Ten years ago, Northwestern University archaeologist Stuart Struever and his students--with the help of an alert amateur--discovered a cornfield on the Koster farm in west central Illinois strewn with promising artifacts. Here Struever recounts, artlessly but intriguingly, the growth of that site from a simple test dig with volunteer labor to a $500,000-a-year project that attracts 30,000 tourists annually. And with justification, for the Koster farm is one of the most important archaeological sites in North America, containing clearly separated layers of well-preserved remains that record more than 10,000 years of continuous occupation. The second part of the book, adding analysis to discovery, describes how pollen, seeds, fish scales, human skeletons, post holes, and other remains were studied to provide bits of new information. Each chapter is filled with little mysteries: Why did the residents eat hickory nuts and ignore equally available pecans? Why did the population suddenly expand after 5000 years of stability? More important still is the overall picture that emerges. By 6400 B.C., much earlier than previously thought, American Indians had stable, organized societies that exploited a wide range of food resources. By 5000 B.C., they had permanent dwellings and harvested wild seeds. Lack of evidence of warfare attests to their peaceful lives; the presence of mollusks from the Gulf of Mexico, of obsidian from Yellowstone, attests to continental trading networks. The text is sometimes repetitious, melodramatic, pedantic--but the book as a whole (there'll be many photos) puts a significant find within general reach.