Basal Eurasian is a proposed lineage of anatomically modern humans with reduced, or zero, Neanderthal admixture (ancestry) compared to other ancient non-Africans. Basal Eurasians represent a sister lineage to other Eurasians and may have originated from the Southern Middle East, specifically the Arabian Peninsula, or North Africa, and are said to have contributed ancestry to various West Eurasian, South Asian, and Central Asian as well as African groups. This Basal Eurasian component is also proposed to explain the lower archaic admixture among modern West Eurasians compared with East Eurasians, although alternatives without the need of such Basal admixture exist as well. [1] Basal Eurasian ancestry had likely admixed into West Eurasian groups present in West Asia as early as 26,000 years ago, prior to the Last Glacial Maximum, with this ancestry being subsequently spread by later migrations, such as those of the Anatolian Neolithic Farmers into Europe during the Holocene. [2]
A study by Lazaridis et al. in 2014 demonstrated that modern Europeans can be modelled as an admixture of three ancestral populations; Ancient North Eurasians (ANE), Western Hunter-Gatherers (WHG), and Early European Farmers (EEF). [3] This same study also showed that EEFs harbour ancestry from a hypothetical non-African 'ghost' population which the authors name 'Basal Eurasians'. This group, who have not yet been sampled from ancient remains, are thought to have diverged from all non-African populations c. 60,000 to 100,000 years ago, before non-Africans admixed with Neanderthals (c. 50,000 to 60,000 years ago) and diversified from each other. A second study by Lazaridis et al. in 2016 found that populations with higher levels of Basal Eurasian ancestry have lower levels of Neanderthal ancestry, which suggests that Basal Eurasians had lower levels of Neanderthal ancestry compared with other non-Africans. Another study by Ferreira et al. in 2021 suggested that Basal Eurasians diverged from other Eurasians between 50,000 and 60,000 years ago, and lived somewhere in the Arabian peninsula, specifically the Persian Gulf region, shortly before proper Eurasians admixed with a Neanderthal population in a region stretching from the Levant to northern Iran. [4] [5] [6] [7] [8] Vallini et al. 2024 argues that the Basal Eurasian lineage diverged from other Eurasians soon after the Out-of-Africa migration, and subsequently became isolated, until it started to mix with other populations in the Middle East since around 25,000 years ago. These different Middle Eastern populations would later spread Basal Eurasian ancestry via the Neolithic Revolution to all of Western Eurasia. [9]
In modern populations, Neanderthal ancestry is around 10% to 20% lower in West Eurasians than East Eurasians, with intermediate levels found in South and Central Asian populations. Although a scenario involving multiple admixture events between modern humans and Neanderthals is an alternative possibility, the most likely explanation for this is that Neanderthal ancestry in West Eurasians and South and Central Asians was diluted by admixture with Basal Eurasian groups. [5]
The earliest evidence of Basal Eurasian ancestry is found in individuals from Dzudzuana Cave in Georgia dating to 26,000 years ago which have around 30% Basal Eurasian ancestry, with the rest being West Eurasian. [2]
Basal Eurasians may have originated in a region stretching from North Africa to the Middle East, before admixing with West-Eurasian populations. [4] [5] [6] [7] [8] North Africa has been described as a strong candidate for the location of the emergence of Basal Eurasians by Loosdrecht et al. in 2018. [10]
Ferreira et al. in 2021 argued for a point of origin for Basal Eurasians into the Middle East, specifically in the Persian Gulf region on the Arab peninsula. As Basal Eurasians had low levels of Neanderthal ancestry, genetic and archaeological evidence for interactions between modern humans and Neanderthals may allow certain areas, such as the Levant, to be ruled out as possible sources for Basal Eurasians. In other areas, such as southern Southwest Asia, there is currently no evidence for an overlap between modern human and Neanderthal populations. [7] Vallini et al. 2024 suggests a homeland for Basal Eurasians in the Arabian Peninsula, with a 'Common Eurasian Hub' in the Iranian Plateau, where they diverged into 'Ancient West Eurasians' and 'Ancient East Eurasians'. [9]
An estimation for Holocene-era Near Easterners (e.g., Mesolithic Caucasus hunter-gatherers, Mesolithic and Neolithic Iranians, and Natufians) suggests that they formed from a combination of Basal Eurasian ancestry, and Western Hunter-Gatherer-related (WHG) and or Ancient North Eurasians-related (ANE) ancestries respectively. [10] The Mesolithic and Neolithic Iranian lineage is inferred to derived between 38–48% ancestry from Basal Eurasians respectively, with the remainder ancestry being made up by Ancient North Eurasian or Eastern Hunter-Gatherer (EHG) like ancestry, while Natufians derived a mean average of 50% Basal and 50% 'unknown hunter-gatherer' ancestry being closer to Western Hunter-Gatherers (WHG). [11] [12] [13] [14] Alternatively, Mesolithic and Neolithic Iranians derive most of their ancestry from a deep West Eurasian source (WEC2; c. 72%) with c. 18% Basal Eurasian and c. 10% Ancient East Eurasian admixture. [15] It has been found that the "models of genetic history of West Asian human populations who are modeled as a mixture of ‘basal Eurasians’ and West European hunter–gatherers" is in agreement with the genomic data on 'East Mediterranean Dogs', who "are modeled as a mixture of a basal branch (splitting deeper than the divergence of the Asian and European dogs) and West European dogs". [16]
The Ancient North African Iberomaurusian (Taforalt) individuals were found to have harbored ~65% West Eurasian-like ancestry and considered likely direct descendants of such "Basal Eurasian" population. However they were shown to be genetically closer to Holocene-era Iranians and Levantine populations, which already harbored increased archaic (Neanderthal) admixture. [10]
Early European Farmers (EEFs), who had some Western European Hunter-Gatherer-related ancestry and originated in the Near East, also derive approximately 30% (to up to 44%) of their ancestry from this hypothetical Basal Eurasian lineage. [3] [17] An Upper Paleolithic specimen from Kotias Klde cave in the Caucasus (Caucasus_25,000BP) had around 24% Basal Eurasian and 76% Upper Paleolithic European ancestry. [14]
Among modern populations, Basal-like ancestry peaks among Arabs (such as Qataris) at c. 45%, and among Iranian populations at c. 35%, and is also found in significant amounts among modern Northern Africans, in accordance with the high affinity towards the 'Arabian branch' of Eurasian diversity, which expanded into Northern and Northeastern Africa between 30 and 15 thousand years ago. Modern populations of the Levant derive between 35-38% ancestry from Basal Eurasians, modern Anatolians and populations from the Caucasus derive between 25-30% ancestry from Basal Eurasians, and modern Europeans derive around or less than 20% ancestry from Basal Eurasians. [7] Modern Bedouins and Yemenis are considered to represent direct descendants of the Basal Eurasians, carrying the highest amount of indigenous 'Arabian ancestry', and being basal to all modern Eurasian populations without displaying higher 'African-associated' admixture, and thus "are among the best genetic representatives of the autochthonous population on the Arabian Peninsula". [18]
Natufian culture is a Late Epipaleolithic archaeological culture of the Neolithic prehistoric Levant in Western Asia, dating to around 15,000 to 11,500 years ago. The culture was unusual in that it supported a sedentary or semi-sedentary population even before the introduction of agriculture. Natufian communities may be the ancestors of the builders of the first Neolithic settlements of the region, which may have been the earliest in the world. Some evidence suggests deliberate cultivation of cereals, specifically rye, by the Natufian culture at Tell Abu Hureyra, the site of earliest evidence of agriculture in the world. The world's oldest known evidence of the production of bread-like foodstuff has been found at Shubayqa 1, a 14,400-year-old site in Jordan's northeastern desert, 4,000 years before the emergence of agriculture in Southwest Asia. In addition, the oldest known evidence of possible beer-brewing, dating to approximately 13,000 BC, was found in Raqefet Cave on Mount Carmel, although the beer-related residues may simply be a result of a spontaneous fermentation.
The Yamnaya culture or the Yamna culture, also known as the Pit Grave culture or Ochre Grave culture, is a late Copper Age to early Bronze Age archaeological culture of the region between the Southern Bug, Dniester, and Ural rivers, dating to 3300–2600 BC. It was discovered by Vasily Gorodtsov following his archaeological excavations near the Donets River in 1901–1903. Its name derives from its characteristic burial tradition: Я́мная is a Russian adjective that means 'related to pits ', as these people used to bury their dead in tumuli (kurgans) containing simple pit chambers. Research in recent years has found that Mikhaylovka, in lower Dnieper river, Ukraine, formed the Core Yamnaya culture.
Pre-Pottery Neolithic B (PPNB) is part of the Pre-Pottery Neolithic, a Neolithic culture centered in upper Mesopotamia and the Levant, dating to c. 10,800 – c. 8,500 years ago, that is, 8800–6500 BC. It was typed by British archaeologist Kathleen Kenyon during her archaeological excavations at Jericho in the West Bank, territory of Palestine.
The Sredny Stog culture or Serednii Stih culture is a pre-Kurgan archaeological culture from the mid. 5th – mid. 4th millennia BC. It is named after the Dnieper river islet of today's Serednii Stih, Ukraine, where it was first located.
The genetic history of Europe includes information around the formation, ethnogenesis, and other DNA-specific information about populations indigenous, or living in Europe.
Ganj Dareh is a Neolithic settlement in western Iran. It is located in the Harsin County in east of Kermanshah Province, in the central Zagros Mountains.
The genetic history of the Middle East is the subject of research within the fields of human population genomics, archaeogenetics and Middle Eastern studies. Researchers use Y-DNA, mtDNA, and other autosomal DNA tests to identify the genetic history of ancient and modern populations of Egypt, Persia, Mesopotamia, Anatolia, Arabia, the Levant, and other areas.
Mechta-Afalou, also known as Mechtoid or Paleo-Berber, are a population that inhabited parts of North Africa during the late Paleolithic and Mesolithic. They are associated with the Iberomaurusian archaeological culture.
The Iberomaurusian is a backed bladelet lithic industry found near the coasts of Morocco, Algeria, and Tunisia. It is also known from a single major site in Libya, the Haua Fteah, where the industry is locally known as the Eastern Oranian. The Iberomaurusian seems to have appeared around the time of the Last Glacial Maximum (LGM), somewhere between c. 25,000 and 23,000 cal BP. It would have lasted until the early Holocene c. 11,000 cal BP.
Interbreeding between archaic and modern humans occurred during the Middle Paleolithic and early Upper Paleolithic. The interbreeding happened in several independent events that included Neanderthals and Denisovans, as well as several unidentified hominins.
Taforalt, or Grotte des Pigeons, is a cave in the province of Berkane, Aït Iznasen region, Morocco, possibly the oldest cemetery in North Africa. It contained at least 34 Iberomaurusian adolescent and adult human skeletons, as well as younger ones, from the Upper Palaeolithic between 15,100 and 14,000 calendar years ago. There is archaeological evidence for Iberomaurusian occupation at the site between 23,200 and 12,600 calendar years ago, as well as evidence for Aterian occupation as old as 85,000 years.
The term Eurasian backflow, or Eurasian back-migrations, has been used to describe several pre-Neolithic and Neolithic migration events of humans from western Eurasia back to Africa.
In archaeogenetics, the term Ancient North Eurasian (ANE) is the name given to an ancestral component that represents the lineage of the people of the Mal'ta–Buret' culture and populations closely related to them, such as the Upper Paleolithic individuals from Afontova Gora in Siberia. Genetic studies also revealed that the ANE are closely related to the remains of the preceding Yana culture, which were named Ancient North Siberians (ANS). Ancient North Eurasians are predominantly of West Eurasian ancestry who arrived in Siberia via the "northern route", but also derive a significant amount of their ancestry from an East Eurasian source, having arrived to Siberia via the "southern route".
Early European Farmers (EEF) were a group of the Anatolian Neolithic Farmers (ANF) who brought agriculture to Europe and Northwest Africa. The Anatolian Neolithic Farmers were an ancestral component, first identified in farmers from Anatolia (also known as Asia Minor) in the Neolithic, and outside in Europe and Northwest Africa, they also existed in Iranian Plateau, South Caucasus, Mesopotamia and Levant. Although the spread of agriculture from the Middle East to Europe has long been recognised through archaeology, it is only recent advances in archaeogenetics that have confirmed that this spread was strongly correlated with a migration of these farmers, and was not just a cultural exchange.
In archaeogenetics, western hunter-gatherer is a distinct ancestral component of modern Europeans, representing descent from a population of Mesolithic hunter-gatherers who scattered over western, southern and central Europe, from the British Isles in the west to the Carpathians in the east, following the retreat of the ice sheet of the Last Glacial Maximum. It is closely associated and sometimes considered synonymous with the concept of the Villabruna cluster, named after Ripari Villabruna cave in Italy, known from the terminal Pleistocene of Europe, which is largely ancestral to later WHG populations.
Caucasus hunter-gatherer (CHG), also called Satsurblia cluster, is an anatomically modern human genetic lineage, first identified in a 2015 study, based on the population genetics of several modern Western Eurasian populations.
In archaeogenetics, eastern hunter-gatherer (EHG), sometimes east European hunter-gatherer or eastern European hunter-gatherer, is a distinct ancestral component that represents Mesolithic hunter-gatherers of Eastern Europe.
In archaeogenetics, the term Scandinavian hunter-gatherer (SHG) is the name given to a distinct ancestral component that represents descent from Mesolithic hunter-gatherers of Scandinavia. Genetic studies suggest that the SHGs were a mix of western hunter-gatherers (WHGs) initially populating Scandinavia from the south during the Holocene, and eastern hunter-gatherers (EHGs), who later entered Scandinavia from the north along the Norwegian coast. During the Neolithic, they admixed further with Early European Farmers (EEFs) and Western Steppe Herders (WSHs). Genetic continuity has been detected between the SHGs and members of the Pitted Ware culture (PWC), and to a certain degree, between SHGs and modern northern Europeans. The Sámi, on the other hand, have been found to be completely unrelated to the PWC.
In archaeogenetics, the term Western Steppe Herders (WSH), or Western Steppe Pastoralists, is the name given to a distinct ancestral component first identified in individuals from the Chalcolithic steppe around the turn of the 5th millennium BC, subsequently detected in several genetically similar or directly related ancient populations including the Khvalynsk, Repin, Sredny Stog, and Yamnaya cultures, and found in substantial levels in contemporary European, Central Asian, South Asian and West Asian populations. This ancestry is often referred to as Yamnaya ancestry, Yamnaya-related ancestry, Steppe ancestry or Steppe-related ancestry.
The genetic history of Africa summarizes the genetic makeup and population history of African populations in Africa, composed of the overall genetic history, including the regional genetic histories of North Africa, West Africa, East Africa, Central Africa, and Southern Africa, as well as the recent origin of modern humans in Africa. The Sahara served as a trans-regional passageway and place of dwelling for people in Africa during various humid phases and periods throughout the history of Africa. It also served as a biological barrier that restricted geneflow between the northern and central parts of Africa since its desertification, contributing to the diverse and distinct population structures on the continent. Nonetheless, this did not stop contact between peoples north and south of the Sahara at various points, especially in prehistoric times when the climate conditions were warmer and wetter.
The outlined scenario is complicated by the need to account for the Basal Eurasian population (Fig. 1A, green), a group30 that split from other Eurasians soon after the main Out of Africa expansion, hence also before the split between East and West Eurasians. This population was isolated from other Eurasians and later on, starting from at least ~25 kya31,32, admixed with populations from the Middle East. Their ancestry was subsequently carried by the population expansions associated with the Neolithic revolution to all of West Eurasia.
Neolithic Iran and Natufians could be derived from the same Basal Eurasian population but are genetically closer to EHG and WHG respectively. We take the model of Fig. S4.9 and attempt to fit Natufians as a mixture of the same Basal Eurasian population that contributes to Iran_N and any other population of the tree. Several solutions are feasible, and we show the best one (lowest ADMIXTUREGRAPH score) in Fig. S4.10. We can add both EHG and MA1 as simple branches to the model structure of Fig. S4.10 and show the results in Fig. S4.11. An interesting aspect of this model is that it derives both Natufians and Iran_N from Basal Eurasians but Natufians have ancestry from a population related to WHG, while Iran_N has ancestry related to EHG. Natufians and Iran_N may themselves reside on clines of WHG-related/EHG-related admixture.
It has been previously speculated that isolated basal Eurasian lineage descendants in the central Zagros Mountains of Iran, who were the first goatherds, spread afterwards into the Eurasian steppe (Broushaki et al. 2016; Lazaridis et al. 2016). Also the ancient Iberomaurusian specimens could be in part descendants of basal Eurasians (van de Loosdrecht et al. 2018)
Our results showed that the genetic component closest to the Hub population is represented in ancient and modern populations in the Persian Plateau. Such a component, after mixing with Basal and East Eurasian ancestries, resurfaced in the palaeogenetic record, previously referred to as the Iranian Neolithic, the Iranian Hunter Gatherer' or the East Meta49.
According to this model, East Mediterranean dogs are modeled as a mixture of a basal branch (splitting deeper than the divergence of the Asian and European dogs) and West European dogs, again in agreement with current models of genetic history of West Asian human populations who are modeled as a mixture of 'basal Eurasians' and West European hunter–gatherers (Lazaridis et al., 2016; Lipson et al., 2017).
Given that the Q1 (Bedouin) have the greatest proportion of Arab genetic ancestry measured in contemporary populations (Hodgson et al. 2014; Shriner et al. 2014) and are among the best genetic representatives of the autochthonous population on the Arabian Peninsula, these two conclusions therefore point to the Bedouins being direct descendants of the earliest split after the out-of-Africa migration events that established a basal Eurasian population (Lazaridis et al. 2014). This is also consistent with the majority of Q1 (Bedouin) being able to trace a significant portion of their autosomal ancestry through lineages that never left the peninsula after the out-of-Africa migration events since such deep ancestry would not be expected if the entire Arabian Peninsula population had been reestablished from Africa or a non-African population at a later point.