It is difficult to think of a food more basic, more essential, and more universal than bread. Common to the diets of both the rich and the poor, bread is one of our oldest foods. Loaves and rolls have been found in ancient Egyptian tombs, and wheat has been found in pits where human settlements flourished 8,000 years ago. Many anthropologists argue that the ability to sow and reap cereals, the grains necessary for making bread, could be one of...