Columbus and his colleagues, I have suggested, did not discover a new world in America; they happened upon another old world. The discoverers did, however, consummate an abrupt, forced marriage between two hemispheres that after decades of gestation and a prolonged, difficult labor gave birth to something new. A wide variety of peoples hailing from three major landmasses – Eurasia, Africa, and America – melded to form cultures that were racially and culturally distinct from anything that had come before. Of this crucible was born Latin American civilization, a cultural hybrid. The Eurasian and African arrivals, however, carried more than cultural baggage; they also impregnated America's landscapes with new plants, animals, seeds, and germs, making of the Americas something of an ecological amalgam. The Old World's biological baggage, much of it stowaway, muscled in and grafted itself on to the lives and landscapes of America's existing ecological foundations. By the hundredth anniversary of this complicated union, the title “New World” finally made an apt description of both the cultural and natural consequences of the penetration of one hemisphere by another.