It was through control of the shattering of wild seeds that humans first domesticated plants. Now control over those very plants threatens to shatter the world's food supply, as loss of genetic diversity sets the stage for widespread hunger.Large-scale agriculture has come to favor uniformity in food crops. More than 7,000 U.S. apple varieties once grew in American orchards; 6,000 of them are no longer available. Every broccoli variety offered through...