The exchange of animal and plant populations across the Atlantic Ocean, known as the Columbian Exchange, began in the late 15th century and dramatically altered the ecosystems of both the Old and New Worlds. In a few centuries, the exchange established new crops and animals in new ranges.
Prior to the beginning of the Columbian Exchange in 1492, the New World had no horses, cattle, sheep, goats or pack animals, aside from llamas and alpacas. The Americas also had no wheat, rice or barley, which formed the staple crops of Old World civilizations. Corn, potatoes and manioc first became available to Europe as a result of the exchange.
Human populations also shifted dramatically. People of European and African origin became dominant across much of the Americas, while Native American people visited Europe for the first time. Each continent's cultures changed in response to the new influences from abroad.
Diseases also expanded their ranges with contact. Smallpox, bubonic plague and influenza crossed into North and South America for the first time with the early European settlers, explorers and conquerors, while syphilis first appeared among Europeans during this period. The new diseases dramatically altered the population profile of the Americas by initiating massive epidemics that wiped out millions of indigenous people.