More than 200 million years ago, geological forces split apart the continents. Isolated from each other, the two halves of the world developed totally different suites of plants and animals. Columbus's voyages brought them back together - and marked the beginning of an extraordinary exchange of flora and fauna between Eurasia and the Americas.
This global ecological tumult - the "Columbian Exchange" - was the greatest event in the history of life since the death of the dinosaurs. At the same time, it played an enormous role in human history, fostering the rise of Europe, devastating imperial China, convulsing Africa, and transforming the Americas. The Columbian Exchange began our era of globalization, and its effects continue today.