Today we understand that our world is infinitely richer than was ever previously guessed. Yet it is so ravaged by human activity that half its species could be gone by the end of the present century. These two contrasting truths - unexpected magnificence and underestimated peril - have become compellingly clear during the past two decades of research on biological diversity.

In this dazzlingly intelligent and ultimately hopeful book, Wilson describes what treasures of the natural world we are about to lose forever - in many cases animals, insects, and plants we have only just discovered, and whose potential to nourish us, protect us, and cure our illnesses is immeasurable - and what we can do to save them. In the process, he explores the ethical and religious bases of the conservation movement and deflates the myth that environmental policy is antithetical to economic growth by illustrating how new methods of conservation can ensure long-term economic well-being.