How in the world do you classify the more than one million species in the animal kingdom? This fact-packed book divides animals into the major phyla, including chordates, arthropods, and mollusks; the major classes, such as fish, amphibians, reptiles, birds, mammals, and insects; and by critical features, such as cell structure and the need to feed. Fascinating case histories examine the discovery of new mammal species, the need to conserve endangered...