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Post by Admin on Sept 22, 2022 1:41:31 GMT
Our newly reported data reveal that a large proportion of individuals inArmenia and Northwest Iran belonged to the R-Z2103→R-M12149 haplogroup during the 2nd and early 1st millennium BCE, providing a genetic link with the Yamnaya in these regions where no archaeological presence of the Yamnaya culture itself is attested. It definitely represents a more direct link than either R-V1636 or the early appearance of Eastern hunter-gatherer ancestry at Areni-1 cave in Armenia (10) during the Chalcolithic at the end of the 5th millennium BCE, which provides evidence of conversemovement of Caucasus hunter-gatherer ancestry into the steppe Eneolithic. Despite the Y-chromosomemovement southward attested by our data, any association between R-haplogroup bearers and Eastern hunter-gatherer ancestry was lost south of the steppe because these had similar proportions of Eastern hunter-gatherer ancestry as I-Y16419 bearers (the second most prevalent lineage in Armenia). Two Bronze-to-Iron Age sites with substantial sample sizes [unrelated males from Bagheri Tchala (n = 7) and Noratus (n = 12)] have contrasting haplogroup distributions dominated by R-M12149 and I-Y16419, respectively (Fisher’s exact test P < 0.001), suggesting founder events, high genetic drift, or a patrilocal mating system ~1000 BCE in Armenia. During the same period atHasanlu in Northwest Iran, many individuals have no trace of Eastern hunter-gatherer ancestry at all despite the presence of R-M12149 there (6), suggesting that the initial association of this lineage with Eastern hunter-gatherer ancestry on the steppe had vanished as R-M12149 bearers reproduced with Southern Arc individuals without Eastern hunter-gatherer ancestry (Fig. 6C). We observe that, on the steppe, R-M12149 Y chromosomes (within haplogroup R1b) at
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Post by Admin on Sept 23, 2022 6:40:58 GMT
the beginning of the 3rd millennium BCE, associated with the Yamnaya, were replaced by the beginning of the next millennium by R-Z93 Y chromosomes (within haplogroup R1a), associated with Corded Ware/Fatianovo (35) steppe descendants such as those of the Sintashta culture (34). Genetic data cannot distinguish whether this Y-chromosome replacement was the result of competition between patrilineal groups from the steppe, one of which may have had cultural adaptations such as usage of an improved variety of domesticated horse (37), or whether one group simply filled an ecological niche vacated by earlier groups. A fuller understanding of the reason for this profound genetic change requires combined analysis of genetic and archaeological data. Whatever the reason for their demise on the steppe itself, the Yamnaya-descended R-Z2103 patrilineages survived in Armenia down to the present day, where this clade is present in appreciable frequencies in all studied Armenian groups (38) despite the substantial dilution of autosomal steppe ancestry documented in our study. The persistent and lasting presence of Yamnaya patrilineal descendants in Armenia contrastswithmainland Europe and South Asia, where steppe ancestry was introduced by people who were not patrilineal descendants of the dominant R-M12149 lineage of the Yamnaya population. Instead, they belonged to different descent groups who had received autosomal steppe admixture while carrying different predominant Y-chromosome lineages. Armenia also contrasts with Anatolia, for which no R-M269 Y-chromosomes are observed at all during the Chalcolithic, Bronze Age, or Ancient (pre-Roman) periods [n = 80 unrelated individuals; 95% confidence interval (CI): 0 to 4.5%] and in which haplogroups J (36 individuals) and G (17 individuals) are most common Haplogroup J is still common at a frequency of about one-third in present-day people from Turkey (39), having achieved such prominence despite occurring in only in one in 18 Neolithic male individuals from Barcın and Ilıpınar in theMarmara region during the pre-Chalcolithic period. A likely explanation for the haplogroup J increase is that it accompanied the spread of Caucasus hunter-gatherer ancestry inferred by our admixture analysis (Fig. 2). This inference is made plausible by the fact that both Caucasus hunter-gatherer individuals from Kotias and Satsurblia (7) and a Mesolithic individual from Hotu Cave (10, 34) in Iran belonged to this lineage, suggesting its very old presence in the Caucasus/Iran region, and in contrast with haplogroup G, which occurred in themajority (10/18) of individuals from the Neolithic Marmara region. By the Chalcolithic, haplogroups G and J were ubiquitous in Anatolia, each making up 10/28 males from that period, paralleling the homogenization that had occurred by that time.
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Post by Admin on Sept 26, 2022 4:04:42 GMT
The Indo-Hittite hypothesis in the light of genetic data We discuss the implications of our genetic findings for hypotheses about the origins and spread of Indo-European and Anatolian languages. We also highlight a caveat: In contrast to findings about movements of people, the relevance of genetics to debates about language origins is more indirect because languages can be replacedwith little or no genetic change and populations can migrate and mix with little or no linguistic change. Nevertheless, the detection of migration is important because it identifies a plausible vector for language change (40). The discoveries of massive migrations from the steppe both westward into Central and Western Europe (4, 8), and eastward into South Siberia (4) and Central/South Asia (34), have provided powerful evidence for the theory of steppe Indo-European origins by linking populations all the way from Northwest Europe (36) to IndiaandChinathroughcommonsteppe ancestry. The present study adds further support to the theory by thediscovery of ubiquitous ancestry from the steppe in the Bronze Age Balkans [where, indubitably, Indo-European Paleo-Balkan languages such as Thracian and Illyrian (41) were spoken], including individuals of predominantly steppe ancestry; by documenting the ubiquity of steppe ancestry in Bronze and Iron Age Armeniawhere Armenian is first attested and links between Armenia, the steppe, and the Balkans; and by the further documentation of steppe ancestry in the Aegean (6) during the Mycenaean period when the Greek language is first attested, albeit at lower levels. All ancient and present-day branches of the Indo-European language family can be derived or at least linked to the early Bronze Age Yamnaya pastoralists of the steppe or genetically similar populations. A link to the steppe cannot be established for the speakers of Anatolian languages because of the absence of Eastern hunter-gatherer ancestry in Anatolia (4, 10, 14, 16), which our study reinforces in three ways: (i) by documenting its paucity in ~100 new Anatolian individuals from the Chalcolithic to pre-Roman antiquity, (ii) by contrasting western parts of Anatolia with its immediate Aegean-Balkan neighbors to the west, and (iii) by contrasting eastern/northern parts of Anatolia with its neighbors in Armenia in the east. Certainly, the absence of Eastern hunter-gatherer ancestry in Anatolia can never be categorically proven (becausemore sampling can always disclose some such ancestry); however, at present, and despite extensive sampling, such ancestry is not detected either at possible entry points (west and east by land or even north by sea) or in the population as a whole. The Indo-Hittite hypothesis, first proposed by E. H. Sturtevant in 1926 (42), has been partially supported by more modern phylolinguistic analyses, indicating that Anatolian languages such as Hittite are basal to the rest of the Indo- European family tree (43) and suggesting an early split between the two. We have shown that Anatolia was indeed transformed by the Late Chalcolithic through the spread of Caucasus hunter-gatherer–related ancestry to its westernmost edges, as were apparently Eneolithic populations of the steppe, which included also Anatolian/Levantine–related ancestry by the time of the formation of the Yamnaya pastoralists. It is premature to identify the proximate sources of these movements before all the candidate source populations of Anatolia, North Mesopotamia, Western Iran, Armenia, Azerbaijan, and the Caucasus have been adequately sampled.
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Post by Admin on Sept 28, 2022 7:40:42 GMT
Our analyses show that there were at least two gene flows from two groups related to West Asians into the steppe, which transformed the steppe’s population and may have induced linguistic change there. The reversemovement is more tentative, with early influences from the north such as at Areni Cave (10) or possibly associated with R-V1636 Y-chromosomes, not making a sizable genetic impact on the population of Anatolia. The evidence is consistent with two hypotheses. Hypothesis A postulates that Proto-Indo- Anatolian (including both Anatolian languages and Proto-Indo-European) was spoken by a population with high Eastern hunter-gatherer ancestry that had a disproportionate linguistic impact on Anatolia while contributing little if any ancestry. In the post–Bronze Age landscape of Anatolia, we do find outliers marked by European or steppe influence (6),but this is a period when Anatolia is influenced by numerous linguistically non-Anatolian Indo-European populations, including Phrygians, Greeks, Persians, Galatians, and Romans, to name only a few. However, in individuals from Gordion, a Central Anatolian city that was under the control of Hittites before becoming the Phrygian capital and then coming under the control of Persian andHellenistic rulers, the proportion of Eastern hunter-gatherer ancestry is only ~2%, a tiny fraction for a region controlled by at least four different Indo-European– speaking groups. In medieval times, Central Asian ancestry associated with Turkic speakers was added (6), and it persists to the present. Clearly, Anatolia has not been impervious to linguistic change during its recorded history, and the harbingers of that change are also detected genetically, even if as outliers. By contrast, the complete absence of Eastern hunter-gatherer ancestry in the Chalcolithic and Bronze Age either as isolated outliers or as a general low-level presence challenges the steppe theory to suggest a plausible mechanism of how a population that made little, if any, genetic impact could nonetheless effect large-scale linguistic change. A common vocabulary for wheeled vehicles is not attested for both Anatolian languages and the rest of the Indo-European languages (44), thus potentially removing a technological advantage regarded as potentially crucial in the dissemination of Indo-European languages (45).
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Post by Admin on Sept 29, 2022 5:31:15 GMT
Hypothesis B postulates that Proto-Indo- Anatolian was spoken by a population ofWest Asia and the Caucasus with low or no Eastern hunter-gatherer ancestry, which affected both Anatolia and the steppe. Hypothesis B may help to explain the linguistic diversity observed in Bronze Age Anatolia in which both Anatolian (Hittite, Luwian, and Palaic) speakers, as well as speakers of other languages including Hattic (a non–Indo-European linguistic isolate of Central/Northern Anatolia) and Hurrian [a non–Indo-European language from Eastern Anatolia and NorthMesopotamia related to the later Iron Age Urartian language (6)], coexisted. The non–Indo-European Hattic language, attested only in Anatolia, would most economically represent the linguistic substratum, spoken by a population of high Anatolian-related ancestry, whereas the Indo- European Anatolian languages would be spoken by a population of high Caucasus hunter-gatherer–related ancestry. The spread of people of high Caucasus hunter-gatherer ancestry across the peninsula from the east, at least some of whom may have spoken early forms of Anatolian languages, would simultaneously explain both the genetic homogenization before the Late Chalcolithic (Fig. 2) and the coexistence of the two linguistic groups. How many of the peoples associated with the spread of Caucasus hunter-gatherer ancestry spoke Anatolian languages? People speaking other languages related to the diverse non–Indo- European language families of the Caucasus, such as Kartvelian and Northwest/Northeast Caucasian, may have also participated in the westward movements. As for the steppe, at least two streams of migration from the south (Eneolithic and Yamnaya-specific) present the opportunity for an early (Chalcolithic) split of Yamnaya linguistic ancestors from the Anatolian linguistic ancestors, followed 1000 to 2000 years later by the dispersal of Indo-European languages from the steppe with the expansion of the Yamnaya culture. Linguistic borrowings (46) between Proto-Indo-European and other language families such as Kartvelian (spoken primarily in Georgia) could be useful for localizing the Proto-Indo-Anatolian homeland, but these may have alternatively come about by long-range mobility since the Chalcolithic, proven by such evidence as the presence of R-V1636 descendants ~3000 km apart from Khvalynsk to Anatolia during this period. Contributions of Indo-European to Uralic languages (spoken in the forest zone of Eastern Europe and Siberia) appear to have involved only Indo-Iranian speakers ~4200 years ago (47). This is important because it constrains the migratory history of Proto-Indo-Iranian, consistent with genetic evidence (34) that it spread through the steppe to South Asia and ruling out the possibility that it spread from West Asia to South Asia over the Iranian plateau. However, the contribution of Indo-Iranian to Uralic languages does not shed light on the deeper question of early Indo- Anatolian origins. A challenge for the theory that Proto-Indo-Anatolian was formed in the south in a Caucasus hunter-gatherer–rich population will be to trace the origins of the autosomal ancestry of the Yamnaya in the Caucasus or West Asia [where some existing proposals place the Proto-Indo-Anatolian homeland (32, 48, 49)] and to identify the place from which the R-M269 ancestral lineage expanded, because this will be amost plausible secondary homeland of Indo-European expansion outside of Anatolia.
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