Geometric-morphometric analysis of tooth pits and the identification of felid and hyenid agency in bone modification

Abstract

Carnivore bone modification has been one of the targets of taphonomic research during the last decades. Discerning carnivore involvement in the archaeo-paleontological record during the Plio-Pleistocene is especially important due to the capability of several carnivores of creating bone assemblages, to the interaction with other species in the modification of bones across the landscape and to the potential interspecific competition (e.g., with other carnivores or hominins). Several variables have been explored to discern the carnivore taxa involved in bone modification, but most of them led to equifinality. Recently, the application of computer vision and geometric morphometric techniques for the reconstruction of tooth mark morphology has provided satisfactory results in terms of differentiating among carnivore taxa with similar body size. Here we apply this new technique to the study of pits from the Olduvai Carnivore site (OCS), which has been interpreted as the first bone assemblage generated by lions and subsequently ravaged by hyenas. Results support the lions' involvement and post-ravaging action of hyenas in the OCS assemblage. Lastly, we also explore the potential of applying these new techniques to other bone assemblages in which different carnivore taxa were involved in their modification.