The Great Lakes: The Natural History of a Changing Region

Five immense lakes lie at the heart of North America. They cover an area of nearly 95,000 square miles and hold more than 5,500 cubic miles of water. Together they comprise the world's largest freshwater system, containing 95 percent of the continent's fresh water - and one-fifth of the planet's total supply. Home to 40 million people, the Great Lakes' drainage basin is the hub of industry and agriculture in North America. More than a region; it is almost a nation in itself.

The Grea…