A well-reasoned, timely call for American agriculture to recognize that putting eggs in a single basket can lead to disaster. Raeburn, science editor for the Associated Press, adds to the growing literature on agricultural biodiversity with this book, rich in case studies on the depletion of the natural gene pool as industrial farming opts to cultivate ever fewer seed varieties. Warning that this leaves agriculture vulnerable to devastating crop diseases, Raeburn investigates the possibilities for renewal. He finds them in discoveries like that of Rafael Guzm†n of Mexico's University of Guadalajara, who turned up one of the last remaining strands of Zea diploperennis, a corn powerfully resistant to blight. Hybridized with commercially grown corn, Zea diploperennis can yield new kinds of corn--and, potentially, billions of dollars. Raeburn rightly asks, ``Have any other similarly valuable plants become extinct without ever having been seen by botanists?'' Raeburn offers stories of other successful ``gene hunters,'' like the heroic Nikolai I. Vavilov, whose scientific beliefs led to exile and death in the Gulag after he had collected thousands of rare seeds that helped revitalize Soviet agriculture in the famine of the 1930s. Closer to home, Raeburn extols Virginia farmer Elwood Fisher, who has preserved on half an acre an astonishing 840 varieties of apple, 160 pear, 52 cherry, 27 plum, 15 peach, 47 apricot, 20 grape, and 21 blueberry. Some readers may find Raeburn's alarmist outlook disconcerting; the corner Safeway seems, after all, to offer a bushel of choices. Yet he provides plenty of reasons to be concerned about the loss of ancient crops, rejoining, ``You can keep a winning streak going for a long time. But in the end, the house always wins.'' And if the house wins in this instance, Raeburn provocatively concludes, the result will be starvation.