Matrilineal diversity and population history of Norwegians

Background While well known for its Viking past, Norway's population history and the influences that have shaped its genetic diversity are less well understood. This is particularly true with respect to its demography, migration patterns, and dialectal regions, despite there being curated historical records for the past several centuries. In this study, we undertook an analysis of mitochondrial DNA (mtDNA) diversity within the country to elaborate this history from a matrilineal genetic perspective. Methods We aggregated 1174 partial modern Norwegian mtDNA sequences from the published literature and subjected them to detailed statistical and phylogenetic analysis by dialectal regions and localities. We further contextualized the matrilineal ancestry of modern Norwegians with data from Mesolithic, Iron Age, and historic period populations. Results Modern Norwegian mtDNAs fell into eight West Eurasian (N, HV, JT, I, U, K, X, W), five East Eurasian (A, F, G, N11, Z), and one African (L2) haplogroups. Pairwise analysis of molecular variance (AMOVA) estimates for all Norwegians indicated they were differentiated from each other at 1.68% (p < 0.001). Norwegians within the same dialectal region also showed genetic similarities to each other, although differences between subpopulations within dialectal regions were also observed. In addition, certain mtDNA lineages in modern Norwegians were also found among prehistoric and historic period populations, suggesting some level of genetic continuity over hundreds to many thousands of years. Conclusions This analysis of mtDNA diversity provides a detailed picture of the genetic variation within Norway in light of its topography, settlement history, and historical migrations over the past several centuries.publishedVersio

Plant subsistence and environment at the Mesolithic site Tågerup, southern Sweden: new insights on the “Nut Age”

Pollen was analysed from a sediment sequence collected in the close vicinity of the Mesolithic settlement Tågerup, southern Sweden. Macroremains were also retrieved from numerous samples taken at the site of the archaeological excavations of Kongemose and Ertebølle settlement phases, 6700–6000 b.c. and 5500–4900 b.c. respectively. Plants and other organic remains were well preserved in the refuse layers from the settlements embedded in the gyttja. The pollen record includes no clear indications of human impact on the vegetation during the Mesolithic. The occurrence of charcoal particles and pollen of grass and herbs associated with nutrient-rich soils are contemporaneous with the Kongemose settlement. The Ertebølle settlement phase, although characterised by considerable dwelling activities less than a hundred metres from the pollen sampling site, is scarcely seen in the pollen data. Numerous finds of crushed dogwood stones from the Kongemose phase, often partly carbonised, suggest that these stones were used for the extraction of oil. Other plants found in the Kongemose refuse layers that may have been used are apples, cherries, raspberries, acorns and rowan-berries. Based on the abundance of hazelnut shells found at the studied site and in other studies of Mesolithic sites in southern Scandinavia it is proposed that these remains may testify to an important food supply rather than just use as a supplement to animal protein. It is also hypothesised that a regional decrease in hazel populations and thus hazelnut availability at the end of the Mesolithic may have motivated the adoption of Neolithic subsistence.</p