European diseases almost exterminated the indigenous peoples of the Americas.

Today computer and communication technologies enable people all over the world to exchange information and goods and services, making the world seem a smaller place. What we call the Columbian Exchange, an equally important kind of exchange between the Americas and the rest of the world, began in 1492, when Columbus sailed from Spain across the Atlantic Ocean. With their arrival in the Americas, Columbus and the Europeans who came after him initiated contact between peoples and civilizations that had not been in contact for 9,000 years. Along with the exchange of people came a variety of other exchanges. We are still experiencing today both the positive and negative impacts of this contact. The exchange of crops across the Atlantic caused landscapes to change and populations to grow.

White potatoes, originally grown and domesticated in the Andes, today feed millions of people in northern Europe, Russia, and China. Wheat, on the other hand, was not grown in the Americas until it was brought there by Europeans. American corn, or maize, first domesticated by Native Americans, is now an essential crop in many nations, including Romania, Egypt, South Africa, and China. The tomato originated not in Italy but in the Americas.

Many animals were also introduced to the Americas by Columbus and other Europeans. Horses, cattle, goats, sheep, chickens, and house cats crossed the Atlantic Ocean with European travelers. North America, in exchange, gave Europe and Asia the turkey, gray squirrel, and muskrat. Of course, there were also negative consequences of the Columbian Exchange. The most devastating imports from Europe and elsewhere to the Americas were diseases: measles, typhus, plague, and smallpox. Native American populations had never experienced these diseases before and had no immunity to them. They were thus extremely vulnerable to such diseases, and millions died from them.