesticated approximately 10,000 years ago from a wild grass called teosinte. Early farmers selected plants with more kernels, gradually developing the crop into its modern form. In the 20th century, breeding techniques advanced significantly through the development of hybrid maize. By creating inbred lines and utilizing the "double cross" technique, scientists and farmers were able to combine desirable traits and exploit hybrid vigor, leading to dramatic increases in crop yields and the ability to tailor varieties to specific climates and soils.3245

Chickens

Chickens, primarily descended from the wild red jungle fowl, have been selectively bred for meat and egg production. Modern poultry breeding applies intensive mass selection and crossbreeding to achieve rapid weight gains and high egg output. These efforts have been highly successful: modern broiler chickens reach market weight in just five weeks—a fraction of the time required in the mid-20th century—and annual egg production per hen has tripled since 1910.67