How do animals perceive the world, learn, remember, search for food or mates, communicate, and find their way around? Do any nonhuman animals count, imitate one another, use a language, or have a culture? What are the uses of cognition in nature and how might it have evolved? What is the current status of Darwin's claim that other species share the same "mental powers" as humans, but to different degrees? In this completely revised second edition...