Deserts cover about one third of the earth's surface and are the largest terrestrial ecosystem in the world. They are the only biome that is actually expanding, largely due to human activities and climate change. In the United States, six unique desert ecosystems stretch across the country: the Great Basin, Mojave, Chihuahuan, Sonoran, Peninsular, and the Painted Desert. Both a travelogue and science writing, North American Deserts:...