A probing exploration of the mysteriously rapid disappearance of many amphibian species -- with disturbing portents for the wider ecological picture. Phillips is a pleasing science writer (Omni, Discover) who draws us into this warty topic with a touching boy-finds-frog story as told by an adult scientist she is working with. In 1960, the boy inadvertently killed his foothill yellow-legged frog by feeding it a pesticide-poisoned moth; ten years later no more of the frogs (Rana boylii) could be found in Southern California. This absence is far from a local ecological debacle: Scientists now realize that many species of one of Earth's oldest creatures are disappearing all over the globe. The little-known mystery that Phillips records got a public jolt when the celebrated Costa Rican golden tree-frogs (only discovered in 1967) vanished. Given glimpses of a scientist's field notes (""to view the golden toads breeding is like seeing the northern lights""), we begin to realize what natural grandeur has been lost. That grandeur is in the details of how frogs live, breed, and eat -- members of one species, now extinct, turned their stomachs into hatcheries and vomited out their young. This species offered new ways to treat ulcers, while the alkaloids extracted from some poisonous frogs can fight malaria, cancer, and pain. When not being trampled by hikers and bikers, frogs are being pickled by herpetologists and suffocated by pet and food shippers. The widespread declines, however, are linked here to more serious human crimes. Phillips takes us from scientific conferences to once pristine wetlands devastated by ultraviolet radiation (via the thinning ozone layer), greenhouse gases, acid rain, and other pollutants that combine with encroaching pasturage and construction to destroy amphibian habitats. ""Declining amphibians are like miner's canaries,"" writes Phillips, who shares her ""enchantment"" for the song of the pond and compels us to listen to its silence.