The biological and cultural transfer between the Old World and the New World that followed Columbus's 1492 voyage — connecting previously isolated ecologies through the movement of crops, animals, diseases, and peoples, producing one of the most catastrophic population collapses in human history and simultaneously reshaping the agricultural foundations of civilization on every inhabited continent
In 1492, Columbus connected two worlds that had been separated for approximately 15,000 years. What followed was not primarily a story about gold or conquest — it was a biological event of extraordinary magnitude. The diseases that European sailors carried — smallpox, measles, typhus, influenza — encountered populations with no immune experience of them and killed between 50 and 90 percent of the indigenous population of the Americas within a century. The other half of the Exchange was agricultural: maize, potatoes, tomatoes, cacao, and tobacco moved east; wheat, cattle, horses, and sugar moved west. The world's diet, and the world's demography, were permanently transformed.