Bioarchaeological and paleogenomic profiling of the unusual Neolithic burial from Grotta di Pietra Sant'Angelo (Calabria, Italy)

Abstract

The Neolithic burial of Grotta di Pietra Sant'Angelo (CS) represents a unique archaeological finding for the prehistory of Southern Italy. The unusual placement of the inhumation at a rather high altitude and far from inhabited areas, the lack of funerary equipment and the prone deposition of the body find limited similarities in coeval Italian sites. These elements have prompted wider questions on mortuary customs during the prehistory of Southern Italy. This atypical case requires an interdisciplinary approach aimed to build an integrated bioarchaeological profile of the individual. The paleopathological investigation of the skeletal remains revealed the presence of numerous markers that could be associated with craft activities, suggesting possible interpretations of the individual's lifestyle. CT analyses, carried out on the maxillary bones, showed the presence of a peculiar type of dental wear, but also a good density of the bone matrix. Biomolecular and micromorphological analyses of dental calculus highlight the presence of a rich Neolithic-like oral microbiome, the composition of which is consistent with the presence pathologies. Finally, paleogenomic data obtained from the individual were compared with ancient and modern Mediterranean populations, including unpublished high-resolution genome-wide data for 20 modern inhabitants of the nearby village of San Lorenzo Bellizzi, which provided interesting insights into the biodemographic landscape of the Neolithic in Southern Italy.

Figure 1

(a) Geographical location of San Lorenzo Bellizzi. Maps were obtained from the National Geologic Map Database project (https://ngmdb.usgs.gov/topoview/) and adjusted using Adobe Illustrator 2022 v3.0 (available at https://www.adobe.com/products/illustrator/); (b) Pietra Sant’Angelo massif and the entrance of the homonymous cave (black circle); (c) planimetry of the cave and location of the burial (red square); extent of the excavations is highlighted in green; (d) the skeletal remains of the individual as found inside the cave; (e) the intact jaws of the individual; photographs taken by Felice Larocca (b, d) and Alessandra Cinti (e).

Figure 2

(a) Mandibular portion of the jaws with visible extreme forms of wear patterns; (b) stereomicroscopic images of the occlusal surfaces of lower incisors and canines, with clear evidence of streaks (bottom and central) and fractures (top); (c) CT images of the jaws.

Figure 3

Principal Coordinates Analysis (PCoA) of the ancient oral microbiome content for SLB (red) and 114 samples from Neanderthal (green), pre-agricultural (orange), Neolithic (yellow), pre-antibiotic period (blue) and modern-day humans (light blue). Ellipses indicate the 95% confidence areas based on the standard error of the means of distances among samples of the same group.

Figure 4

(a) Phylogenetic reconstruction of ancient K-related mitochondrial lineages shows SLB falling into the variability of K1a + 195 haplogroup (olive green); (b) PCA projection of SLB individual into the variability of ancient Italian and Mediterranean Neolithics; (c) the distribution of G2a-related Y-chromosome lineages in ancient Europe between 8000 and 2500 BCE (left) and 2500 BCE—1500 CE (right). SLB is shown in a red square. Genomic data taken from the David Reich Lab Allen Ancient DNA Resources v54.1. Maps were obtained from the National Geologic Map Database project (https://ngmdb.usgs.gov/topoview/) and adjusted using Adobe Illustrator 2022 v3.0 (available at https://www.adobe.com/products/illustrator/); (d) when projected into the variability of modern Italians, SLB (blue dot) clusters in close proximity to the modern southern Italians (yellow dots) but does not overlap with them.