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 Great Basin. The book also explores the major attempts to explain the extinctions. Because some believe that they were due to the activities of human hunters, the author also reviews the archaeological evidence left by the earliest known human occupants of the Great Basin, showing that people were here at the same time and in the same places as many of the extinct animals. 

 
Were these animals abundant in the Great Basin? A detailed analysis of the distinctive assemblages of plants that now live in this region leads to a surprising, and perhaps controversial, conclusion about those abundances. 
 
If you are interested in Ice Age mammals or in the Ice Age archaeology of North America, if you are interested in the natural history of the Great Basin or the ways in which the plants of today’s landscapes might be used to understand the deeper past, you will be fascinated by this book.  

During the winter of 1846–1847, members of the Donner Party found themselves stuck in the snows of the Sierra Nevada on their journey to California, losing many in their group to severe cold and starvation. Those who survived did so by cannibalizing their dead comrades. Today the Donner Party may be the most famous of American overland emigrant groups, but it was not the only one to face extreme conditions. Ten years after the Donner Party, two groups sponsored by the Mormon Church, the Willie and Martin handcart companies ran into similar difficulties. Unlike the Donner Party, however, these people were following a well-traveled path, but they were doing it in a novel way—pushing and pulling their goods and children in handcarts some 1,300 miles from Iowa to Utah. Caught in early winter storms in Wyoming, 200 members of these two companies died along the trail.

The plights of these emigrant groups have been addressed by different historians in different ways; this book is the first to examine the tragedies in terms of biology. Grayson shows that who lived or died can largely be explained by age, sex, and family ties. His investigation reveals what happens when our cultural mechanisms for dealing with famine and extreme cold are reduced to only what our bodies can provide within structured social contexts. His results are surprising and not always intuitive as he investigates who survived in these life threatening situations.