Peppers are indigenous to the Americas. They moved from the New World to the Old, and were quickly accepted all over the world, including China, Thailand, and India.
Corn, potatoes, tomatoes and pumpkins were also New World food products that were brought back to the Old World by early explores. Potatoes and tomatoes were both thought to be poison, and were slow to be accepted.
On this list wheat, grapes and rice were Old World products introduced into the New World, along with cattle, horses pigs, chickens, peas and various spices indigenous to India and Indonesia.
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