The Yamnaya Steppe Herders from Russia

Extended Data Figure 2

By using a large number of outgroup populations we can fit the admixture coefficients αi and estimate mixture proportions (Supplementary Information section 9, Extended Data Fig. 2). Using 15 outgroups from Africa, Asia, Oceania and the Americas, we obtain good fits as assessed by a formal test (Supplementary Information section 10), and estimate that the Middle Neolithic populations of Germany and Spain have ∼18–34% more WHG-related ancestry than Early Neolithic populations and that the Late Neolithic and Early Bronze Age populations of Germany have ∼22–39% more EHG-related ancestry than the Middle Neolithic ones (Supplementary Information section 9). If we model them as mixtures of Yamnaya-related and Middle Neolithic populations, the inferred degree of population turnover is doubled to 48–80% (Supplementary Information sections 9 and 10). To distinguish whether a Yamnaya or an EHG source fits the data better, we added ancient samples as outgroups (Supplementary Information section 9).

Adding any Early or Middle Neolithic farmer results in EHG-related genetic input into Late Neolithic populations being a poor fit to the data (Supplementary Information section 9); thus, Late Neolithic populations have ancestry that cannot be explained by a mixture of EHG and Middle Neolithic. When using Yamnaya instead of EHG, however, we obtain a good fit (Supplementary Information sections 9 and 10). These results can be explained if the new genetic material that arrived in Germany was a composite of two elements: EHG and a type of Near Eastern ancestry different from that which was introduced by early farmers (also suggested by PCA and ADMIXTURE; Fig. 2, Supplementary Information sections 5 and 6). We estimate that these two elements each contributed about half the ancestry of the Yamnaya (Supplementary Information sections 6 and 9), explaining why the population turnover inferred using Yamnaya as a source is about twice as high compared to the undiluted EHG. The estimate of Yamnaya related ancestry in the Corded Ware is consistent when using either present populations or ancient Europeans as outgroups (Supplementary Information sections 9 and 10), and is 73.1±2.2% when both sets are combined (Supplementary Information section 10). The best proxies for ANE ancestry in Europe4 were initially Native Americans12,22, and then the Siberian MA1 (ref. 6), but both are geographically and temporally too remote for what appears to be a recent migration into Europe4. We can now add three new pieces to the puzzle of how ANE ancestry was transmitted to Europe: first by the EHG, then the Yamnaya formed by mixture between EHG and a Near Eastern related population, and then the Corded Ware who were formed by a mixture of the Yamnaya with Middle Neolithic Europeans. We caution that the sampled Yamnaya individuals from Samara might not be directly ancestral to Corded Ware individuals from Germany. It is possible that a more western Yamnaya population, or an earlier (pre-Yamnaya) steppe population may have migrated into central Europe, and future work may uncover more missing links in the chain of transmission of steppe ancestry. By extending our model to a three-way mixture of WHG, Early Neolithic and Yamnaya, we estimate that the ancestry of the Corded Ware was 79% Yamnaya-like, 4% WHG, and 17% Early Neolithic (Fig. 3). A small contribution of the first farmers is also consistent with uniparentally inherited DNA: for example, mitochondrial DNA haplogroup N1a and Y chromosome haplogroup G2a, common in early central European farmers14,23, almost disappear during the Late Neolithic and Bronze Age, when they are largely replaced by Y haplogroups R1a and R1b (Supplementary Information section 4)and mtDNA haplogroups I,T1,U2,U4, U5a,W, and subtypes of H14,23,24 (Supplementary Information section 2). The uniparental data not only confirm a link to the steppe populations but also suggest that both sexes participated in the migrations (Supplementary Information sections 2 and 4 and Extended Data Table 2). The magnitude of the population turnover that occurred becomes even more evident if one considers the fact that the steppe migrants may well have mixed with eastern European agriculturalists on their way to central Europe. Thus, we cannot exclude a scenario in which the Corded Ware arriving in today's Germany had no ancestry at all from local populations.


Figure 3
Admixture proportions

Our results support a view of European pre-history punctuated by two major migrations: first, the arrival of the first farmers during the Early Neolithic from the Near East, and second, the arrival of Yamnaya pastoralists during the Late Neolithic from the steppe. Our data further show that both migrations were followed by resurgences of the previous inhabitants: first, during the Middle Neolithic, when hunter-gatherer ancestry rose again after its Early Neolithic decline, and then between the Late Neolithic and the present, when farmer and hunter-gatherer ancestry rose after its Late Neolithic decline. This second resurgence must have started during the Late Neolithic/Bronze Age period itself, as the Bell Beaker and Unetice groups had reduced Yamnaya ancestry compared to the earlier Corded Ware, and comparable levels to that in some present-day Europeans (Fig. 3). Today, Yamnaya related ancestry is lower in southern Europe and higher in northern Europe, and all European populations can be modelled as a three-way mixture of WHG, Early Neolithic, and Yamnaya, whereas some outlier populations show evidence for additional admixture with populations from Siberia and the Near East (Extended Data Fig. 3, Supplementary Information section 9). Further data are needed to determine whether the steppe ancestry arrived in southern Europe at the time of the Late Neolithic/Bronze Age, or is due to migrations in later times from northern Europe25,26. Our results provide new data relevant to debates on the origin and expansion of Indo-European languages in Europe (Supplementary Information section 11).


Geographic distribution of archaeological cultures and graphic illustration of proposed population movements / turnovers discussed in the main text (symbols of samples are identical to Figure 1)

Although the findings from ancient DNA are silent on the question of the languages spoken by preliterate populations, they do carry evidence about processes of migration which are invoked by theories on Indo-European language dispersals. Such theories make predictions about movements of people to account for the spread of languages and material culture (Extended Data Fig. 4). The technology of ancient DNA makes it possible to reject or confirm the proposed migratory movements, as well as to identify new movements that were not previously known. The best argument for the ‘Anatolian hypothesis’27 that Indo-European languages arrived in Europe from Anatolia ∼8,500 years ago is that major language replacements are thought to require major migrations, and that after the Early Neolithic when farmers established themselves in Europe, the population base was likely to have been so large that later migrations would not have made much of an impact27,28. However, our study shows that a later major turnover did occur, and that steppe migrants replaced ∼75% of the ancestry of central Europeans. An alternative theory is the ‘steppe hypothesis’, which proposes that early Indo-European speakers were pastoralists of the grasslands north of the Black and Caspian Seas, and that their languages spread into Europe after the invention of wheeled vehicles9. Our results make a compelling case for the steppe as a source of at least some of the Indo-European languages in Europe by documenting a massive migration ∼4,500 years ago associated with the Yamnaya and Corded Ware cultures, which are identified by proponents of the steppe hypothesis as vectors for the spread of Indo-European languages into Europe. These results challenge the Anatolian hypothesis by showing that not all Indo-European languages in Europe can plausibly derive from the first farmer migrations thousands of years earlier (Supplementary Information section 11). We caution that the location of the proto-Indo-European9,27,29,30 homeland that also gave rise to the Indo-European languages of Asia, as well as the Indo-European languages of southeastern Europe, cannot be determined from the data reported here (Supplementary Information section 11). Studying the mixture in the Yamnaya themselves, and understanding the genetic relationships among a broader set of ancient and present-day Indo- European speakers, may lead to new insight about the shared homeland.

Nature. 2015 Jun 11; 522(7555): 207–211.

Figure 2; Structure and population change in European
populations with mainly hunter-gatherer ancestry.


An alternative hypothesis is that the ultimate homeland of Proto-Indo European languages was in the Caucasus or in Iran. In this scenario, westward movement contributed to the dispersal of Anatolian languages, and northward movement and mixture with EHG was responsible for the formation of the population associated with the Yamnaya complex. These steppe pastoralists plausibly spoke a “Late Proto-Indo European” language that is ancestral to many of the non-Anatolian branches of the Indo-European language family.



On the other hand, our data could still be consistent with the Steppe-Balkans-Anatolia route hypothesis model, albeit with constraints. It remains possible that populations dating to around 1600 BCE in the regions where the Indo-European Luwian, Hittite and Palaic languages were spoken did have European hunter-gatherer ancestry. However, our results would require that such ancestry was not ubiquitous in Bronze Age Anatolia, and was perhaps tightly linked to Indo-European speaking groups.



We predict that additional insight about the genetic origins of the potential speakers of early Indo-European languages will be obtained when ancient DNA data become available from additional sites in this key period in Anatolia and the Caucasus.