For millennia, lions, tigers, and their man-eating kin have kept our dark, scary forests dark and scary, and their predatory majesty has been the stuff of folklore. But by the year 2150 big predators may only exist on the other side of glass barriers and chain-link fences. Their gradual disappearance is changing the very nature of our existence. We no longer occupy an intermediate position on the food chain; instead we survey it invulnerably from above so far above that we are in danger of forgetting that we even belong to an ecosystem. Casting his expert eye over the rapidly diminishing areas of wilderness where predators still reign, the award-winning author of "The Song of the Dodo" examines the fate of lions in India's Gir forest, of saltwater crocodiles in northern Australia, of brown bears in the mountains of Romania, and of Siberian tigers in the Russian Far East. In the poignant and troublesome ferocity of these embattled creatures, we recognize something primeval deep within us, something in danger of vanishing forever.