“Ancient genomes from modern Ukraine and Russia reveal the origins of the Yamna people, pastoralists who migrated from the Eurasian steppe to Europe 5,000 years ago, spreading their ancestry, culture and, probably, language.
Around 5,000 years ago, pastoralists of the Yamna, or Yamnaya, culture from the Pontic–Caspian steppe, which spans eastern Europe and central Asia north of the Black and Caspian seas, rode west into Europe and transformed the cultural and genetic landscape of the continent permanently1. Previous studies1,2 have proposed that these people also brought with them Indo-European languages, now spoken in most of Europe. Writing in Nature, Lazaridis et al.3 shed light on the demographic processes that shaped pre-Yamna populations in the Pontic–Caspian steppe and Nikitin et al.4 reveal the genetic origins of the Yamna.
The Neolithic period (or New Stone Age, spanning roughly 10000–5000 bc) was a time of enormous cultural change and variation in the Pontic–Caspian steppe. Hunter-gatherer cultures persisted in the area while new cultures appeared, bringing along practices such as pastoralism, dairying and agriculture. The transition continued with the development of copper alloys1 during the Eneolithic period (or Copper Age, spanning 5000–3000 bc), which preceded the Bronze Age.
The movement and coexistence of groups with distinct genetic backgrounds resulted in the groups genetically mixing (admixing) with each other. Evidence of this can be seen in Ukrainian Neolithic hunter-gatherers with ancestries related to populations from the Caucasus (a mountainous region between the Black and Caspian seas)5 and in farmers of the Trypillia, Cernavodă and Usatove cultures, who had hunter-gatherer or steppe-related ancestries (or both)6–8.
People of the Yamna culture were nomadic pastoralists who used horses and wheeled carts for herding and who buried their dead in large mounds called kurgans1. In 2015, the first Yamna genomes were reported in two landmark publications9,10. The studies demonstrated that, starting with a culture known as Corded Ware, which existed between the Late Neolithic period and the Bronze Age, almost all European populations carried a large proportion of Yamna-related ancestry. It has since been shown that the Yamna people had some ancestry from early farmers of Anatolia, a region south of the Black Sea11 — but the specifics of the Yamna people’s origin have remained elusive.
Lazaridis et al. and Nikitin et al. present genomic data for 367 individuals from the Pontic–Caspian steppe and surrounding areas, doubling the number of available genomes from the Eneolithic period and almost quadrupling those of Yamna people. The data set includes numerous previously unsampled cultural groups and locations. The studies challenge simplistic narratives of migration and replacement. They depict a dynamic process of interaction and integration, in which new cultural practices emerged from the blending of diverse groups. The evidence also highlights the resilience and adaptability of steppe populations, who navigated considerable environmental and social changes over thousands of years.
The authors propose that the Eneolithic population admixtures that led to the formation of the Yamna group can be modelled using three genetic ‘clines’ — gradients in the genetic make-up, often occurring across a geographical region. The first (the Dnipro cline) is associated with the Dnipro River, which flows into the Black Sea; the second (the Volga cline) with the Volga River, which flows into the Caspian Sea; and the third, the Caucasus–lower Volga cline, with the lower part of the Volga River and the Caucasus. These clusters in turn interacted with European hunter-gatherers and (western) European hunter-gatherer–farmers. This model captures the temporal and spatial dynamics of genetic exchanges in the steppe region.
Explanation:
Origins of the Yamna culture. To identify the genetic and geographical origins of the Yamna people, representing an influential culture that is thought to have brought Indo-European languages to Europe around 5,000 years ago, Lazaridis et al.3 and Nikitin et al.4 analysed ancient DNA from archaeological sites in the Pontic–Caspian steppe (spanning present-day Russia and Ukraine) and surrounding areas. They found that pre-Yamna populations living in this region during the Neolithic and Eneolithic periods (10000–3000 bc) belonged to three genetic gradients (clines) that are correlated with geographical locations: one along the Volga River, one along the Dnipro River and one that spans the lower Volga and the Caucasus mountains. The authors show that the Yamna people originated from the lower-Volga end of the Dnipro cline genetically and potentially from the lower Dnipro region geographically, as represented by the Mykhailivka settlement in Ukraine. The subsequent spread of uniform Yamna ancestry over a large area is indicative of a rapid expansion in the late Eneolithic period and early Bronze Age.
The Volga cline, for example, shows evidence of shifts in admixture patterns over time, reflecting the long-term interaction between local foragers and incoming populations. One particularly intriguing discovery is the low-level presence of early European farmer ancestry in Ukrainian Neolithic hunter-gatherers in addition to the previously identified5 Caucasus-related ancestry, providing insights into interactions in this region.
Furthermore, Nikitin and colleagues clarify admixtures in farming groups, showing that the steppe-related admixture in Trypillia and Cernavodă individuals comes from the lower Volga, whereas the population contributing to the Usatove gene pool must have had slightly more Caucasus-related ancestry. This again points to complex interaction networks between the region north of the Black Sea and areas adjacent to it.
The birth of Bronze Age pastoralism where Europe meets Asia
The large number of Yamna-related genomes from a wide area — from Bulgaria to the Altai region of southern Siberia — reveals an astonishing degree of genetic uniformity, especially in the early stages of the spread of the culture, suggesting the rapid dispersal of people carrying this ancestry. The Yamna genomes fall on the Dnipro cline, revealing a degree of continuity from Ukrainian Neolithic hunter-gatherers to people of the Eneolithic Serednii Stih culture to the Yamna people. This, together with the fact that the earliest sampled Yamna-related individual is from the archaeological site of Mykhailivka in modern Ukraine, is consistent with the lower Dnipro being the potential region where the Yamna culture emerged.
Although these studies mark a substantial advance, several questions remain. Their focus is on populations from the steppe, leaving gaps in the understanding of contemporaneous groups in adjacent regions. Furthermore, the link between genetic admixture and cultural change requires further exploration through the synthesis of data and expertise of researchers who study distinct aspects of human history. For example, how did the social and economic structures of the Yamna people influence their genetic legacy? Similarly, the presence of early European farmer ancestry in Ukrainian hunter-gatherers raises questions about the westward contacts of this group.
Even though the social structure of a population can leave detectable traces in its genetic diversity patterns, drawing definitive conclusions about the language spoken by a group on the basis of only genetic data remains impossible. Although it is highly plausible that the expansion of the Yamna people played a key part in the spread of the Indo-European language family, it is important to approach this conclusion with some caution.
Future research could explore the role of environmental factors, such as climate change and potential pathogen–host co-evolutionary cycles, in shaping the migrations and interactions that have been documented in these studies. Expanding the genetic data set to include more individuals from under-represented regions, such as people from the Balkans in southeastern Europe, the Caucasus foothills and northern parts of the East European Plain (which extends north of the Pontic–Caspian steppe), would also refine researchers’ understanding of early population dynamics.” [1]
1. Nature 639, 46-47 (2025) By Lehti Saag & Mait Metspalu
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