Virtual Analysis of a Concretioned Skullcap From S'Omu e S'Orku, an Early Holocene Mesolithic Site of Sardinia

The study focuses on the analysis of the SOMK1 skullcap, a Mesolithic human remain from Sardinia encased in a thick concretion. The aim is to address the challenges presented by the concretion, which prevents direct examination, in order to explore the individual's biological and cultural relevance, duly contextualized within a broader population dynamic.

The SOMK1 skullcap was examined using a combination of chemical and digital techniques. The chemical analyses revealed that the red concretion encasing the skullcap was hematite-based and of cultural origin, thus preventing its removal. Computed tomography (CT) scans were used to virtually draw out and reconstruct the skullcap, enabling a detailed morphological analysis, as well as linear and geometric morphometric measurements. The analyses were contextualized by comparing SOMK1 against three samples, namely: island-dwelling hunter-gatherers dating to 800 CE, pre-Last Glacial Maximum (pre-LGM) European fossils, and Sardinian populations spanning from the Neolithic to modern times.

Digital analyses showed a dolichocephalic calvarium with morphometric traits consistent with a male individual. The cranial morphology matches pre-LGM European populations, differing from the brachycephalic forms observed in some Neolithic Sardinian populations. These findings suggest a possible link to earlier European populations, emphasizing the differences with later Sardinian groups.

This study shows how digital methods like CT scanning and virtual reconstruction effectively analyze human remains in concretion. The findings offer new insights into Mesolithic cranial morphology in the Mediterranean during the Early Holocene, enhancing our understanding of prehistoric Sardinia's population dynamics and cultural practices.