Natalija Kashuba: Mended by masticates: A study of archaeogenetic proxies of migration, settlement and health in North Eurasian Mesolithic

Abstract

A joint archaeogenetic perspective integrates diverse lines of evidence from archaeology and paleogenetics to advance our understanding of human prehistory. In this thesis I contribute to the corpus of archaeogenetic data by producing and analysing ancient genomic data from osseous and masticated material. 

Masticated birch bark pitch (also called resin) is presented as a novel source for ancient DNA that contains an abundance of data from different species. The masticated lumps analysed in this work, which come from a Mesolithic site in western Scandinavia, encapsulated human genetic information (individual genomes and oral microbiomes) and environmental aDNA from species (plants and animals) consumed or used as raw material at the site. Ancient DNA from this archaeological material transpires as a direct link between a practised archaeological culture and the genotype of the practitioners, in this case a particular lithic technology (the eastern pressure blade concept) and Scandinavian hunter-gatherers (SHG). The paleopathological information obtained from the microbiomes from this masticated material suggests poor oral health in the Early Mesolithic population of Scandinavia.

I use the genomic information obtained from various sources to examine hunter-gatherer populations in two opposite parts of northern Eurasia, the northeast Asia and the Scandinavian Peninsula. While the Mesolithic period in Europe has been subjected to intensive study, the paleogenetic history of northern Asia has remained only partially explored. I provide an overview of population dynamics in areas of northeast Asia and around Lake Baikal (Sakha republic, Cis-Baikal and Transbaikal) starting from the end of the Last Glacial Maximum (LGM). Additionally, the most northeastern occurrence of an early form of plague bacteria gets recorded, which is correlated with the population decline in the area during the Late Neolithic / Early Bronze Age periods. While this part of the world was occupied by humans through the LGM, the Scandinavian Peninsula was uninhabitable until the Holocene glacial retreat. By analysing new genomes from bones, teeth and masticated lumps, I also present a detailed study of demographic formation and change within the Mesolithic population in Scandinavia. Some of the demographic events presented in this thesis can be linked to changes in climate throughout the Holocene. 

I conclude that information obtained from both osseous and masticated material depicts a vivid picture of human life in distant areas of prehistoric northern Eurasia and provides new insights into paleodemography, mobility, settlement and health in the post-glacial world.