Are you those folks from across the sea? Biochemical analysis of human remains from the Roman Iron Age site in Grzybnica (Poland)

Abstract

Stone circles of the Wielbark culture, such as those found in Grzybnica, have long fascinated researchers, who debate their function and significance. The aim of the presented study is to determine the origins and subsistence strategies of the population buried near the stone circles in Grzybnica, which may help highlight the role of these sites within Wielbark communities. For analysis, human remains from the cemetery in Grzybnica, West Pomeranian Voivodeship, Poland, were utilized. Radiocarbon dating of five samples, stable isotope analysis of carbon and nitrogen in two samples, and strontium isotope analysis in 20 cremated human remains and 12 plant samples were conducted. Radiocarbon dating confirmed the earlier dating of the site to the period between approximately 80 and 260 CE. Dietary studies indicated that the individuals buried here regularly consumed millet (mean d ¹³ C = –17.8) and animal protein (mean d ¹5 N = 9.5). This diet corresponds with the variability described for the Wielbark culture site in Rogowo. The strontium isotope analysis revealed significant variation between the river valley (0.7157–0.7264) and the adjacent upland (0.7109–0.7138). The isotopic values in humans were homogeneous, ranging from 0.7113 to 0.7130, indicating no outliers that might suggest the presence of migrants. The variability observed in humans corresponds with the values observed on the upland. The results suggest that the group of individuals buried in Grzybnica was a small community that sourced their food from the upland. It is possible that this community was involved in the care of the stone circles, and the circles themselves may have been places of gatherings for local communities. However, it should be noted that only about 20 % of the graves found at the site were analyzed. The lack of migrants may be due to the low mobility of this group or methodological limitations related to the post-glacial nature of the geological substrate. Alternatively, it could also be due to the limitations associated with studying cremated remains, which allow for the reconstruction of events from only about 10 years prior.