A Natural History of the Intermountain West was written to inform people about the wild world around us, with the idea that we all crave a connection to the natural world to ground us and give us a sense of place. It is also a book about change. While species are described throughout the chapters, the text is focused more on the profound processes that have shaped western ecosystems, based on a belief that understanding those processes is more meaningful than a list of names. The ways and the rapidity with which enormous ecosystems replace one another and sometimes even return as...