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Post by Admin on Aug 18, 2021 20:05:56 GMT
The field of archaeogenetics has substantially contributed to a better understanding of how the movement and admixture of people across Europe during the Neolithic and Bronze Ages shaped genetic ancestries. However, not all regions are equally well represented in the archaeogenetic record. To fill this gap, researchers of the Max Planck Institutes for Evolutionary Anthropology (Leipzig) and the Science of Human History (Jena), University of Vienna and Croatian collaborators from Kaducej Ltd. and the Institute for Anthropological Research have now sequenced whole genomes of 28 individuals from two sites in present-day eastern Croatia and gained new insights into this region's genetic history and social structures. Present-day Croatia was an important crossroads for migrating peoples along the Danubian corridor and the Adriatic coast, linking east and west. "While this region is important for understanding population and cultural transitions in Europe, limited availability of human remains means that in-depth knowledge about the genetic ancestry and social complexity of prehistoric populations here remains sparse," says first author Suzanne Freilich, a researcher at the Max Planck Institute for the Science of Human History and the University of Vienna. To this aim, an international team of researchers set out to fill the gap. They studied two archaeological sites in eastern Croatia—one containing predominantly Middle Neolithic burials from within the settlement site, the other a Middle Bronze Age necropolis containing cremations and inhumations—and sequenced whole genomes of 28 individuals from these two sites. The researchers' goal was to understand both the genetic ancestry as well as social organization within each community—in particular, to study local residency patterns, kinship relations and to learn more about the varied burial rites observed. Middle Neolithic settlement at Popova zemlja Dated to around 4,700–4,300 BCE the Middle Neolithic settlement at Beli-Manastir Popova zemlja belongs to the Sopot culture. Many children, especially girls, were buried here, in particular along the walls of pit houses. "One question was whether individuals buried in the same buildings were biologically related to each other," says Suzanne Freilich. "We found that individuals with different burial rites did not differ in their genetic ancestry, which was similar to Early Neolithic people. We also found a high degree of haplotype diversity and, despite the size of the site, no very closely related individuals," Freilich adds. This suggests that this community was part of a large, mainly exogamous population where people marry outside their kin group. Interestingly, however, the researchers also identified a few cases of endogamous mating practices, including two individuals who would have been the children of first cousins or equivalent, something rarely found in the ancient DNA record. Middle Bronze Age necropolis at Jagodnjak-Krčevine The second site the researchers studied was the Middle Bronze Age necropolis of Jagodnjak-Krčevine that belongs to the Transdanubian Encrusted Pottery Culture and dates to around 1,800-1,600 BCE. "This site contains burials that are broadly contemporaneous with some individuals from the Dalmatian coast, and we wanted to find out whether individuals from these different ecoregions carried similar ancestry," says Stephan Schiffels. The researchers found that the people from Jagodnjak actually carried very distinct ancestry due to the presence of significantly more western European hunter-gatherer-related ancestry. This ancestry profile is present in a small number of other studied genomes from further north in the Carpathian Basin. These new genetic results support archaeological evidence that suggests a shared population history for these groups as well as the presence of trade and exchange networks. "We also found that all male individuals at the site had identical Y chromosome haplotypes," says Freilich. "We identified two male first degree relatives, second degree and more distantly related males, while the one woman in our sample was unrelated. This points to a patrilocal social organization where women leave their own home to join their husband's home." Contrary to the Middle Neolithic site at Popova zemlja, biological kinship was a factor for selection to be buried at this site. In addition the authors found evidence of rich infant graves that suggests they likely inherited their status or wealth from their families. Filling the gap in the archaeogenetic record This study helps to fill the gap in the archaeogenetic record for this region, characterizing the diverse genetic ancestries and social organizations that were present in Neolithic and Bronze Age eastern Croatia. It highlights the heterogeneous population histories of broadly contemporaneous coastal and inland Bronze Age groups, and connections with communities further north in the Carpathian Basin. Furthermore, it sheds light on the subject of Neolithic intramural burials—burials within a settlement—that has been debated among archaeologists and anthropologists for some time. The authors show that at the site of Popova zemlja, this burial rite was not associated with biological kinship, but more likely represented age and sex selection related to Neolithic community belief systems. So far, few archaeogenetic studies have focused on within-community patterns of genetic diversity and social organization. "While large-scale studies are invaluable in characterizing patterns of genetic diversity on a broader temporal and spatial scale, more regional and single-site studies, such as this one, are necessary to gain insights into community and social organization which vary regionally and even within a site," says Freilich. "By looking into the past with a narrower lens, archaeogenetics can shed more light on how communities and families were organized." Explore further Bronze Age migrations changed societal organization, genomic landscape in Italy More information: Reconstructing genetic histories and social organization in Neolithic and Bronze Age Croatia, Scientific Reports, DOI: 10.1038/s41598-021-94932-9
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Post by Admin on Aug 20, 2021 0:14:10 GMT
Reconstructing genetic histories and social organisation in Neolithic and Bronze Age Croatia Suzanne Freilich, Harald Ringbauer, Dženi Los, Mario Novak, Dinko Tresić Pavičić, Stephan Schiffels & Ron Pinhasi Scientific Reports volume 11, Article number: 16729 (2021)
Abstract Ancient DNA studies have revealed how human migrations from the Neolithic to the Bronze Age transformed the social and genetic structure of European societies. Present-day Croatia lies at the heart of ancient migration routes through Europe, yet our knowledge about social and genetic processes here remains sparse. To shed light on these questions, we report new whole-genome data for 28 individuals dated to between ~ 4700 BCE–400 CE from two sites in present-day eastern Croatia. In the Middle Neolithic we evidence first cousin mating practices and strong genetic continuity from the Early Neolithic. In the Middle Bronze Age community that we studied, we find multiple closely related males suggesting a patrilocal social organisation. We also find in that community an unexpected genetic ancestry profile distinct from individuals found at contemporaneous sites in the region, due to the addition of hunter-gatherer-related ancestry. These findings support archaeological evidence for contacts with communities further north in the Carpathian Basin. Finally, an individual dated to Roman times exhibits an ancestry profile that is broadly present in the region today, adding an important data point to the substantial shift in ancestry that occurred in the region between the Bronze Age and today.
Introduction Croatia in southeast Europe is home to a diverse landscape of contiguous ecoregions, with steep mountains separating the eastern Adriatic coast from the temperate Pannonian Plain in the north. Its central location at the interface of Central Europe, the Balkan Peninsula and the Mediterranean has long promoted it as a conduit to Anatolia, the Aegean and the steppe region as far as the Black Sea, with the northern lowlands connecting it to passes through the Carpathian Basin to Europe beyond1. Thus, this region was a significant corridor for the first migrating farmers from western Anatolia, who dispersed throughout the rest of Europe via inland and littoral routes along the Danube River and eastern Adriatic coast respectively2,3. While this region is important for understanding population and cultural transitions in Europe, limited availability of human remains means that in-depth knowledge about the genetic ancestry and social complexity of prehistoric populations here remains sparse.
Previous studies have demonstrated genetic discontinuity following the Mesolithic in west Eurasia, associated with the migration of early farmers and the spread of agriculture2,3. Published genome-wide data from a small number of ancient individuals from present-day Croatia have shown how Neolithic and Copper Age genomes share similar ancestry with early farmers from Anatolia, but some Copper Age and coastal Bronze Age individuals display additional ancestry associated with steppe pastoralist populations2 that dispersed into Europe during the third millennium BCE. The beginnings of social complexity in southeast Europe has also been an area of intensive study among archaeologists4. Increasingly, ancient DNA studies have explored intracommunity social organisation, revealing residency patterns, biological kinship and the social status of past societies5,6,7,8,9,10. For example, closely related individuals have been identified in Late Neolithic and Bronze Age communities from across Europe, often in association with high mitochondrial and low Y chromosomal diversity, indicating female exogamy and a patrilocal social organisation5,6,7. However, few in-depth, site-specific studies such as these have been conducted in this region to date.
The eastern region of present-day Croatia demarcates the southern edge of the Pannonian Plain (broadly synonymous with the Carpathian Basin), and is intersected by the Danube river, Sava, Drava and other large tributaries that are the site of many prehistoric settlements and formed an important part of communication and exchange networks in this area11,12. The emergence of the Neolithic here can be traced to the arrival of the Starčevo culture, which spread from present-day Serbia west and northwards into the Carpathian Basin13, while at coastal sites the Early Neolithic was marked by the presence of the Impressed Ware culture from about 6000 BCE14,15 (Fig. 1). By 5200 BCE the Starčevo had been superseded by the Sopot culture16,17, which practised intramural burial rites, where predominantly children and women were interred under the floors of houses and along walls or other locations within the settlement18,19,20. One important question ancient DNA can help to address is who was selected for such intramural burials, and whether biological kinship played a role. In addition, we can start to unravel whether genetic ancestry and biological kinship are linked to differences in mortuary rites such as body position, burial location within a site, or the distribution of grave goods, which can hint at the existence of different social groups, and could represent ascribed or achieved status of the deceased or the mourners19,21,22.
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Post by Admin on Aug 20, 2021 2:38:55 GMT
Figure 1 Location and dates of archaeological sites in Croatia. (a) Map showing location of archaeological sites for published and newly-reported samples (Table 1, Supplementary Tables S1 and S2). Each point represents a sample, with newly-reported samples outlined in black. Previously-published samples from Popova zemlja are outlined in orange. Genetic group labels include a shortened form of site or region: Pop Popova zemlja, Dal Dalmatia, Jag Jagodnjak. WHG indicates the group label Western Hunter-Gatherer. Shapes correspond to samples of different time periods: EN Early Neolithic, MN Middle Neolithic, BA Bronze Age, CA Copper Age, MBA Middle Bronze Age, RomanP Roman Period. See Methods for further time period labels used for other reference populations. Map made with Mapzen terrain tiles obtained from AWS Public Dataset (https://registry.opendata.aws/terrain-tiles/). European terrain data produced using Copernicus data and information funded by the European Union - EU-DEM layers. Ocean, river and lake data from Natural Earth. Free vector and raster map data @ naturalearthdata.com.Top left inset map of the region, made with map tiles by Stamen Design, under CC BY 3.0. Data by OpenStreetMap, under ODbL. (b) Combined radiocarbon and contextual date ranges for samples from present-day Croatia (Table 1, Supplementary Tables S1 and S2, Methods). Site names for newly-reported samples are highlighted in bold. All plots were produced using R 3.5.2102. By the Late Neolithic in southeast Europe and southern Transdanubia, a new mortuary practice emerged with the appearance of cemeteries located away from the space of the living18. This was accompanied by growing social distinctions among burials4,23, signalling an important change in people’s relationship with the dead18. The Croatian Copper Age (4500/4300 BCE—2400 BCE) saw the settlement of the Lasinja, Baden, Kostolac and Vučedol cultures, among others, in what is present-day continental Croatia24,25,26, which witnessed the growth of trade networks and more pronounced social hierarchy as seen in the appearance of high status burials27,28. The development of more marked social stratification appears to be linked with the growing use of metals in the Bronze Age, which spanned in present-day Croatia from about 2400—800 BCE, and saw a further increase in migrations from the eastern European steppes, the Aegean and Anatolia along with a rise in social ranking1,26. One of the numerous Middle Bronze Age cultures to co-exist in the Pannonian Plain was the Transdanubian Encrusted Pottery culture (Supplementary Text S2), which existed in a northern and southern form that extended into present-day eastern Croatia between 2000 and 1500 BCE12,29. To date, predominantly cremation burials have been found associated with this culture (Supplementary Text S2), however, now, with the new availability of inhumation burials, we can use ancient DNA to shed light on their genetic and social structure, and use the genetic data to learn more about social status as seen in the distribution of prestige grave goods. Here we present new genome-wide data for 28 individuals from two sites in present-day eastern Croatia, spanning from the Middle Neolithic to one individual dating to Roman times to investigate what impact the processes of migration and admixture had on genomic variation in this understudied region. Moreover, the presence of divergent mortuary rites at both an intramural burial site and an extramural cemetery from different time periods offers an opportunity to gain valuable insights into biological kinship, demography and social organisation in the context of the changing bio-cultural influences that shaped prehistory in the region.
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Post by Admin on Aug 20, 2021 20:29:57 GMT
Results Samples and archaeological background We screened a total of 54 individuals for whole genome shotgun sequencing (Table 1, Fig. 1a-b, Supplementary Table S1). Of these, we analysed 19 from the Middle Neolithic layer of Beli Manastir-Popova zemlja (abbreviated to Popova zemlja hereafter; Croatia_Pop_MN), which constitutes the largest Sopot culture habitation site to have been excavated in Croatia to date (Supplementary Text S1). Almost half of those excavated were under the age of 16, suggesting high subadult mortality. Two thirds of these were female, while males and females were represented equally among the adults. Most individuals were inhumed with Neolithic burial rites in contracted position along the walls of large pit houses or in other pits within the habitation site, sometimes with ceramic grave goods placed near their heads and other household items. Three of those sampled (POP07, POP09, POP14) (Table 1) were accompanied by a comparatively large number and variety of grave goods consisting of everyday items related to household and economic activities. Another four sampled individuals were deposited mostly in an extended prone or supine position in a channel running along the eastern edge of the site with few grave goods. New radiocarbon dates were also generated for one Copper Age individual (Croatia_Pop_CA) and one Roman period individual (Croatia_Pop_RomanP) from this site (Table 1, Fig. 1a-b, Supplementary Table S1). Approximately 12 km south lies the Middle Bronze Age biritual necropolis of Jagodnjak-Krčevine (abbreviated to Jagodnjak hereafter), attributed to the Transdanubian Encrusted Pottery culture (Supplementary Text S1, Supplementary Text S2). We analysed a further seven inhumations from this site (Croatia_Jag_MBA), which also contains over 30 cremations contextually attributed to the same period (Supplementary Text S1). Inhumations here contain varying degrees of grave good richness ranging from ceramic wares to gold personal ornaments. We co-analysed these new groups with published data from West Eurasian populations, in particular further Middle Neolithic individuals from present-day Croatia (Croatia_Osijek_MN), the Copper Age at Popova zemlja (Croatia_Pop_CA) and the wider region (Croatia_Radovanci_CA; Croatia_Vučedol_CA), and the Dalmatian Bronze Age (Croatia_Dal_BA), as well as groups across different time periods in present-day Hungary and the Balkan Peninsula2 (Fig. 1a,b, Supplementary Table S2).
Table 1 Summary information for ancient samples first reported in this paper. Capture data and calibrated radiocarbon dates for POP07 and POP14 were previously reported in2. See Methods and Supplementary Table S1 for further information about data provided in the table.
Individual ID Site name, archaeological time period and culture Date range (BCE contextual; calBCE/calCE 95.4% CI calibrated radiocarbon age) Population analysis label Genetic sex # autosomal SNPs overlapping with 1240 K panel mtDNA haplotype Y haplotype POP02 Beli Manastir-Popova zemlja Middle Neolithic Sopot 4700–4300 BCE Croatia_Pop_MN F 855,968 K1a POP04 M 884,196 H J POP05 F 790,411 K1a5 POP06 F 944,648 K2b1 POP07 4790–4558 calBCE M 861,721 U5b2b I2a2a POP08 4700–4300 BCE F 805,956 U8b1a1 POP09 F 867,653 K1a4 POP11 F 865,887 T2b3 POP12 F 841,209 T2b POP13 F 800,065 T2c1d1 POP14 4763–4536 calBCE F 913,421 N1a1a1 POP16 4700–4300 BCE F 825,473 N1a1a1a2 POP19 F 878,975 N1a1a1a3 POP24 M 795,338 K1a1a I2a2a POP27 F 837,294 T2b21 POP30 M 805,808 T2b11 G2a2a POP33 4603–4071 calBCE M 710,341 K1a1 G2a2b2a1a1 POP35 4584–4458 calBCE M 774,710 J2b1a5 C1a2b POP36 4700–4300 BCE M 759,163 H G2a2a POP39 Beli Manastir-Popova zemlja Copper Age 2859 – 2502 calBCE Croatia_Pop_CA F 981,784 HV9 POP23 Beli Manastir-Popova zemlja Roman Period 260–402 calCE Croatia_Pop_RomanP M 962,966 T2f2 R1a1a1b2a2b1 JAG06 Jagodnjak-Krčevine Middle Bronze Age Southern Transdanubian Encrusted Pottery Culture 1800–1600 BCE Croatia_Jag_MBA M 846,845 T2b11 G2a2a1a2a2a1 ~ JAG34 1879–1642 calBCE M 919,781 K2a G2a2a1a2a2a1 ~ JAG58 1800–1600 BCE M 762,207 T2b11 G2a2a1a2a2a1 ~ JAG78 M 922,257 U5b1b1a G2a2a1a2a2a1 ~ JAG82 M 869,661 U2e1a1 G2a2a1a2a2a1 ~ JAG85 F 734,912 K1b1b1 JAG93 F 807,256 U5a1g Back to article page Scientific Reports (Sci Rep) ISSN 2045-2322 (online)
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Post by Admin on Aug 21, 2021 21:01:07 GMT
We conducted all sampling and processing of samples in dedicated ancient DNA laboratories (Methods). We generated whole-genome shotgun data from petrous bone to ~ 1X coverage and aligned fragments to the reference human genome (Methods). We then called pseudo-haploid genotypes using the positions of approximately 1.24 million genome-wide single nucleotide polymorphisms (SNPs) (Methods). As samples were non-UDG treated, we limited analyses to transversion-only SNP sites to mitigate against erroneous genotype calls caused by ancient DNA damage. We confirmed DNA molecules were ancient by observing short read lengths and damage patterns at the ends of reads typical in ancient molecules (Table 1, Supplementary Table S1, Methods). Mitochondrial and nuclear DNA contamination estimates did not exceed 2% for all individuals (Table 1, Supplementary Table S1, Methods). All samples therefore passed quality control measures, and were included for further population genetic analysis. Genetic sexing identified fifteen female and thirteen male individuals (Table 1, Supplementary Fig. S1, Supplementary Table S1). We merged the data from the newly reported individuals with a published worldwide dataset of 1311 present-day individuals genotyped on the Human Origins (HO) array30 (Methods), and data from 1102 published ancient individuals (Methods, Supplementary Table S2) after filtering for contaminated samples and first-degree relatives. All passing individuals had at least 700,000 SNPs available for downstream analyses (Table 1). Genetic transformations from the Neolithic to Roman times In order to understand the genetic affinities of the samples, we performed principal components analysis (PCA) (Methods) by projecting the new shotgun data and published ancient datasets onto the first two principal components constructed from 920 individuals selected from contemporary West Eurasian populations in the Human Origins (HO) dataset30 (Methods, Fig. 2). We also performed model-based clustering analysis in an unsupervised mode with ADMIXTURE (Methods) using 1311 present-day individuals taken from a panel of worldwide populations (Supplementary Fig. S2). Figure 2 West Eurasian PCA. PCA plot of 59 modern West Eurasian populations with a projection of new individuals from this study and selected published ancient genomes using shrinkmode in smartpca. New samples from this study are indicated with a black outline. Present-day Croatian samples are shown as filled dark purple round points. One previously published individual, Croatia_Vučedol_CA, (I4175, see Supplementary Table S2) is labelled “outlier” in the PCA and was excluded from further analysis based on its position in the PCA, low coverage and lack of radiocarbon date. Plot produced using R 3.5.2102. The newly-reported individuals fall along the European cline in PCA space, extending between Neolithic agriculturalist and Bronze Age pastoralist populations. Croatia_Pop_MN clusters tightly with other southeast and central European Neolithic and Copper Age individuals, including Copper Age Croatians from Radovanci and Vučedol, who were merged for further analysis into Croatia_North-East_CA, and share similar ADMIXTURE profiles that exhibit a major contribution from Anatolia-related ancestry (Anatolia_N) and a small contribution of Western European hunter-gatherer (WHG)-related ancestry (Supplementary Fig. S2). We also merged Croatia_Pop_MN and Croatia_Osijek_MN to form Croatia_North-East_MN for further analysis, before testing shared drift with other ancient and modern West Eurasian populations with outgroup f3-statistics of the form f3(Croatia_North-East_MN, Test; Mbuti.DG) (Supplementary Fig. S3a-b, Supplementary Table S3, Methods). This group shares most genetic drift with other Neolithic populations from the Balkans and Central Europe, and present-day Sardinians. We then quantified admixture proportions with qpAdm using distal sources of WHG and Anatolia_N to represent Mesolithic hunter-gatherer and Anatolian Neolithic farmer ancestries that are known to have contributed to European genomic diversity (Methods). We were able to model Croatia_North-East_MN as a mixture of 2.4 ± 1% WHG and 97.6 ± 1% Anatolia_N, and even a 100% Anatolia_N model fits the data (p = 0.11), which is congruent with previous studies that show very low WHG introgression in the Balkans and Hungarian Neolithic3,31 (Fig. 3a, Supplementary Fig. S4, Supplementary Table S4). Using Iron Gates hunter-gatherers (Iron_Gates_HG) instead of WHG produced very similar results (Supplementary Table S4). Using DATES (Methods), we estimated the timing of this admixture to between 19 and 42 generations before the contextual date of the samples (Supplementary Fig. S5, Supplementary Table S5, Methods), corresponding to the Early Neolithic. This further supports population continuity during the Middle Neolithic, in contrast to Middle Neolithic populations from central and Western Europe which show additional WHG gene flow during this time31. Figure 3 Admixture and genetic affinities in ancient Croatian genomes. (a) Distal admixture models obtained with qpAdm for ancient Croatian genomes (Source data in Supplementary Table S4). Smaller points represent individuals and larger points represent population groups with one and three standard error bars indicated for the WHG component. Each population group is labelled with its p-value and the group is encircled for clarity. Croatia_North-East_MN results are for nested two-way models with sources WHG and Anatolia_N, Croatia_Pop_CA is modelled with Anatolia_N and Yamnaya_Samara, and the remainder are three-way models using sources WHG, Anatolia_N and Yamnaya_Samara. b) Proximal admixture models for Croatia_Pop_CA and Croatia_Jag_MBA using qpWave and qpAdm (Source data in Supplementary Table S4). Error bars are one standard error in each direction. (c) UMAP plot of selected post-Neolithic genomes from southern and central Europe. Present-day populations from the Human Origins dataset are indicated with text; ancient genomes are indicated with points as per PCA symbols in Fig. 2. All plots were produced using R 3.5.2102. We grouped the new Copper Age individual, POP39, with a previously published cladal individual, I3499 (Supplementary Table S2, Supplementary Table S6), who originates from the same site and time period (Croatia_Pop_CA). This group is shifted further up along PC2 and clusters with three previously reported Bronze Age samples from coastal Dalmatia (Croatia_Dal_BA), falling within the wide distribution of Bulgarian and Hungarian Bronze Age genomes and present-day southern Europeans in PCA space (Fig. 2) suggesting the presence of steppe-related ancestry. Indeed, distal admixture modelling with qpAdm estimates a contribution of 71 ± 8% from Anatolia_N and a further 29 ± 8% from Yamnaya_Samara, representing steppe-related ancestry absent in the Neolithic but found widely among Eurasian Copper and Bronze Age populations. (Fig. 3a, Supplementary Fig. S4, Supplementary Fig. S6, Supplementary Table S4). We obtained a feasible two-way admixture model with the more proximal, broadly contemporaneous pre-steppe group Croatia_North-East_CA (64 ± 8%) and Yamnaya_Samara (36 ± 8%) (Fig. 3b, Supplementary Table S4). We considered the newly-reported Middle Bronze Age genomes from Jagodnjak (Croatia_Jag_MBA) a single group for further population genetic analysis based on common archaeological context and clustering on the PCA (Fig. 2). We observe a marked shift left along PC1 towards Western and Iron Gates hunter-gatherers, with which it shares the most drift in outgroup f3-statistics (Supplementary Fig. S3, Supplementary Table S3). Distal admixture modelling using sources WHG, Anatolia_N and Yamnaya_Samara confirms a large WHG component in Croatia_Jag_MBA (20 ± 2%), in contrast to Croatia_Pop_CA, and is more than double the fraction estimated for the broadly contemporaneous Dalmatian Bronze Age (Fig. 3a, Supplementary Fig. S4, Supplementary Table S4), also consistent with the significantly positive F4 tests of the form f4(Mbuti.DG, WHG; Croatia_Dal_BA, Croatia_Jag_MBA) (Z = 6.95) (Supplementary Table S7). The Jagodnjak group also harbours slightly greater steppe-related ancestry compared to the preceding Croatia_Pop_CA at 33 ± 5% (see also Supplementary Fig. S6), consistent with previous findings for the Balkan region2. Replacing WHG with Iron_Gates_HG harbours comparable results (Supplementary Table S4). This group falls at the left side of the wide distribution of Bronze Age populations from the Carpathian Basin in PCA space, as well as present-day NW European genomes such as French, suggesting an eastward expansion of the Western Bronze Age signature. To further characterise differential genetic affinities of the Jagodnjak group to the Dalmatian Bronze Age and other genomes, we visualised genetic substructures among post-Neolithic genomes from the region with increased resolution using UMAP and default parameters (Fig. 3c, Methods). While UMAP does not reflect genetic distances in a linear way, clearly defined clusters become apparent, in which Croatia_Pop_CA and Croatia_Dal_BA cluster with ancient genomes from Bulgaria, Montenegro, Romania and some Hungarians together with predominantly present-day Italian_North genomes, pointing to a genetic profile consistent with southern Europe. Testing with qpWave confirmed that Croatia_Pop_CA provides a feasible single source of ancestry for the Dalmatian Bronze Age (Supplementary Table S4). Croatia_Jag_MBA contrastingly falls to the left of present-day genomes from Hungary, Germany, Czech Republic and Croatia, indicating a Central European genetic signature. Other ancient genomes in this cloud also include individuals from the Carpathian Basin belonging to Makó EBA, Vatya MBA, and an LBA individual. The excess WHG-related ancestry present in Middle Bronze Age Jagodnjak suggests that this group descends from populations harbouring additional WHG-related ancestry that is lacking in the preceding Croatian Copper Age or Dalmatian Bronze Age, consistent with qpAdm modelling (Fig. 3b, Supplementary Table S4). Archaeological evidence points to exchange networks between the Middle Bronze Age communities of eastern Croatia and other cultural groups further north29. Based on its date and core distribution in the Carpathian Basin32, as well as its clustering with Croatia_Jag_MBA in UMAP and PCA space, we considered Hungary_Makó_EBA the most suitable candidate source of ancestry. This choice is further supported by Hungary_Makó_EBA sharing similar amounts of drift with WHG to Croatia_Jag_MBA (Supplementary Fig. S7, Supplementary Table S3). We indeed obtained feasible models with Hungary_Makó_EBA, either as a two-way model with 35 ± 11% contribution from Croatia_Pop_CA or as a single source (Fig. 3b, Supplementary Table S4). For Croatia_Jag_MBA we estimated the date of admixture between WHG and Anatolia_N as 41 ± 13 generations before the combined radiocarbon and contextual date of the population (Supplementary Fig. S5, Supplementary Table S5). This is consistent with a calendar date range of 3424—2412 BCE, which overlaps with the Copper Age. We also explored potential sex bias in the inheritance of ancestral components with qpAdm applied separately to autosomes and the X chromosome. While results are consistent with no significant sex bias (-1 < Z-score < 1), the large standard errors in such analyses may hide low or moderate differences between the sexes (Supplementary Table S8, Methods).
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