Over the past 50 years, global agriculture has transitioned almost entirely to an industrial model focusing on the cultivation of monocrops on huge tracts of farmland. One consequence of this practice is that biodiversity has decreased so much that now only 30 crops provide 95% of global food-energy and nutritional needs. In fact, since the 1960s, the U.S. has lost more than 90% of its varieties of fruits and...