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Post by Admin on May 10, 2024 2:20:32 GMT
CLV IMPACT IN THE CAUCASUS AND ANATOLIA CLV Cline people also had an impact further south, in Armenia and Anatolia (Fig. 2f). The earliest evidence of steppe ancestry south of the Caucasus is at Areni-1 in Chalcolithic Armenia around 4000 BCE9, documenting its southward penetration which parallels the incursion of Caucasus ancestry generating the Volga/Dnipro clines on the steppe. Our analysis (Supplementary Information section 2) clarifies that in Areni-1 the Lower Volga ancestry (26.9±2.3% BPgroup) admixed with a local “Masis Blur”-related Neolithic substratum, in contrast to the North Caucasus (at Maikop) where it combined with an “Aknashen”-related Neolithic substratum. The Aknashen/Masis Blur distinction of the Neolithic population of Armenia reflected the dilution of the native CHG ancestry that was higher in Aknashen than in Masis Blur.6 We can model Masis Blur as 33.9±8.6% Aknashen and 66.1±8.6% Çayönü ancestry (p=0.47) associated with the Pre-Pottery Neolithic of the Tigris Basin of Mesopotamia46, thus documenting the spread of early Neolithic ancestry into the Caucasus that formed a cline of diminishing Mesopotamian-related and increasing CHG-related ancestry: Çayönü-Masis Blur-Aknashen. Using CHG as the source, we see that the two populations from Armenina differed indeed in their retention of CHG ancestry, with more (42.0±3.8%) in Aknashen than in Masis Blur (13.7±4.0%). Some Anatolian Chalcolithic and Bronze Age groups can be derived entirely from this north-south Caucasus-Mesopotamian cline (Fig. 2f), while others also have ancestry from the east-west Mesopotamian-Anatolian cline, lacking any steppe ancestry.22,43,45,47,48 The discovery of the Mesopotamian-Caucasus cline allows us to study the ancestry of the population of Bronze Age Central Anatolia22 from the Early Bronze Age (2750-2500 BCE), Assyrian Colony (2000-1750 BCE), and Old Hittite (1750-1500 BCE) periods. We cannot be certain of what languages were spoken by these individuals in what may well have been multilingual societies, but we document for the first time that they had a small amount of CLV cline ancestry combined with Mesopotamian (Çayönü) ancestry (Supplementary Information, section 2; Fig. 2f; Extended Data Fig. 1). The inferred amount of ancestry from the CLV or CLV-influenced source depends on the amount of “dilution” of this ancestry in the source: more such ancestry is required from populations of higher dilution. For example, it is estimated as 10.8±1.7% ancestry (p=0.14) from the BPgroup, or about double 19.0±2.4% from Remontnoye (p=0.19)—whose own ancestry is about half from the BPgroup—or 33.5±4.8% of Armenia_C ancestry (p=0.10)—where the BPgroup ancestry is lower. Extended Data Figure 1:  The origin of Central Anatolian Bronze Age. (a) Fitting models include Mesopotamian (Çayönü) and steppe ancestry. (b) Models with western sources from Southeastern Europe fail except those with Mayaky or Boyanovo EBA sources both of which are Yamnaya-derived. (c) The steppe (BPgroup)+Çayönü model fails all Chalcolithic/Bronze Anatolians except Central Anatolian Bronze Age. (d) Steppe (BPgroup) ancestry observed in all individuals of the Central Anatolian Bronze Age (±3s.e. shown). (e) BPgroup-related ancestry admixed with different substrata: Aknashen-related in the North Caucasus Maikop, Masis Blur-related in Chalcolithic Armenia, and Mesopotamian-related (Çayönü) in the ancestors of the Central Asian Bronze Age, following the route (f) from the North Caucasus to Anatolia. |
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Post by Admin on May 11, 2024 20:30:08 GMT
 Extended Data Figure 2: Admixture time estimates. We estimate admixture times for the Core Yamnaya as a mixture of European hunter-gatherer and West Asian populations (a), for the Don Yamnaya as a mixture of Core Yamnaya and UNHG (b), for the Bulgaria-Moldova-Romania-Serbia (BMRS) Yamnaya as a mixture of Core Yamnaya and European Neolithic/Chalcolithic farmers (c), for the Corded Ware as a mixture of Core Yamnaya and Globula Amphora (d), and for Caucasus-Anatolia populations (Maikop-Armenia_C-TUR_C_BA) as a mixture of European hunter-gatherer and West Asian populations which occurred ca. 4400BCE (e). The Core Yamnaya were formed ca. 4000BCE, followed by admixture ca. 3350 BCE with UNHG and European farmers in the east and west of the Dnipro-Don region and <3000BCE in central-eastern Europe. How and when did this blend reach Central Anatolia? We note that populations along the path from the steppe to Central Anatolia can all be modeled with BPgroup ancestry and distinctive substratum ancestries along the north-south / Caucasus-Mesopotamia cline: Aknashen-related in the North Caucasus Maikop; Masis Blur-related in the South Caucasus Chalcolithic population of Armenia at Areni-1; and Mesopotamian Neolithic for the Central Anatolian Bronze Age (Extended Data Fig. 1e, f). This series of admixtures had certainly begun by ca. 4300-4000BCE (the date range of the Armenia_C population9) and can be dated using DATES to 4382±63BCE (Extended Data Fig. 2f). The Pre-Pottery Neolithic population of Çayönü was itself genetically halfway between that of Mardin10, 200km to the east, and the Central Anatolian pottery Neolithic at Çatalhöyük along the east-west / Mesopotamian-Anatolian cline. Chalcolithic/Bronze Age people from Southeastern and Central Anatolia all had ancestry from the same Çatalhöyük-Mardin continuum and such populations may have been proximal sources for the Çayönü-related ancestry of the Central Anatolian Bronze Age population (Supplementary Information section 2). If the Proto-Anatolian population was formed in this region by the admixture of CLV cline people with Mesopotamian ones then their descendants may have been present there at the unknown site of Armi whose Anatolian personal names are recorded by their neighbors in the kingdom of Ebla in Syria.50 We thus propose the following hypothesis: that CLV cline people migrated southwards ca. 4400BCE, or about a millennium before the appearance of the Yamnaya, (admixing with different substratum populations along the way) and then westwards before finally reaching Central Anatolia. We in fact find Y-chromosome evidence that is consistent with the autosomal evidence. Sporadic instances of the steppe-associated Y-chromosome haplogroup R-V1636 in West Asia occurred at Arslantepe43 in Eastern Anatolia and Kalavan9 in Armenia in the Early Bronze Age (∼3300-2500 BCE) among individuals without detectible steppe ancestry45 and these could be remnants of the dilution process. This haplogroup was found in the male individual from Remontnoye, both individuals from Progress-25 and two of three males from Berezhnovka, in addition to its occurrence in eleven individuals of the Volga Cline and thus was a prominent lineage of the pre-Yamnaya steppe. Isolated instances have also been found beyond the steppe in Corded Ware individuals from Esperstedt in Germany17 and Gjerrild in Denmark.51 The expansive distribution of R-V1636 on the steppe and beyond contrasts with its disappearance on the steppe after the Yamnaya arrived on the scene: a single individual (SA6010; 2886-2671 BCE) from Sharakhalsun5 has it, with a genetic profile consistent with CLV ancestry (Fig. 2), the last detected holdout of this once pervasive population (Fig. 3). |
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Post by Admin on May 14, 2024 22:25:22 GMT
 Figure 3. Patrilineal succession. Temporal distribution of key Y-chromosome haplogroups from Kazakhstan, Kyrgyzstan, Mongolia, Russia, Turkmenistan, Ukraine, Uzbekistan, and comparative regions of Europe and West Asia 6000-1000 BCE. The Early and Middle Bronze Age group includes the Yamnaya, Afanasievo, Poltavka, Catacomb, Chemurchek, and North Caucasus cultures; the Middle and Late Bronze Age group individuals of diverse cultures down to 1000 BCE including those of the Sintashta, Andronovo, Potapovka, and Srubnaya cultures. The Yamnaya expansion broke correlations between geography and genetics We have traced the origins of the Yamnaya to the Dnipro Cline and the populations of the Serednii Stih culture: the Yamnaya were formed as people of the CLV cline admixed with people of the Dnipro-Don area having UNHG ancestry. Deeper in time, the CLV cline was formed by the admixture of Aknashen-related and BPgroup-related people who, in turn, were formed by earlier mixtures still: the Caucasus Neolithic represented at Aknashen by the admixture of CHG people with Neolithic farmers of the Fertile Crescent6,10 and the lower Volga Eneolithic people represented by BPgroup had ancestries that were related to CHG, EHG, and people from Siberia or Central Asia. Dating this complex sequence of admixtures could be done by generating time transects of fine resolution in all relevant areas from which the ancestors of the Yamnaya were drawn across the millennia until they finally combined to form the Yamnaya genetic profile somewhere in the territory of the Serednii Stih culture: seeing the admixture “as it happened” through the lens of ancient DNA. Our study has revealed the outlines of this millennia-long process and future studies may fill in the details. A different way is to date the admixture itself in the genomes of the Yamnaya using methods like DATES52 to measure the average sizes of stretches of ancestry related to UNHG/EHG hunter-gatherer populations on the one hand, and West Asian/Caucasus-related populations on the other, as this reflects the number of generations elapsed since mixture began and stretches of ancestry broke down. This population contrast aligns to the differentiation along PC2 (Fig. 1). We would also like to model the Core Yamnaya in terms of ancestry along the Dnipro cline itself (their last and most proximal admixture event), but unfortunately this is challenging given that the Yamnaya themselves are the end of the Dnipro cline (Fig. 1). The inferred date of 4038±48 BCE (Extended Data Fig. 2a) should thus be viewed with caution given the complex history of the ancestors of the Yamnaya, and admixture may have taken place both before and after this date. Nonetheless, an Eneolithic time frame (with a small standard error of <2 generations) proves that the admixture derived using qpAdm and observed visually in PCA did not occur in the remote past, but corresponds, at least in part, to the efflorescence of the Serednii Stih culture that our reconstruction points to as ancestral to the Yamnaya. Uncertainty about where, exactly, within the territory of the Serednii Stih culture the ancestors of the Core Yamnaya lived contrasts with their expansive distribution after the formation of the Yamnaya archaeological horizon: individuals we identified as “Core Yamnaya” (Extended Data Table 2) cluster in a small portion of the PCA (Fig. 1) and are from several countries: China, Hungary, Kazakhstan, Moldova, Romania, Ukraine (Extended Data Table 2), and 15 different locations in Russia (Fig. 4a). The homogeneity is also evident in a mean FST of 0.005, comparable to that between modern northern Europeans (Extended Data Table 3). This remarkable homogeneity across vast geographical distances of the “eastern” expansion of the Yamnaya shows that many of them mixed very little if at all with any of the people that inhabited the Eurasian steppe before them. The Don Yamnaya (Fig. 4a) are distinctive and can be modeled with 79.4±1.1% Core Yamnaya and 20.6±1.1% UNHG ancestry; the actual proportion of Core Yamnaya ancestry may be lower if, as is plausible, the Core Yamnaya admixed with a Serednii Stih population of partial UNHG ancestry (e.g., 40.0±4.7% with SSmed as the Serednii Stih source). The Don Yamnaya were formed in the late 4th millennium BCE (Extended Data Fig. 2b), a time during which unmixed UNHG, after a millennium or more of the Serednii Stih culture, would be rare if they existed at all. |
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Post by Admin on May 17, 2024 13:11:57 GMT
 Extended Data Table 2: Extraordinary Genetic Homogeneity in the Core Yamnaya. We tested all populations and individuals for cladality with Samara Yamnaya. We list populations for which this is not rejected (p>0.05) and populations that include individuals that fit Core Yamnaya selection criteria (p>0.2, at least 300k SNPs, and Yamnaya or Afanasievo culture). |
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Post by Admin on May 18, 2024 22:13:47 GMT
Extended Data Table 3: FST values among populations that include Core Yamnaya individuals. FST values are shown below the diagonal and their standard errors above it.   Figure 4: Population structure in people with a Yamnaya cultural affiliation. Individuals are projected in the same space as in Fig. 1. (a) showing that the Core Yamnaya cluster (black symbols) from diverse sites is differentiated from the Don Yamnaya (blue) who tend towards the UNHG. (b) Yamnaya individuals in the West (Ukraine, Hungary, Slovakia, and Southeastern Europe) include a tight cluster of individuals as well as others that tend towards the direction of European Neolithic and Chalcolithic groups from Romania and Hungary. Individuals from Russia are shown in grey circles in panel (b). The western expansion of the Core Yamnaya also brought them into southeastern Europe; Yamnaya there or other individuals of “high steppe ancestry” can be found as far west and south as Albania and Bulgaria.6 Many western Yamnaya cluster with the Core Yamnaya, but many also deviate in the direction of Neolithic and Chalcolithic populations of southeastern and central Europe (Fig. 4b) and can be modeled with admixture from such populations (Extended Data Table 4). This admixture also took place in the late 4th millennium BCE (Extended Data Fig. 2c), after the sporadic early Chalcolithic migrations into southeastern Europe from the steppe.36 It is interesting that after the Don Yamnaya formed they participated little or not at all in the Core Yamnaya expansion to either the Altai or SE Europe, and thus the Lower Don represented a cul-de-sac for the Yamnaya expansion.  Extended Data Table 4: qpAdm models that fit non-Core Yamnaya. We use the following sources to model Yamnaya-related populations other than the Core and Don Yamnaya: CoreYamnaya, Romania_C_Bodrogkeresztur, Romania_N, Serbia_IronGates_Mesolithic, Trypillia, Ukraine_N, Usatove. The Baden individuals from Hungary represent a reburial into a kurgan82 and are predominantly of European farmer, not Yamnaya, ancestry. The Riltsi individual is shown with Usatove ancestry here and can also be modeled with about half Remontnoye ancestry, as the Usatove have ancestry from the CLV cline.15 The late 4th millennium BCE admixtures with European farmers and UNHG-admixed populations frame the Dnipro-Don region from west and east, providing another line of evidence for the formation of the Yamnaya within this region. Y chromosome haplogroup sharing—which traces the entirely male line and is of particular interest in societies that have patrilineal traditions—(Fig. 3) is less informative for tracing the origins of the Core Yamnaya, but proves continuity of the Don Yamnaya with their Serednii Stih ancestors. Haplogroup I-L699 was an important lineage in the Dnipro area since the Neolithic hunter-gatherer period, continued to be prevalent among the Serdenii Stih, and in the Don Yamnaya was dominant (17/20 instances). The Core Yamnaya belonged primarily to haplogroup R-M269 (49/51 instances) most of which could be determined as belonging to the Z2103 sub-lineage (41/51). This lineage is unprecedented in our sampling of the steppe before the Yamnaya period; its closest relative is the L51 lineage which dominated the Beaker group3 and mainland Europe outside the steppe (Fig. 3), with a slightly more distant relative in the R-PF7563 lineage found in Pylos in Mycenaean Greece.45 With an estimated time of formation of ∼4450 BCE (https://www.yfull.com/tree/R-L23/; v11.04.00), the R-L23 lineage unifies Beaker, Yamnaya, and Mycenaean Y-chromosomes within an Eneolithic timeframe, which is consistent with the ancestors of these three groups being part of a single population in the Yamnaya period itself since population divergences are always lower than the genetic divergences of specific haplotypes. It is a challenge for future ancient DNA studies to find the population in which the Eneolithic R-L23 founder lived and to trace his R-Z2103 descendants. Their absence from the Eneolithic record, together with the evidence (discussed below) for isolation in the formative period of the Yamnaya suggest that he might have been part of a small group not yet sampled. That the Core Yamnaya are part of the Dnipro cline may suggest an origin in the Dnipro basin itself, but (a) the Dnipro cline is generated by admixture with Dnipro-Don people (UNHG/GK2-related), and (b) the Yamnaya on the Don are also part of this cline, so an alternative origin in the Don area cannot be excluded. An origin of the Core Yamnaya further east, in the Caucasus-Volga region is unlikely given that they are not part of the Volga or CLV Clines. Conversely, placing Yamnaya origins west of the Dnipro is implausible as the Core Yamnaya are the population of the Dnipro Cline that is maximally derived from the eastern CLV Cline and they also do not have the European farmer-derived ancestry of western populations such as the Usatove (Fig. 1b).15 The Core Yamnaya share ancestry with people of the whole Dnipro-Don-Volga-Caucasus region, but their ancestral mix includes all components also found in the Serednii Stih, while these are lacking elsewhere (Extended Data Fig. 3). A more western origin of the Core Yamnaya would also bring their latest ancestors in proximity to the place of origin of the Corded Ware complex whose origin is itself in question but must have certainly been in the area of central-eastern Europe occupied by the Globular Amphora culture west of the Core Yamnaya. The Corded Ware population, which could trace a large part of its ancestry to the Yamnaya,2 was formed by admixture concurrent with the Yamnaya expansion52 (Extended Data Fig. 2d), shared segments of IBD proving connections within a shallow genealogical timeframe, and had a balance of ancestral components from the Caucasus and eastern Europe indistinguishable from the Yamnaya.6 In combination, these lines of evidence suggests that it was formed indeed by early 3rd millennium BCE admixture with Yamnaya, or, at the very least, genetically Yamnaya ancestors that need not have been Yamnaya in the archaeological sense. The geographical homelands of the Corded Ware and Yamnaya would then conceivably be in geographical proximity to allow for their synchronous emergence and shared ancestry. The Dnipro-Don area of the Serednii Stih culture fits the genetic data, as it explains the ancestry of the nascent Core Yamnaya and places them in precisely the area from which both Corded Ware, and Southeastern European Yamnaya (in the west) and the Don Yamnaya (in the east) could have emerged by admixture of the Core Yamnaya with European farmers and UNHG respectively. |
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