People of the Dolmens and Stone Cists: An Archaeogenetic Investigation of Megalithic Graves from the Neolithic Period on Gotland

Description

The study of ancient genomics of pre-historic human remains has in recent years offered unprecedented knowledge regarding pre-historic migration and population structure on the European continent which has fundamentally altered the current views in the archaeological community. However, the merging of the two fields, archaeology and genetics, is still in its infancy and much work is still needed in order for these fields to integrate. In this thesis I explore how genetic analyses, in combination with contextual radiocarbon dating and isotopic analyses for diet and mobility can be used to investigate demographic events on a local and regional level. This is done through the investigation of people buried in five previously excavated megalithic tombs on the Island of Gotland dated to the Neolithic period. I present the genomic population structure and archaeological background for the pre-historic European reference data and show how this is used to investigate population continuity, demographic shifts, cultural duality, and admixture for local and regional contexts. I present new data and explore the Strontium-baseline for the Gotland biosphere which is used for the mobility analyses. I show that mitochondrial haplogroup data is especially useful in combination with isotopic data, and radiocarbon dating for investigation of demographic shifts on a larger scale. I also show that genomic data gives unique insights into the individuals’ life history which, together with the established demographic background allows for fine scale investigation of population demographic events within and between different archaeological contexts. Finally I show that the different Neolithic contexts on Gotland to a large extent involves immigration of new groups to the island, and that the contextual breaks seen in the archaeological record during the Neolithic period are connected with cultural and population demographic shifts. This dissertation demonstrates that genomic analyses, in combination with archaeology and isotopic analyses, as well as contextual osteological analyses and radiocarbon dating, present unique insights into the life history of the actual people who lived the lives we try to understand. Abstract List of Papers Contents 1 Introduction 2 Research aims and theoretical framework 2.1 Methodological concepts genetics/genomics 2.2 Methodological concepts diet and mobility 2.3 Current debates 2.4 Research aims 2.5 Theoretical framework 2.6 Theoretical methodology 2.7 Limitations 3 Archaeological background 3.1 The northern European Neolithic expansion 3.2 Mesolithic pottery in the Baltic Sea area 3.3 The Neolithization of Scandinavia and TRB 3.4 Middle Neolithic megalithic tombs 3.5 Distribution of PWC 3.6 Surrounded by Battle Axes 3.7 The Late Neolithic expansion and stone cist burials 4 Stone Age Europe seen through ancient genomics 4.1 Mesolithic Hunter-gatherer ancestry 4.2 Neolithization of Europe - genetic evidence 4.3 Pitted Ware Culture 4.4 Battle Axe Culture 5 Research background 5.1 The Late Mesolithic/ Early Neolithic transition 5.2 The Early/Middle Neolithic transition and the Ansarve dolmen 5.3 Middle Neolithic A (MN A, c. 3300-2800 cal BCE) 5.4 Middle Neolithic B (MN B, c. 2800-2400 cal BCE) 5.5 The Late Neolithic Stone cist burials 6 Material 6.1 The Ansarve dolmen (RAÄ Tofta 14:3) 6.2 The Häffinds stone cist (RAÄ Burs 9:1) 6.3 The Hägur stone cist (RAÄ: Eksta 72:1) 6.4 The Suderkvie stone cist (RAÄ: Grötlingbo 13:1) 6.5 The Utalskog stone cist (RAÄ: Alskog 48:1) 7 Methods 7.1 Sampling 7.2 The time aspect 7.3 Diet as a cultural definer 7.4 Mobility patterns 7.5 Genetic markers, inheritance patterns and variation 7.6 Ancient genomes from ancient people 7.7 Frequency patterns of mitochondrial haplogroups 7.8 Kinship analysis 7.9 Investigating population structure 7.10 Three-population and four-population tests 7.11 Population diversity 8 Synopses of the papers 9 Discussion 9.1 Chronology and population demographic developments seen through genetics 9.2 Dietary patterns over time 9.3 Strontium baseline 9.4 Mobility patterns 9.5 Kinship and internal relationships within the burials 9.6 Does genomics allow for fine scale analyses regarding the demo-graphic changes seen in the archaeological record on Gotland? 9.7 To what extent can the combination of the different scientific methods be used to provide new information regarding archaeological research questions concerning population continuity, migration and admixture in different time periods? 9.8 Reflections 9.9 Future prospects 10 Acknowledgements 11 References