Identification and quantification of projectile impact marks on bone:new experimental insights using osseous points

Abstract

Shifts in projectile technology potentially document human evolutionary milestones, such as adaptations for diferent envi- ronments and settlement dynamics. A relatively direct proxy for projectile technology is projectile impact marks (PIM) on archaeological bones. Increasing awareness and publication of experimental data sets have recently led to more identifca- tions of PIM in various contexts, but diagnosing PIM from other types of bone-surface modifcations, quantifying them, and inferring point size and material from the bone lesions need more substantiation. Here, we focus on PIM created by osse- ous projectiles, asking whether these could be efectively identifed and separated from lithic-tipped weapons. We further discuss the basic question raised by recent PIM research in zooarchaeology: why PIM evidence is so rare in archaeofaunal assemblages (compared to other human-induced marks), even when they are explicitly sought. We present the experimental results of shooting two ungulate carcasses with bone and antler points, replicating those used in the early Upper Paleolithic of western Eurasia. Half of our hits resulted in PIM, confrming that this modifcation may have been originally abundant. However, we found that the probability of a skeletal element to be modifed with PIM negatively correlates with its pres- ervation potential, and that much of the produced bone damage would not be identifable in a typical Paleolithic faunal assemblage. This quantifcation problem still leaves room for an insightful qualitative study of PIM. We complement previ- ous research in presenting several diagnostic marks that retain preservation potential and may be used to suggest osseous, rather than lithic, projectile technology