<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 goods went from the new world to the old world in the columbian exchange
maize potatoes tomatoes