As the Ice Age came to an end, North America lost a stunning variety of animals. Mammoths, mastodon, llamas, ground-dwelling sloths the size of elephants, beavers the size of bears, pronghorn antelope the size of poodles, and carnivores to chase them--sabertooth cats, dire wolves, American lions and cheetahs; these and many more were gone by 10,000 years ago. Giant Sloths and Sabertooth Cats surveys all these animals, with a particular focus on the...