© 2015 Elsevier Inc. Seed-reliant, hunting and gathering economies persisted in arid Australia until the mid-twentieth century when Aboriginal foragers dropped seeds from their diets. Explanations posed to account for this "de-intensification" of seed use mix functional rationales (such as dietary breadth contraction as predicted by the prey choice model) with proximate causes (substitution with milled flour). Martu people of the Western Desert used small seeds until relatively recently (ca. 1990) with a subsequent shift to a less "intensive" foraging economy. Here we examine contemporary Martu foraging practices to evaluate different explanations for the dietary shift and find evidence that it resulted from a more subtle interaction of technology, travel, burning practices, and handling costs than captured solely by the prey choice model. These results have implications for understanding the roles of mobility, aggregation behavior, sexual division of labor, and seed use in the broad-spectrum revolutions of arid Australia and the Western United States.