<P> The Columbian exchange, also known as the Columbian interchange, named for Christopher Columbus, was the widespread transfer of plants, animals, culture, human populations, technology, and ideas between the Americas, West Africa, and the Old World in the 15th and 16th centuries . It also relates to European colonization and trade following Christopher Columbus's 1492 voyage . Invasive species, including communicable diseases, were a byproduct of the Exchange . The changes in agriculture significantly altered and changed global populations . The most significant immediate impact of the Columbian exchange was the cultural exchanges and the transfer of people (both free and enslaved) between continents . </P> <P> The new contact between the global population circulated a wide variety of crops and livestock, which supported increases in population in both hemispheres, although diseases initially caused precipitous declines in the numbers of indigenous peoples of the Americas . Traders returned to Europe with maize, potatoes, and tomatoes, which became very important crops in Europe by the 18th century . </P>

What is the columbian exchange and what was exchanged
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