Neolithic Europe (7000 BCE-1700 BCE) Jan 16, 2020 18:52:34 GMT
Post by Admin on Jan 16, 2020 18:52:34 GMT
Principal component analysis of modern and ancient West Eurasians British and additional ancient samples are projected onto the reference space computed on present-day West Eurasian populations. See Methods for computational details and Supplementary Table 1 for information on the samples. PC, principal component. Site Abbreviations: Tisz. Doma., Tiszaszőlős-Domaháza; B.-au-Bac, Berry-au-Bac; C.-l.-Chau., Cuiry-les-Chaudardes; Falk., Falkensteiner Höhle; Vies. Hof, Viesenhauser Hof; Unterw., Unterwechsel; Halb.-Son., Halberstadt-Sonntagsfeld; Ber.-Moro., Berettyóújfalu-Morotva-liget; Polg.-Fer., Polgár-Ferenci-hát; Debr.-Tócó., Debrecen Tócópart Erdoalja; Komp.-Kig., Kompolt-Kigyósér; Apc-Berek., Apc-Berekalja I.; Salz.-Sch., Salzmuende-Schiebzig. Region: Brit-I, British Isles; C.-Eur., Central European; CH, Switzerland; ES, Spain; FR, France; GER, Germany; GR, Greece; HUN, Hungary; IRL, Ireland; IT, Italy; LU, Luxembourg; SW, Sweden; TR, Turkey. Plei., Pleistocene; H.-G., hunter-gatherer; Vil., Villabruna Cluster. Cultural Horizon: KÖR, Körös; EN, MN and LN, Early, Middle and Late Neolithic, respectively; M, Mesolithic; N, Neolithic; PWC, Pitted Ware Culture; LBK, Linearbandkeramik.
To investigate the proportions of Aegean farmer-related ancestry in the British samples we modelled them as mixtures of ANFs and European WHGs using the qpAdm method, which studies ensembles of f4 statistics (Figure 3, Supplementary Figure S8)24. The genomes of all British Mesolithic individuals can be explained almost entirely by WHG ancestry, the remainder (<7.3%) likely stemming from poorly matching portions of the genome. Most of the ancestry in all British Neolithic individuals could be attributed to ANFs (>56%, ~74% on average), indicating a substantial shift in ancestry with the transition to farming. To investigate the proximate source of ANF ancestry in British Neolithic individuals, we examined affinities with Early Neolithic individuals from Iberia and Central Europe. We compare Early over Middle Neolithic individuals as the latter are contemporary with the British Early Neolithic, making them an unlikely direct source. For all British Neolithic individuals considered we inferred more shared drift with Early Neolithic Iberians (Figure 4A, Supplementary Figure S9). However, these f4 statistic-based inferences may be sensitive to levels of WHG admixture, such that the similarity in WHG admixture proportions in Early Neolithic Iberian and British samples, but lower estimates in Central European Early Neolithic individuals, is driving the inference of an Iberian rather than Central European source for Early British farmers. To examine this possibility in more detail we performed a more powerful haplotype-based analysis.
WHG and ANF ancestry components of British and Central European Neolithic populations Relative WHG and ANF ancestry in Early and Middle Neolithic British and continental European populations quantified by qpAdm. Percentages indicate error estimates computed by block jack-knifing with a block size of 5 centimorgans (cM) (ref. ²⁴). See Methods for computational details and Supplementary Table 1 for lists of samples grouped into WHG and the different Neolithic populations. Neo., Neolithic; SouthE, South-East; SouthW, South-West.
Affinities of British and continental Neolithic populations Top, We computed f-statistics of the form f4 (Khomani, test; Central European EN, Iberia EN) for different British EN, MN and LN and continental MN populations to compare shared drift to Central European EN and Iberian EN populations. A positive Z-score > 2 corresponds to a significant affinity to the Iberian EN over Central European EN population. Bottom, Quantification of excess WHG ancestry in British EN compared to the Iberian EN population. We computed qpAdm estimates of WHG and Anatolian and Iberian ANF populations in EN samples from Wales, England and Scotland. See Supplementary Table 1 for lists of samples grouped into WHG and the different Neolithic populations. The three white bars and the coloured boxes indicate how the bars below them are derived. Percentages and bars indicate error estimates computed by block jack-knifing with a block size of 5 cM (ref. ²⁴).
Using a chromosome painting approach25 we obtained patterns of haplotype matching between our high coverage British Neolithic sample and a global modern reference panel (Supplementary Materials Section 7). We found similar patterns of donor haplotype matching in the British Neolithic genome to those inferred for other high coverage Neolithic genomes from Ireland and Iberia. These were more similar than the same profiles obtained for high coverage Neolithic genomes from Central Europe (Figure 5a). Inferred ancestry coefficients (see Materials and Methods) further support this connection between the British, Irish and Iberian Neolithic6 and are consistent with the same ancestral populations bringing the Neolithic to Britain and Ireland (Figure 5b,c, Supplementary Table S8). Additional modelling using global modern populations26 as ancestry surrogates suggests this population is best represented today by components found in French and Spanish peoples (Figure 5c, Supplementary Table S9).