In archaeogenetics, the term Western Hunter-Gatherer, West European Hunter-Gatherer or Western European Hunter-Gatherer, is the name given to a distinct ancestral component that represents descent from Mesolithic hunter-gatherers of Western, Southern and Central Europe. The term is often abbreviated as WHG. During the Mesolithic, the WHGs inhabited an area stretching from the British Isles in the west to the Carpathians in the east.
Along with 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. 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.
SHGs were in turn an equal mix of WHGs and EHGs. Once widely dispersed throughout Europe, the WHGs were largely displaced by successive expansions of Early European Farmers (EEFs) during the early Neolithic, but experienced a male-driven resurgence during the Middle Neolithic. 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.
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 BC, and from Ancient North Eurasians (ANE) around 22,000 BC.
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.
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.
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.
Mittnik et al. (2018) found that members of the Kunda culture and Narva culture were closely related with WHG, while the Pit-Comb Ware culture was more closely related to EHG. Southern areas of the eastern Baltic were found to be more closely related to WHG than northern and eastern areas. 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.
Mathieson et al. (2018) included an analysis of a large number of individuals of prehistoric Europe. The remains of eleven WHGs from the Upper Palaeolithic and Mesolithic in Western Europe, Central Europe and the Balkans was analyzed. 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 U51b 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. 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). 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). 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). People of the Balkan Neolithic were found to harbor 98% Anatolian ancestry and 2% WGH 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.
Antonio et al. (2019) examined the remains of three males buried in Grotta Continenza in Italy between ca. 10,000 BC to 7,000 BC. They carried the paternal haplogroups I-M436 and I-M223 (two samples), and the maternal haplogroups U5b1 (two samples) and U5b3. These three individuals were determined to be WHGs. Around 6,000 BC, the WHGs of Italy were almost completely genetically replaced by EEFs, although WHG ancestry slighly increased in subsequent millennia.
It has been suggested that WHGs had dark skin and blue eyes. However, Late Mesolithic hunter-gatherers of the eastern Baltic, who were mostly of WHG ancestry, display high frequencies of the derived alleles for SLC45A2 and SLC24A5, which code for light skin.[b]
In 2020, a large study titled "Genetic variation related to the adaptation of humans to an agriculturalist lifestyle" was carried out by researchers at the University of Mainz. The genomes of over 100 ancient individuals were sequenced and analyzed. Close analysis of the pigmentation of 14 Western-Hunter-Gatherers from Central Europe was carried out. The study found that phenotypic traits such as blonde hair and blue eyes were present in WHGs, but not in EHGs. WHGs were found to have a skin colour that was slightly darker than that of Early European farmers and EHGs.
The researchers concluded that blonde-haired and blue-eyed phenotypes most likely originated in Central European WHGs:
Phenotypic reconstructions based on ancient DNA suggested that some of the hunter-gatherers of Central Europe had a unique appearance as a result of a dark skin tone in combination with light eyes and a light hair color. Blonde-haired and blue-eyed phenotypes originated in Europe before the onset of the Neolithic and rose in frequency over time. Derived alleles in related genes such as TYRP1, HERC2 and OCA2 can be found in the Central European Western-Hunter-Gatherers at elevated frequencies, in contrast to the Eastern European/Russian hunter-gatherers.