Brazil has the second-largest cattle herd in the world and is a major exporter of beef. While ranching in the Amazon--and its destructive environmental consequences--receives attention from both the media and scholars, the states of Mato Grosso and Mato Grosso do Sul actually host the most cattle. A significant beef producer in Brazil beginning in the late nineteenth century, the region served as a laboratory for raising cattle in the tropics, where temperate zone ranching practices do not work. Mato Grosso ranchers and cowboys transformed ranching's relationship with the environment,...