Fat content in leg bones of Bison bison, and applications to archaeology

Through chemical extraction, weight and percentage of fat are quantified for proximal, distal and medial sections of leg bones from three Plains bison. Bone grease weight is accurately predicted by dry bone weight (r(2)=0.981), bone volume (r(2)=0.959) and by density (r(2)=0.877). Binford's Grease Index is reviewed and found to be a questionable measure of bone fat. Results of this study and those of Emerson are generally complementary. Carnivore selection of bones correlates strongly with grease content (r=0.954). Differential yield of grease may help account for patterns of faunal abundance at certain bison kill sites. Bone grease is a minor but dependable and nutritious fat supply that may have been especially important during time of stress. As the last and the most destructive of butchering events, bone grease rendering has the potential to exert great influence over patterns of skeletal abundance. (C) 1997 Academic Press Limited.