Decoding Acheulean Percussive Technology: Experimental Approach to understanding Use-Wear Traces in different raw materials

Abstract The study of percussive technologies is crucial for understanding the cognitive and adaptive capacities of early hominins in all archaeological periods. Percussive technologies of early hominins testify to a large range of daily activities and serve as a source of information on raw material selection and tool-use strategies. These technologies also inform on the broader economic, social, and technical organisation of early hominin societies. While Acheulean assemblages document an increase in the variability of lithic raw materials and of types used for percussive tools compared to the Oldowan, the functional significance of such changes remains understudied. By experimentally assessing the effects of percussive actions on different raw materials, this study aims to advance our understanding and capability to identify use-wear traces related to bone percussion during the Acheulean, providing a reference that directly contributes to the study of the Melka Wakena site complex. In this paper, we present the results of a laboratory-controlled mechanical experiment combined with multi-scale analyses, including 3D scanning and multi-scale microscopy, to examine the effects of percussive actions on the natural surfaces of different raw materials. Our results show how the traces form in different raw materials, providing additional data to further characterization of traces. Such experimental data are fundamental for inferring decision-making criteria involved in the selection and use of various raw materials by early Acheulean stone toolmakers.