Stable carbon and nitrogen isotopes identify nuanced dietary changes from the Bronze and Iron Ages on the Great Hungarian Plain.

The Great Hungarian Plain (GHP) served as a geographic funnel for population mobility throughout prehistory. Genomic and isotopic research demonstrates non-linear genetic turnover and technological shifts between the Copper and Iron Ages of the GHP, which influenced the dietary strategies of numerous cultures that intermixed and overlapped through time. Given the complexities of these prehistoric cultural and demographic processes, this study aims to identify and elucidate diachronic and culture-specific dietary signatures. We report on stable carbon and nitrogen isotope ratios from 74 individuals from nineteen sites in the GHP dating to a ~ 3000-year time span between the Early Bronze and Early Iron Ages. The samples broadly indicate a terrestrial C3 diet with nuanced differences amongst populations and through time, suggesting exogenous influences that manifested in subsistence strategies. Slightly elevated δ15N values for Bronze Age samples imply higher reliance on protein than in the Iron Age. Interestingly, the Füzesabony have carbon values typical of C4 vegetation indicating millet consumption, or that of a grain with comparable δ13C ratios, which corroborates evidence from outside the GHP for its early cultivation during the Middle Bronze Age. Finally, our results also suggest locally diverse subsistence economies for GHP Scythians.

A minimally-invasive method for sampling human petrous bones from the cranial base for ancient DNA analysis.

Ancient DNA (aDNA) research involves invasive and destructive sampling procedures that are often incompatible with anthropological, anatomical, and bioarcheological analyses requiring intact skeletal remains. The osseous labyrinth inside the petrous bone has been shown to yield higher amounts of endogenous DNA than any other skeletal element; however, accessing this labyrinth in cases of a complete or reconstructed skull involves causing major structural damage to the cranial vault or base. Here, we describe a novel cranial base drilling method (CBDM) for accessing the osseous labyrinth from the cranial base that prevents damaging the surrounding cranial features, making it highly complementary to morphological analyses. We assessed this method by comparing the aDNA results from one petrous bone processed using our novel method to its pair, which was processed using established protocols for sampling disarticulated petrous bones. We show a decrease in endogenous DNA and molecular copy numbers when the drilling method is used; however, we also show that this method produces more endogenous DNA and higher copy numbers than any postcranial bone. Our results demonstrate that this minimally-invasive method reduces the loss of genetic data associated with the use of other skeletal elements and enables the combined craniometric and genetic study of individuals with archeological, cultural, and evolutionary value.