Pedigree-based Bayesian modelling of radiocarbon dates

PLoS One. 2022 Jun 30;17(6):e0270374. doi: 10.1371/journal.pone.0270374. eCollection 2022.

Abstract

Within the last decade, archaeogenetic analysis has revolutionized archaeological research and enabled novel insights into mobility, relatedness and health of past societies. Now, it is possible to develop these results further and integrate archaeogenetic insights into biological relatedness with radiocarbon dates as means of chronologically sequenced information. In our article, we demonstrate the potential of combining relative chronological information with absolute radiocarbon dates by Bayesian interpretation in order to improve age determinations. Using artificial pedigrees with four sets of simulated radiocarbon dates we show that the combination of relationship information with radiocarbon dates improves the age determination in many cases at least between 20 to 50%. Calibrated age ranges are more constrained than simply calibrating radiocarbon ages independently from each other. Thereby, the precision of modelled ages depends on the precision of the single radiocarbon dates, the number of modelled generations, the shape of the calibration curve and the availability of samples that can be precisely fixed in time due to specific patterns in the calibration curve ("anchor points"). Ambiguous calibrated radiocarbon dates, which are caused by inversions of the calibration curve, can be partly or almost entirely resolved through Bayesian modelling based upon information from pedigrees. Finally, we discuss selected case studies of biological pedigrees achieved for Early Bronze Age Southern Germany by recent archaeogenetic analysis, whereby the sites and pedigrees differ with regard to the quality of information, which can be used for a Bayesian model of the radiocarbon dates. In accordance with the abstract models, radiocarbon dates can again be better constrained and are therefore more applicable for archaeological interpretation and chronological placement of the dated individuals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Archaeology* / methods
  • Bayes Theorem
  • Calibration
  • Germany
  • Humans
  • Radiometric Dating* / methods

Grants and funding

The research (including all scientific analyses) was mostly funded by the Heidelberg Academy of Sciences within the framework of the WIN project "Times of Upheaval: Changes of Society and Landscape at the Beginning of the Bronze Age". Furthermore, the research of Philipp W. Stockhammer and Alissa Mittnik was funded by the European Research Council (ERC) under the European Union's Horizon 2020 research innovation programme (ERC-2020-COG 101001951-MySocialBeIng) as part of Philipp W. Stockhammer's ERC Consolidator Grant project "MySocialBeIng: Mycenaean Social Belonging from an Integrative Bioarchaeological Perspective". The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.