The genomic ancestry of the Scandinavian Battle Axe Culture people and their relation to the broader Corded Ware horizon

 https://royalsocietypublishing.org/doi/10.1098/rspb.2019.1528

We generated and analysed genome sequence shotgun data from 11 individuals originating in northeastern Europe datedto 3300–1660 cal BCE (electronic supplementary material,table S1). Five individuals were excavated from CWC contexts:two from Obłaczkowo, Poland, one from Karlova, Estonia,and two from the CWC-related BAC burial Bergsgraven in Linköping, Sweden. The six additional individuals werefrom other archaeological contexts in Sweden: five from megalithic burial structures primarily associated with Funnel BeakerCulture (FBC) (two from Rössberga in Västergötland and threefrom Öllsjö in Scania) and one from a Pitted Ware Culture(PWC) context (Ajvide on Gotland). Radiocarbon dating showed that the three individuals from the Öllsjö megalithic tomb derived from later burials, where oll007 (2860–2500 calBCE) overlaps with the time interval of the BAC, and oll009and oll010 (1930–1650 cal BCE) fall within the Scandinavian Late Neolithic and Early Bronze Age (table 1; electronic supplementary material, table S1 and figure S2). Genome-wide sequence coverages range from 0.1 to 3.2×, and the sequence data for all individuals exhibit characteristic properties ofancient DNA: short fragment size and cytosine deamination at the ends of fragments (e.g. [24]) (table 1; electronic sup-plementary material, figure S5). Estimates of mitochondrialcontamination [25] were low, less than 2% for all 11 individuals, as was the estimated nuclear contamination on theX-chromosome in males [26,27] (less than 1.2%) (table 1; electronic supplementary material, table S3). Five individuals were genetically determined to be males, and six were females,based on the fraction of sequence fragments mapping to thedifferent sex chromosomes [28] (table 1)

The other individuals who were contemporary with BAC but had unclear cultural contexts, and who were buried in the Ölljsö megalith constructed many hundred years earlier (oll007), or found as a stray find (Ölsund) [9], show the same genetic profile as individuals from typical BAC contexts in other parts of Sweden

The best fitting two-source model was Funnelbeaker (FBC) + Yamnaya (YAM) (p = 0.86), while YAM + PWC (Pitted Ware Culture) would also fit the data (although trending toward low p-values; p = 0.07). These observations suggest that—to our statistical resolution—a direct PWC contribution to BAC is not needed in a model, but actual PWC admixture might have been small or there may have been indirect PWC contributions through PWC first mixing with FBC [34] who later contributed ancestry to BAC. Notably, using only the CWC population as the single source for BAC was consistent with the data in all cases (p > 0.05, except when using CWC-associated individuals from Latvia, CWC_LV).  The BAC groups fit as a sister group to the CWC-associated group from Estonia (CWC_EE, electronic supplementary material, figure S8) but not as a sister group to the CWC groups from Poland (CWC_PL, figure 3) or Lithuania (CWC_LT, electronic supplementary material) (|Z| > 3), indicating some differences in ancestry between these CWC groups and BAC. 

Funnelbeaker tombs were reused by the Battle Axe Culture.

The Scandinavian Middle Neolithic megalithic tombs are associated with the FBC. However, their reuse, indicated by artefacts common to the BAC and later periods, has been noted [17]. The oll007 individual, buried in the FBC-associated Öllsjö megalithic tomb, but radiocarbon dated to the time period of the BAC, is genetically very similar to individuals from BAC contexts (e.g. Bergsgraven and Viby). Thus, although archaeologically the reuse of megalithic tombs was assumed earlier [17], our study may be the first direct link (using genetics) showing that indeed FBC-associated megalithic tombs were used as burial places also for the people of the BAC. This could possibly also extend to the Danish Single Grave Culture (SGC) [49], as RISE61 [2], a male buried in the Kyndeløse passage grave and with a radiocarbon date overlapping with the BAC/CWC/SGC time period, also displays some steppe ancestry. 

 

Supplementary information: https://royalsocietypublishing.org/action/downloadSupplement?doi=10.1098%2Frspb.2019.1528&file=rspb20191528supp1.pdf

 

More here: https://onlinelibrary.wiley.com/doi/10.1002/ajpa.24079