Western Hunter-Gatherer

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Cheddar Man, found in Great Britain, was found to have Western Hunter-Gatherer genotype.

In archaeogenetics, the term Western Hunter-Gatherer (WHG), West European Hunter-Gatherer or Western European Hunter-Gatherer names a distinct ancestral component of modern Europeans, representing descent from a population of Mesolithic hunter-gatherers scattered over Western, Southern and Central Europe, from the British Isles in the west to the Carpathians in the east.[1]

Along with the Scandinavian Hunter-Gatherers (SHG) and Eastern Hunter-Gatherers (EHG), the WHGs constituted one of the three main genetic groups in the postglacial period of early Holocene Europe.[2] The border between WHGs and EHGs ran roughly from the lower Danube, northward along the western forests of the Dnieper towards the western Baltic Sea.[1]

SHGs were in turn an equal mix of WHGs and EHGs. Once the main population throughout Europe, the WHGs were largely displaced by successive expansions of Early European Farmers (EEFs) during the early Neolithic, but experienced a resurgence during the Middle Neolithic, mainly mediated by WHG males mating with EEF females. During the Late Neolithic and Early Bronze Age, Western Steppe Herders (WSHs) from the Pontic–Caspian steppe embarked on a massive expansion, which further displaced the WHGs. Among modern-day populations, WHG ancestry is most common among populations of the eastern Baltic.

Research[edit]

Lazaridis et al. (2014) identified Western Hunter-Gatherers (WHG) as a distinct ancestral component. They were found to have contributed ancestry to all modern Europeans, including Early European Farmers (EEF), who were, however, mostly of Anatolian descent. They suggested that WHGs separated from eastern Eurasians around 40,000 BP, and from Ancient North Eurasians (ANE) around 24,000 BP.[3]

Haak et al. (2015) found that WHG ancestry in Western Europe had a resurgence from the Early Neolithic to the Middle Neolithic.[4]

Mathieson et al. (2015) found that most Europeans could be modeled as a mixture of WHG, EEF and peoples from the Yamnaya culture of the Pontic–Caspian steppe.[5]

Lazaridis et al. (2015) found that WHGs were a mix of Eastern Hunter-Gatherers (EHGs) and the Upper Paleolithic people (Cro-Magnon) of the Grotte du Bichon in Switzerland. EHGs in turn derived 75% of their ancestry from ANEs. Scandinavian Hunter-Gatherers (SHGs) were found to be a mix of EHGs and WHGs.[a]

Jones et al. (2017) determined that the people of the Mesolithic Kunda culture and the Narva culture of the eastern Baltic were a mix of WHG and EHG, showing the closest affinity with WHG. Samples from the Ukrainian Mesolithic and Neolithic were found to cluster tightly together between WHG and EHG, suggesting genetic continuity in the Dnieper Rapids for a period of 4,000 years. The Ukrainian samples belonged exclusively to the maternal haplogroup U, which is found in around 80% of all European hunter-gatherer samples.[7]

Saag et al. (2017) found that people of the Pit–Comb Ware culture (CCC) of the eastern Baltic were closely related to EHG, unlike earlier hunter-gatherers in the area, who were more closely related to WHG.[8]

Günther et al. (2018) analyzed 13 SHGs and found all of them to be of WHG ancestry, however that SHGs from western and northern Scandinavia had less WHG ancestry (ca 51%) than individuals from eastern Scandinavia (ca. 62%). The authors suggested that the SHGs were a mix of WHGs who had migrated into Scandinavia from the south, and EHGs who had later migrated into Scandinavia from the northeast along the Norwegian coast. The WHGs who entered Scandinavia are believed to have belonged to the Ahrensburg culture. EHGs and WHGs displayed lower allele frequencies of SLC45A2 and SLC24A5, which cause depigmentation, and OCA/Herc2, which causes light eye color, than SHGs.[9]

Mittnik et al. (2018) found that southern areas of the eastern Baltic, in particular members of the Kunda and Narva cultures, were found to be more closely related to WHG, while the Pit–Comb Ware culture was more closely related to EHG. Unlike most WHGs, the WHGs of the eastern Baltic did not receive European farmer admixture during the Neolithic. Modern populations of the eastern Baltic thus harbors a larger amount of WHG ancestry than any other population in Europe.[10]

Mathieson et al. (2018) included an analysis of a large number of individuals of prehistoric Europe. The DNA of eleven WHGs from the Upper Palaeolithic and Mesolithic in Western Europe, Central Europe and the Balkans was analyzed, with regards to their Y-DNA haplogroups and mtDNA haplogroups. Of the nine samples of Y-DNA extracted, six belonged to I haplotypes (particularly subclades of I2a), one belonged to C1a2, one belonged to R, and one possibly belonged to J. Of the eleven samples of mtDNA extracted, nine belonged to U5b1 haplotypes, one belonged to U5a2c, and one belonged to an U2 haplotype. These results suggested that WHGs were once widely distributed from the Atlantic coast in the West, to Sicily in the South, to the Balkans in the Southeast, for more than six thousand years.[11] The study also included an analysis of a large number of individuals of prehistoric Eastern Europe. Thirty-seven samples were collected from Mesolithic and Neolithic Ukraine (9500-6000 BC). These were determined to be an intermediate between EHG and SHG, although WHG ancestry in this population increased during the Neolithic. Samples of Y-DNA extracted from these individuals belonged exclusively to R haplotypes (particularly subclades of R1b1) and I haplotypes (particularly subclades of I2). mtDNA belonged almost exclusively to U (particularly subclades of U5 and U4).[11] A large number of individuals from the Zvejnieki burial ground, which mostly belonged to the Kunda culture and Narva culture in the eastern Baltic, were analyzed. These individuals were mostly of WHG descent in the earlier phases, but over time EHG ancestry became predominant. The Y-DNA of this site belonged almost exclusively to haplotypes of haplogroup R1b1a1a and I2a1. The mtDNA belonged exclusively to haplogroup U (particularly subclades of U2, U4 and U5).[11] Forty individuals from three sites of the Iron Gates Mesolithic in the Balkans were also analyzed. These individuals were estimated to be of 85% WHG and 15% EHG descent. The males at these sites carried exclusively haplogroup R1b1a and I (mostly subclades of I2a) haplotypes. mtDNA belonged mostly to U (particularly subclades of U5 and U4).[11] People of the Balkan Neolithic were found to harbor 98% Anatolian ancestry and 2% WHG ancestry. By the Chalcolithic, people of the Cucuteni–Trypillia culture were found to harbor about 20% hunter-gatherer ancestry, which was intermediate between EHG and WHG. People of the Globular Amphora culture were found to harbor ca. 25% WHG ancestry, which is significantly higher than Middle Neolithic groups of Central Europe.[11]

Antonio et al. (2019) examined remains out of the Grotta Continenza in Italy. Of the six paternal haplogroups the three buried between ca. 10,000 BC and 7000 BC were of I2a-P214); of the presumably WHG maternal haplogroups were two U5b1 and one U5b3.[12][13] Around 6000 BC, the WHGs of Italy were almost completely genetically replaced by EEFs (two G2a2) and one Haplogroup R1b, although WHG ancestry slightly increased in subsequent millennia.[14]

Neolithic individuals in the British Isles were close to Iberian and Central European Early and Middle Neolithic populations, modelled as having about 75% ancestry from EEF with the rest coming from WHG in continental Europe. They subsequently replaced most of the WHG population in the British Isles without mixing much with them.[15]

Physical appearance[edit]

According to David Reich, DNA analysis has shown that Western Hunter Gatherers were typically dark skinned, dark haired, and blue eyed.[16] Archaeologist Graeme Warren has said that their skin color ranged from olive to black, and speculated that they may have had some regional variety of eye and hair colors.[17] This is strikingly different from the Eastern Hunter-Gatherers (EHG)—who have been suggested to be light-skinned, brown-eyed or blue eyed and dark-haired or light-haired.[18]

Two WHG skeletons with incomplete SNPs, La Braña and Cheddar Man, are predicted to have had dark or dark-to-black skin, whereas two other WHG skeletons with complete SNPs, "Sven" and Loschbour man, are predicted to have had dark/intermediate and intermediate skin, respectively.[19][9][b]

Notes[edit]

  1. ^ Eastern Hunter Gatherers (EHG) derive 3/4 of their ancestry from the ANE... Scandinavian hunter-gatherers (SHG) are a mix of EHG and WHG; and WHG are a mix of EHG and the Upper Paleolithic Bichon from Switzerland.[6]
  2. ^ These predictions were obtained using a multinomial logistic regression model based on a panel of 36 carefully selected SNPs with a low sensitivity of 0.26 for classifying intermediate skin (compared to 0.99 and 0.90 for white and black skin, respectively). The accuracy of the model used could be further improved with "additional (but currently unknown) SNP predictors once identified via future GWAS".[20]

References[edit]

  1. ^ a b Anthony 2019b, p. 28.
  2. ^ Kashuba 2019: "Earlier aDNA studies suggest the presence of three genetic groups in early postglacial Europe: Western hunter–gatherers (WHG), Eastern hunter–gatherers (EHG), and Scandinavian hunter–gatherers (SHG)4. The SHG have been modelled as a mixture of WHG and EHG."
  3. ^ Lazaridis 2014.
  4. ^ Haak 2015.
  5. ^ Mathieson 2015.
  6. ^ Lazaridis 2016.
  7. ^ Jones 2017.
  8. ^ Saag 2017.
  9. ^ a b Günther 2018.
  10. ^ Mittnik 2018.
  11. ^ a b c d e Mathieson 2018.
  12. ^ Antonio et al. 2019, Table 2 Sample Information, Rows 4-6.
  13. ^ Antonio et al. 2019, p. 1.
  14. ^ Antonio et al. 2019, p. 2, Fig. 1.
  15. ^ Brace, Selina; Diekmann, Yoan; Booth, Thomas J.; van Dorp, Lucy; Faltyskova, Zuzana; Rohland, Nadin; Mallick, Swapan; Olalde, Iñigo; Ferry, Matthew; Michel, Megan; Oppenheimer, Jonas; Broomandkhoshbacht, Nasreen; Stewardson, Kristin; Martiniano, Rui; Walsh, Susan; Kayser, Manfred; Charlton, Sophy; Hellenthal, Garrett; Armit, Ian; Schulting, Rick; Craig, Oliver E.; Sheridan, Alison; Parker Pearson, Mike; Stringer, Chris; Reich, David; Thomas, Mark G.; Barnes, Ian (2019). "Ancient genomes indicate population replacement in Early Neolithic Britain". Nature Ecology & Evolution. 3 (5): 765–771. doi:10.1038/s41559-019-0871-9. ISSN 2397-334X. PMC 6520225. PMID 30988490.
  16. ^ Reich, David (2018). Who We Are and How We Hot Here : Ancient DNA and the New Science of the Human Past (First ed.). New York: Knopf Doubleday Publishing Group. ISBN 978-1101870334. "Analysis of ancient DNA data shows that the hunter-gatherers of Western Europe some eight thousand years ago had blue eyes but dark skin and dark hair, a combination that is rare today."
  17. ^ Warren, Graeme (2021). Hunter-Gatherer Ireland: making connections in an island world. Oxbow Books. ISBN 978-1789256840. "WHGs for example, had skin pigmentation ranging from olive to brown to black, with blue or blue-green eyes. In some parts of Europe this may also have been associated with blond hair."
  18. ^ Population genomics of Mesolithic Scandinavia: Investigating early postglacial migration routes and high-latitude adaptation S8 Text. Functional variation in ancient samples., doi:10.1371/journal.pbio.2003703.s013
  19. ^ Brace, Selina; Diekmann, Yoan; Booth, Thomas J.; Faltyskova, Zuzana; Rohland, Nadin; Mallick, Swapan; Ferry, Matthew; Michel, Megan; Oppenheimer, Jonas; Broomandkhoshbacht, Nasreen; Stewardson, Kristin; Walsh, Susan; Kayser, Manfred; Schulting, Rick; Craig, Oliver E.; Sheridan, Alison; Pearson, Mike Parker; Stringer, Chris; Reich, David; Thomas, Mark G.; Barnes, Ian (2019), "Population Replacement in Early Neolithic Britain", Nature Ecology & Evolution, 3 (5): 765–771, doi:10.1038/s41559-019-0871-9, PMC 6520225, PMID 30988490 Supplementary Material. Page 22: "Two WHGs (Cheddar Man and La Braña from northern Spain) are predicted to have had dark or dark-to-black skin, whereas one (Loschbour44from Luxembourg) is predicted to have had intermediate skin suggesting but we find potential temporal and/or geographical variation in pigmentation characteristics, suggesting that diverse skin pigmentation levels coexisted in WHGs by at least ca.8 kBP. Sven was predicted to have had dark to intermediate to dark skin in line with the current hypothesis that alleles commonly associated with lighter skin in Europeans were introduced to north-western Europe by ANFs."
  20. ^ Walsh, Susan (2017). "Global skin colour prediction from DNA". Human Genetics. 136 (7): 847–863. doi:10.1007/s00439-017-1808-5. PMC 5487854. PMID 28500464.

Bibliography[edit]

Further reading[edit]