The Kea, a crow-sized parrot that lives in the rugged mountains of New Zealand, is considerd by some a playful comic and by others a vicious killer. Its true character is a mystery that biologists have debated for more than a century. Judy Diamond and Alan Bond have written a comprehensive account of the kea's contradictory nature, and their conclusions cast new light on the origins of behavioral flexibility and the problem of species survival in human environments everywhere.