Though several historians had published works on America's westward expansion prior, Paxson's Pulitzer Prize winning study was groundbreaking in its complete and unified presentation. Beginning with a survey of the frontier at the end of the French and Indian War and proceeding to follow the frontier westward until the close of the period of settlement in about 1890, Paxson's cross-sectional method carries the narrative in a wide windrow of detail, serving as a detailed and scholarly synthesis of the fragmentary work of previous historians.

Some 40 million miles of roadways encircle the earth, yet we tend to regard them only as infrastructure for human convenience. While roads are so ubiquitous they're practically invisible to us, wild animals experience them as entirely alien forces of death and disruption. In Crossings, environmental journalist Ben Goldfarb travels throughout the United States and around the world to investigate how roads have transformed our planet. A million animals are killed by cars each day in the US alone, but as the new science of road ecology shows, the harms of highways extend far beyond roadkill.

In What It's Like to Be a Bird, David Sibley answers the most frequently asked questions about the birds we see most often. This special brand-new audio edition is geared as much to nonbirders as it is to the out-and-out obsessed, covering more than 200 species. While its focus is on familiar backyard birds—blue jays, nuthatches, chickadees—it also examines certain species that can be fairly easily observed, such as the seashore-dwelling Atlantic puffin.

In 1908, near Folsom, New Mexico, a cowboy discovered the remains of a herd of extinct giant bison. By examining flint points embedded in the bones, archeologists later determined that a band of humans had killed and butchered the animals 12,450 years ago. This discovery vastly expanded America's known human history but also revealed the long-standing danger Homo sapiens presented to the continent's evolutionary richness. Distinguished scholar Dan Flores's ambitious history chronicles the epoch in which humans and animals have coexisted in the "wild new world" of North America.

The most enduring feature of US history is the presence of Native Americans, yet most histories focus on Europeans and their descendants. This long practice of ignoring Indigenous history is changing, however, with a new generation of scholars insists that any full American history address the struggle, survival, and resurgence of American Indian nations. Indigenous history is essential to understanding the evolution of modern America.