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 seed catalogs in 1900 has now disappeared. As the international genetics supply industry absorbs seed companies—with nearly one thousand takeovers since 1970—this trend toward uniformity seems likely to continue; and as third world agriculture is brought in line with international business interests, the gene pools of humanity's most basic foods are threatened.The consequences are more than culinary. Without the genetic diversity from which farmers traditionally breed for resistance to diseases, crops are more susceptible to the spread of pestilence. Tragedies like the Irish Potato Famine may be thought of today as ancient history; yet the U.S. corn blight of 1970 shows that technologically based agribusiness is a breeding ground for disaster.Shattering reviews the development of genetic diversity over 10,000 years of human agriculture, then exposes its loss in our lifetime at the hands of political and economic forces. The possibility of crisis is real; this book shows that it may not be too late to avert it.