This is the story of 4,000 species; species that have outlived the dinosaurs and conquered the farthest places on Earth. And species that vary from the smallest, the two-inch pygmy shrew, to the largest, the blue whale; from the slowest, the sloth, to the swiftest, the cheetah; from the least attractive, the naked mole rat, to the most irresistible, a human baby. Some of the animals in this diverse group includ- The Insect Eaters- mammals, like armadillos, bats and anteaters, make meals of the most abundant creature on Earth. The Omnivores- many mammals are able to adapt their diets according to season, or have learned to hibernate through the winter when food is sparse. The Return to the Water- ocean mammals can take advantage of huge food stocks; how do seals, dolphins and whales breathe air yet swim to great depths? The Tree-Dwellers- creatures such as flying squirrels and colugos travel by gliding high among the tree-tops, but sloths hardly move at all. The Grasping Hands- only one group of mammals, the primates, have hands to grasp branches and pluck their food.