It was fish, not spices, that led to the discovery of North America," speculates anthropologist Fagan. From 1495 to 1525, he tells us, the monks at Westminster Abbey consumed almost 11,000 kilograms of fish per year. The sheer enormity of this piscine cuisine offers a snapshot of the exalted place fish held in the life of religious communities. Fagan (The Little Ice Age
) regales readers with a fast-paced, edge-of the-seat tale of Christianity's role in the development of fishing and fisheries as commercial ventures. By the fourth century, fish had become the center of Christian fast days and holy feasts. Early forms of aquaculture were developed to meet the demand, but eventually, as Fagan points out, Europe's rapidly growing Catholic population and its demand for fish on Fridays and fast days led, as early as the Middle Ages, to a North Atlantic fishing industry providing herring and cod and developing salting and smoking to preserve the fish for the transatlantic trip. But the onset of the Little Ice Age forced fishermen further south, and eventually they followed cod down to their winter waters off the coast of Maine. Fagan's rich prose creates a lively social history that will captivate readers of Mark Kurlansky and Jared Diamond. B&w illus. (Mar.)