ABSTRACT
All the forms that globalization took over the course of the twentieth century, the biological changes—the alterations of the boundaries between living systems and the connections among them—were perhaps the most profound and far-reaching. Christopher Columbus did his part for biological globalization. Although the seeds he took with him to the New World on his first voyage did not survive the crossing, he had better luck on his second trip when he brought seeds of wheat, chickpea, melons, onions, radish, salad greens, grapevines, and sugarcane, as well as a collection of fruit stones to establish orchards. Agriculture in North America is simultaneously threatened by nonindigenous species and totally dependent on them. Every important food crop grown in the United States and Canada is a nonindigenous species. The biosphere, like all the species and populations and individual organisms that inhabit it, is in a continual process of change.
