The Southern Arc – a bridge between Europe and Asia
Some of the earliest civilizations emerged and flourished in the ‘Southern Arc,’ a geographic region that stretches from the Caucasus and the Levant, across Anatolia and the Aegean into the Balkans; forming a bridge between Europe and Asia.
Across this arc various ancient human cultures formed, and spread. These cultures, whether lost to history or surviving down to the present day, are not only the heritage of the people of the region, but made a profound impact on human civilization as a whole.
At present, our knowledge about the people of many of these cultures, their movements, mating patterns and languages, is patchy. Paleogenetic research can cast new light on the lifeways of the people of past societies and the spread and diversification of their languages. However, addressing big questions about the past with paleogenetics requires large-scale systematic research which fills many of the current geographic and temporal gaps with which we can piece the puzzle.
In a trio of papers published simultaneously in the journal Science which report genome-wide data from 727 distinct ancient individuals—more than doubling the amount of ancient DNA data from this region and filling in major gaps in the paleogenetic record—a team of researchers led by Ron Pinhasi at the Department of Evolutionary Anthropology and Human Evolution and Archaeological Sciences (HEAS) at the University of Vienna, Songül Alpaslan-Roodenberg at the University of Vienna and Harvard University, and Iosif Lazaridis and David Reich at Harvard University—together with 202 co-authors—leverage their data to test longstanding archaeological, genetic and linguistic hypotheses. They present a systematic picture of the interlinked histories of peoples across this region from the origins of agriculture, to late medieval times.
The homeland and the spread of Anatolian and Indo-European languages
The genetic results about the Chalcolithic/ Copper Age and Bronze Age periods, presented in their first paper “The genetic history of the Southern Arc: a bridge between West Asia and Europe”, suggest that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe. At the first stage, around 7,000-5,000 years ago, people with ancestry from the Caucasus moved west into Anatolia and north into the steppe. Some of these people may have spoken ancestral forms of Anatolian and Indo-European Languages.
All spoken Indo-European languages can be traced back to Yamnaya steppe herders, with Caucasus hunter-gatherer and Eastern hunter-gatherer ancestry, who ~5,000 years ago initiated a chain of migrations across Eurasia, linking Europe in the west to China and India in the east. Their southern expansions into the Balkans and Greece and east across the Caucasus into Armenia left a trace in the DNA of the Bronze Age people of the region.
As they expanded, descendants of the Yamnaya herders admixed differentially with the local populations. The emergence of Greek, Paleo-Balkan, and Albanian (Indo-European) languages in Southeastern Europe and the Armenian language in West Asia, formed out of Indo-European speaking migrants from the steppe interacting with local people, and can be traced by different forms of genetic evidence. In Southeastern Europe, the Yamnaya impact was profound and people of practically full Yamnaya ancestry came just after the beginning of the Yamnaya migrations. “We find in Albania, Bulgaria, Croatia, Serbia people that genetically appear as if they were transplanted from the steppe,” says David Reich. “The connection is unmistakable, and as time went on, the newcomers fused with the locals, leaving more of their ancestry in the north of the Balkan peninsula than in the south, but having a linguistic impact throughout.”
The results show that in contrast to the Balkans and the Caucasus, Anatolia was hardly impacted by the Yamnaya migrations. No link to the steppe can be established for the speakers of Anatolian languages due to the absence of Eastern hunter-gatherer ancestry in Anatolia, contrasting with all other regions where Indo-European languages were spoken.
The Yamnaya herders also crossed the Caucasus and by about 4,000 years ago, and the Armenian plateau was an enclave of low but pervasive steppe influence in West Asia. “We often think of the Yamnaya spreading around their ancestry, but sometime around 4,500 years ago they are replaced themselves in the steppe by a new people coming from Northern Europe,” says Lazaridis. Soon after, their descendants turn up in Armenia, one of the few places where many men were once and are still directly descended on their paternal line from the Yamnaya people. “It’s too good a coincidence,” says Lazaridis, “Modern Armenians are literally the last male-line descendants of the Yamnaya people, who found a new home among the inhabitants of the Armenian plateau.”
Some of the most striking results are found in the core region of the Southern Arc, Anatolia, where the large-scale data paints a rich picture of change—and lack of change—over time.
“Anatolia was home to diverse populations descended from both local hunter-gatherers and eastern populations of the Caucasus, Mesopotamia, and the Levant” says Songül Alpaslan-Roodenberg. “The people of the Marmara region and of Southeastern Anatolia, of the Black Sea, and the Aegean region all had variations of the same kinds of ancestry,” continues Alpaslan-Roodenberg. European or steppe ancestry was absent until the 1st millennium BC and even then it was not profound. Surprising the research team, a contrast existed even between the people in the Urartian Kingdom of the Eastern Anatolia region of Turkey that didn’t have steppe ancestry and their close geographical neighbors in Armenia that did.
The absence of steppe ancestry in Anatolia suggests that the dispersal of the Anatolian languages cannot be explained using the same mechanism of migrations from the steppe as all the other Indo-European languages. “There is an idea that steppe migrants entered Anatolia either from the Balkans or from the Caucasus, but if they existed at all they were a drop in a bucket. It is ancestry from the Caucasus, not the steppe, that transformed Anatolia,” says Lazaridis.
In contrast to Anatolia’s surprising impermeability to steppe migrations, the southern Caucasus was affected multiple times including prior to the Yamnaya migrations. “I did not expect to find out that the Areni 1 Chalcolithic individuals, who were recovered 15 years ago in the excavation I co-led, would derive ancestry from gene flow from the north to parts of the southern Caucasus more than 1,000 years prior to the expansion of the Yamnaya, and that this northern influence would disappear in the region before reappearing a couple of millennia later. This shows that there is a lot more to be discovered through new excavations and fieldwork in the eastern parts of Western Asia” says Ron Pinhasi
First farming societies and their interactions
The second paper -- “Ancient DNA from Mesopotamia suggests distinct Pre-Pottery and Pottery Neolithic migrations into Anatolia” -- seeks to understand how the world’s earliest Neolithic populations formed. It presents the first ancient DNA data for Pre-Pottery Neolithic farmers from the Tigris side of northern Mesopotamia—both in eastern Turkey and in northern Iraq—a prime region of the origins of agriculture. It also presents the first ancient DNA from Pre-Pottery farmers from the island of Cyprus, which witnessed the earliest maritime expansion of farmers from the eastern Mediterranean. It furthermore provides new data for early Neolithic farmers from the Northwest Zagros, along with the first data from Neolithic Armenia. By filling these gaps, the authors could study the genetic history of these societies for which archaeological research documented complex economic and cultural interactions but could not trace mating systems and interactions which do not leave visible material traces. Results reveal admixture of pre-Neolithic sources related to Anatolian, Caucasus, and Levantine hunter-gatherers, and shows that these early farming cultures formed a continuum of ancestry mirroring the geography of West Asia. The results also chart at least two pulses of migration from the Fertile Crescent heartland to the early farmers of Anatolia.
“The genetic results lend support to a scenario of a web of pan-regional contacts between early farming communities. They also provide new evidence that the Neolithic transition was a complex process that did not occur just in one core region, but across Anatolia and the Near East” says Ron Pinhasi.
“The diverse ancestry links between the Pre-Pottery Neolithic groups across Anatolia, Mesopotamia and the Levant is in agreement with archaeological research on Neolithic exchange networks especially in exotic raw materials, across long distances”, says Songül Alpaslan-Roodenberg, whose physical anthropological research focuses on the early farmers of this region.
“Paleogenetics enables us to chart the movements and admixtures of the people. Ancient DNA data, building on decades of research in physical anthropology and archaeology, is contributing to a qualitatively richer and more comprehensive picture of the origins of the first farmers”, says David Reich.
The Historic Period
The third paper -- “A genetic probe into the ancient and medieval history of Southern Europe and West Asia”-- reveals how polities of the ancient Mediterranean world preserved contrasts of ancestry since the Bronze Age but were linked by migration.
The analyses support the theory that the ancient “Mycenaeans” of Greece can be modelled as a mixture in an approximately 1:10 ratio of a Yamnaya-like steppe-derived population and a “Minoan”/Early Bronze Age-like Aegean population, on average, but with previously unknown variation clarifying social aspects of the blending process:
“The Mycenaean gene pool was not monolithic,” says Iosif Lazaridis. Steppe ancestry was common, at low levels, in both elite and non-elite individuals. Some elite men traced their paternal descent to steppe populations, but others, like the Griffin Warrior near ancient Pylos from whom we recovered DNA, did not have any steppe ancestry at all. “We have to imagine steppe migrants as a population element that became integrated, both socially and genetically, into Aegean societies, and not as a people apart that dominated them.”
The results also show that the ancestry of people who lived around Rome in the Imperial period was almost identical to that of Roman/Byzantine individuals from Anatolia in both their mean and pattern of variation, while Italians prior to the Imperial period had a very different distribution. This suggests that the Roman Empire in both its shorter-lived western part and the longer-lasting eastern part centered on Anatolia had a diverse but similar population plausibly drawn to a substantial extent from Anatolian pre-Imperial sources.
“We knew from our previous research that people who lived around Rome in the Imperial period were from various regions and that many originated from the Near East,” says Ron Pinhasi who co-led a 2019 Science study that studied ancient DNA data from Rome. “But it was a complete surprise to find such a specific and clear link to Anatolia itself, and not to other eastern parts of the Roman Empire such as the Levant.”
“This finding is another example of how archaeogenetic results can provide a missing layer of information that cannot be
Computational analysis and ancient DNA data generation for this study were supported by the John Templeton Foundation (grant 61220) (to D.R. and R.P.), and to National Institutes of Health (National Institute of General Medical Sciences grant GM100233 and National Human Genome Research Grant HG012287); a private gift from Jean-Francois Clin; the Allen Discovery Center program, a Paul G. Allen Frontiers Group advised program of the Paul G. Allen Family Foundation; and the Howard Hughes Medical Institute (to D.R.). This work was supported as part of the project “The paleogenetics of Southeastern Europeans, admixture, selection and transformations: The case of Albania,” a joint collaboration between the Albanian Institute of Archaeology (Tirana) and the Anthropology Department of the University of Vienna (principal investigators R.P., R.K., and R.R.). We thank the National Museum of Bosnia and Herzegovina and its Staff, and the project was also performed with the participation of the Austrian Archaeological Institute of the Austrian Academy of Sciences and the project on ancient Trogir in Croatia co-led by Martin Steskal. The project acknowledges support from the Ministry of Science and Innovation of the Spanish Government (RYC2019-027909-I/AEI/10.13039/501100011033) and Ikerbasque-Basque Foundation of Science grants (I.O.). The archaeological work was supported by the NOMIS Foundation (D.B.); the European Research Council (ERC Starting Grant Project HIDDEN FOODS 639286 to E.Cr.); the Romanian Ministry of Research, Innovation, and Digitization (CNCS, CNFIS, CCCDI – UEFISCDI project numbers 351PED PN-III-P2-2.1- PED-2019-4171 and CNFIS-FDI-2021-0405 D6/ 2021 within PNCDI III to C.L.); the Face to Face: Meet an Ancient Cypriot project (FF-MAC project INTEGRATED/0609/29); the BioMERA project (Platform for Biosciences and Human Health in Cyprus: MicroCT and Synchrotron Radiation Enabled Analyses; grant INFRASTRUCTURES/1216/09) cofinanced by the European Regional Development Fund and the Republic of Cyprus through the Research and Innovation Foundation (KOL); the Hungarian Research, Development and Innovation Office (grant FK128013 to T.H., T.Sz., and K.K.); the Hungarian Academy of Science (Bolyai Scholarship to T.H.); the Croatian Science Foundation (grant HRZZ IP-2016-06-1450 to M.N., I.J., and J.B. and grant NCN 2015/17/B/HS3/01327 to P.W.); and the Bursa Uludağ University (Turkey) General Research Project (grant SGA-2021-389, project title “Early Christian martyriums in the light of the Basilica Church of the Lake of Iznik,” to M.Şa.).
Contacts:
Ron Pinhasi: Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria.
Email: ron.pinhasi@univie.ac.at
mobile: +43 664 8176207
Songül Alpaslan-Roodenberg: Department of Genetics, Harvard Medical School, Boston, USA, and Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria.
Email: msglalpaslan@gmail.com
Iosif Lazaridis: Department of Genetics, Harvard Medical School, Boston, USA.
Email: lazaridis@genetics.med.harvard.edu
David Reich: Department of Genetics, Harvard Medical School, Boston, USA.
