Much has been written about the “Columbian Exchange,” which refers to the plants and animals (and diseases) that were exchanged between the Old World and the New once Columbus started ships regularly traveling across the Atlantic. The Old World owes a lot to the New, especially in an agricultural sense. Potatoes, corn, tomatoes, cocoa, pineapples and pumpkins and a dozen other crops traveled from the New World to the Old so successfully that everyone’s diet changed radically. However,…