Knowledge held about animals by Pima-speaking Native Americans of Arizona and northwest Mexico is intimately entwined with their way of life—a way that is fading from memory as beavers and wolves vanish also from the Southwest. Ethnobiologist Amadeo Rea has conducted extensive fieldwork among the Northern Pimans and here shares what these people know about mammals and how mammals affect their lives. Rea describes the relationship of the River Pima, Tohono O'odham (Papago), Pima Bajo, and Mountain Pima to the furred creatures of their environment: how they are named and classified, hunted, prepared for consumption, and incorporated into myth. He also identifies associations between mammals and Piman notions of illness by establishing correlations between the geographical distribution of mammals and ideas regarding which animals do or do not cause staying sickness. This information reveals how historical and ecological factors can directly influence the belief systems of a people. At the heart of the book are detailed species accounts that relate Piman knowledge of the bats, rabbits, rodents, carnivores, and hoofed mammals in their world, encompassing creatures ranging from deer mouse to mule deer, cottontail to cougar. Rea has been careful to emphasize folk knowledge in these accounts by letting the Pimans tell their own stories about mammals, as related in transcribed conversations. This wide-reaching study encompasses an area from the Rio Yaqui to the Gila River and the Gulf of California to the Sierra Madre Occidental and incorporates knowledge that goes back three centuries. Folk Mammalogy of the Northern Pimans preserves that knowledge for scholars and Pimans alike and invites all interested readers to see natural history through another people's eyes.