genomes Scythians

Ancient Genomes Trace the Origin and Decline of the Scythians

Ancient Genomes Trace the Origin and Decline of the Scythians

Generally thought of as fierce horse-warriors, the Scythians were a multitude of Iron Age cultures who ruled the Eurasian steppe, playing a major role in Eurasian history. A new study published in Science Advances analyzes genome-wide data for 111 ancient individuals spanning the Central Asian Steppe from the first millennia BCE and CE. The results reveal new insights into the genetic events associated with the origins, development and decline of the steppe’s legendary Scythians.

Because of their interactions and conflicts with the major contemporaneous civilizations of Eurasia, the Scythians enjoy a legendary status in historiography and popular culture. The Scythians had major influences on the cultures of their powerful neighbors, spreading new technologies such as saddles and other improvements for horse riding. The ancient Greek, Roman, Persian and Chinese empires all left a multitude of sources describing, from their perspectives, the customs and practices of the feared horse warriors that came from the interior lands of Eurasia.

An aerial view of Hun-Xianbi culture burials. Both horses and warriors can be identified. Credits: © Zainolla Samashev

Still, despite evidence from external sources, little is known about Scythian history. Without a written language or direct sources, the language or languages they spoke, where they came from and the extent to which the various cultures spread across such a huge area were in fact related to one another, remain unclear.

The Iron Age transition and the formation of the genetic profile of the Scythians

A new study published in Science Advances by an international team of geneticists, anthropologists and archeologists lead by scientists from the Archaeogenetics Department of the Max Planck Institute for the Science of Human History in Jena, Germany, helps illuminate the history of the Scythians with 111 ancient genomes from key Scythian and non-Scythian archaeological cultures of the Central Asian steppe. The results of this study reveal that substantial genetic turnovers were associated with the decline of the long-lasting Bronze Age sedentary groups and the rise of Scythian nomad cultures in the Iron Age. Their findings show that, following the relatively homogenous ancestry of the late Bronze Age herders, at the turn of the first millennium BCE, influxes from the east, west and south into the steppe formed new admixed gene pools.

Mound 4 of the Eleke Sazy necropolis in eastern Kazakhstan. Credits: © Zainolla Samashev

The diverse peoples of the Central Asian Steppe

The study goes even further, identifying at least two main sources of origin for the nomadic Iron Age groups. An eastern source likely originated from populations in the Altai Mountains that, during the course of the Iron Age, spread west and south, admixing as they moved. These genetic results match with the timing and locations found in the archeological record and suggest an expansion of populations from the Altai area, where the earliest Scythian burials are found, connecting different renowned cultures such as the Saka, the Tasmola and the Pazyryk found in southern, central and eastern Kazakhstan respectively. Surprisingly, the groups located in the western Ural Mountains descend from a second separate, but simultaneous source. Contrary to the eastern case, this western gene pool, characteristic of the early Sauromatian-Sarmatian cultures, remained largely consistent through the westward spread of the Sarmatian cultures from the Urals into the Pontic-Caspian steppe.

The decline of the Scythian cultures associated with new genetic turnovers

The study also covers the transition period after the Iron Age, revealing new genetic turnovers and admixture events. These events intensified at the turn of the first millennium CE, concurrent with the decline and then disappearance of the Scythian cultures in the Central Steppe. In this case, the new far eastern Eurasian influx is plausibly associated with the spread of the nomad empires of the Eastern steppe in the first centuries CE, such as the Xiongnu and Xianbei confederations, as well as minor influxes from Iranian sources likely linked to the expansion of Persian-related civilization from the south.

Although many of the open questions on the history of the Scythians cannot be solved by ancient DNA alone, this study demonstrates how much the populations of Eurasia have changed and intermixed through time. Future studies should continue to explore the dynamics of these trans-Eurasian connections by covering different periods and geographic regions, revealing the history of connections between west, central and east Eurasia in the remote past and their genetic legacy in present day Eurasian populations.

The burial of a social elite known as 'Golden Man' from the Eleke Sazy necropolis. Credits: © Zainolla Samashev

Press release from Max Planck Institute for the Science of Human History in Jena on the new study that helps illuminate the history of the Scythians with 111 ancient genomes from archaeological cultures of the Central Asian steppe.


Dramatic change in ancient nomad diets coincides with expansion of networks across Eurasia

Dramatic change in ancient nomad diets coincides with expansion of networks across Eurasia

nomad pastoralists diets
Map of millet and wheat/barley consumption over time: a) 1000-500 cal BC, b) 500-200 cal BC, and c) 200 BC-AD 400. Credit: Map of millet and wheat/barley consumption over time: a) 1000-500 cal BC, b) 500-200 cal BC, and c) 200 BC-AD 400

A meta-analysis of dietary information recorded in the bones of ancient animals and humans recovered from sites scattered across the Eurasian steppe, from the Caucasus region to Mongolia, demonstrates that pastoralists spread domesticated crops across the steppe through their trade and social networks. Researchers from Kiel University sifted through previously published stable isotopic data and applied new quantitative analyses that calibrate human dietary intake against environmental inputs. The results have allowed them to better isolate the timing of the incorporation of agricultural products into the diets of pastoral nomads and, crucially, link burgeoning socio-political networks to this dietary transformation.

Through a big data project that explored over a thousand stable isotope data points, researchers were able to find evidence for an early transition to agriculture - based on dietary intake across Eurasia. "Our understanding of the pace of crop transmission across the Eurasian steppe has been surprisingly unclear due in part to a focus on the excavation of cemeteries, rather than settlements where people threw out their food," says Alicia Ventresca Miller, lead author, formerly of Kiel University and currently at the Max Planck Institute for the Science of Human History. "Even when settlement sites are excavated, the preservation of carbonized seed remains is often poor. This is what makes stable isotope analyses of human remains from this region so valuable - it provides direct insights into the dietary dynamics of ancient pastoralists who inhabited diverse environments."

Millet spreads across the Eurasian steppe

Millet, originally domesticated in China, appears to have been occasionally consumed at low levels by pastoralists inhabiting the far-flung regions of Siberia and southeastern Kazakhstan, possibly as early as the late third millennium. This initial uptake of millet coincided with the expansion of trans-regional networks across the steppe, when objects and ideas were first regularly exchanged over long-distances.

However, it was not until a thousand years later that millet became a regular feature of pastoralist diets. This timing coincides with the intensification of complex political structures at the transition to the Iron Age. Burgeoning socio-political confederations drove a marked increase in the exchange of costly prestige goods, which strengthened political networks - and facilitated the transfer of cultigens.

Wheat and Barley in the Trans-Urals

Despite taking part in these political networks, groups in the Trans-Urals invested in wheat and barley farming rather than millet. A dietary focus on wheat and barley may have been due to different farming techniques, greater water availability, or a higher value on these cultigens. "Our research suggests that cultigens were converted from a rare luxury during the Bronze Age to a medium demarcating elite participation in political networks during the Iron Age," states Cheryl Makarewicz of Kiel University.

Regional variation in millet consumption

While herding of livestock was widespread, not all regions adopted millet. In southwest Siberia, dietary intake was focused on pastoral animal products and locally available wild plants and fish. In contrast, the delayed adoption of millet by populations in Mongolia during the Late Iron Age coincides with the rise of the Xiongnu nomadic empire. "This is particularly interesting because it suggests that communities in Mongolia and Siberia opted out of the transition to millet agriculture, while continuing to engage with neighboring groups," explains Ventresca Miller.

This study shows the great potential of using the available isotope record to provide evidence for human dietary intake in areas where paleobotany is understudied. Further research should clarify the exact type of grains, for example broomcorn or foxtail millet, were fundamental to the shift in dietary intake and how networks of exchange linked different regions.

###

Original publication:

Ventresca Miller and Makarewicz, Intensification in pastoralist cereal use coincides with the expansion of trans-regional networks in the Eurasian Steppe, Scientific Reports (2019). DOI: https://doi.org/10.1038/s41598-018-35758-w

 

Press release from Kiel University / Christian-Albrechts-Universität zu Kiel