Lithic Feature Identification in 3D based on Discrete Morse Theory

Abstract

Neanderthals and our human ancestors have coexisted for a large period of time sharing many things in common including the production of tools, which are among the few remaining artefacts providing a possible insight into the different paths of evolvement and extinction. These earliest tools were made of stone using different strategies to reduce a rather round stone to a sharp tool for slicing, scraping, piercing or chopping. The type of strategy is assumed to be correlated either with our ancestors or the Neanderthals. Recent research uses computational methods to analyse shapes of lithic artefacts using Geometric MorphoMetrics (GMM) as known in anthropology. As the main criteria for determining a production strategy are morphologic measures like shape, size, roughness of convex ridges and concave scars, we propose a new method based on discrete Morse theory for surface segmentation to enable GMM analysis in future work. We show the theoretical concepts for the proposed segmentation, which have been applied to a dataset being available via Open Access. For validation we have created a statistically significant subset of segmented simple and complex lithic tools, which have been manually segmented by an expert as ground truth. We finally show results of our experiments on this real dataset.