Cheddar Man

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Cheddar Man
Cheddar Man scull.jpg
Common nameCheddar Man
SpeciesHomo sapiens
Age9100 BP
Place discoveredGough's Cave
Date discovered1903

Cheddar Man is a human male fossil found in Gough's Cave in Cheddar Gorge, Somerset, England. The skeletal remains date to the Mesolithic (ca. 9100 BP, 7100 BC) and it appears that he died a violent death. A large crater-like lesion just above the skull's right orbit suggests that the man may have also been suffering from a bone infection.

Excavated in 1903, Cheddar Man is Britain's oldest complete human skeleton. The remains are kept by London's Natural History Museum, in the Human Evolution gallery.[1]

Analysis of his nuclear DNA indicates that he was a typical member of the western European population at the time, with lactose intolerance, probably with light-coloured eyes (most likely green but possibly blue or hazel), dark brown or black hair, and dark/dark-to-black skin, although an intermediate skin colour cannot be ruled out.[2]

Nuclear DNA sequence data[]

The upper body of the Cheddar Man

Nuclear DNA was extracted from the petrous part of the temporal bone by a team from the Natural History Museum in 2018.[3][4] While the genetic markers recovered from Cheddar Man were incomplete, they suggested (based on their associations in modern populations whose phenotypes are known) that he probably[5] had green eyes, lactose intolerance, dark curly or wavy hair, and dark/dark-to-black skin, although an intermediate skin colour cannot be ruled out.[2][a][6] These features are typical of the Western European population of the time, now known as Western Hunter-Gatherers, another example being Loschbour man discovered in Luxembourg. This population forms about 10%, on average, of the ancestry of Britons without a recent family history of immigration.[2]

Genetic change since the Mesolithic[]

Brown eyes, lactose tolerance, and light skin are common in the modern population of the area. These genes came from later immigration, most of it ultimately from two major waves, the first of Neolithic farmers from the Near East, another of Bronze Age pastoralists, most likely speakers of Indo-European languages, from the Pontic steppe.[2][7]

Cheddar Man's Y-DNA belonged to an ancient sister branch of modern I2-L38 (I2a2).[2] The I2a2 subclade is still extant in males of the modern British Isles and across other parts of Europe. The mitochondrial DNA of Cheddar Man was discovered to be haplogroup U5b1 by a Natural History Museum study in 2018 using next generation sequencing.[2] Some 65% of western European Mesolithic hunter-gatherers had haplogroup U5; today it is widely distributed, at lower frequencies, across western Eurasia and northern Africa. In 1996, Bryan Sykes of the University of Oxford first sequenced the mitochondrial DNA from one of Cheddar Man's molars as U5a using PCR testing. The difference between the older result and the 2018 Natural History Museum result was attributed to the use of older PCR technology and possible contamination[8].[9][10][11]

See also[]

Notes[]

  1. ^ 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".[4]

References[]

  1. ^ "Human Evolution", www.nhm.ac.uk, Natural History Museum, retrieved 17 November 2017
  2. ^ a b c d e f 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), "Ancient genomes indicate 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 (p.18-19): "This individual has light or blue/green eye colour, it is not light blue, there are elements of brown/yellow in the eye to give a proposed perceived green colour. Better coverage at the low sequenced marker would clarify this but blue/hazel cannot be ruled out. It is certainly not a brown eyed or clear blue-eyed individual... Skin pigmentation [assumptions about missing information omitted] The following range for skin pigmentation prediction is possible for this individual with these parameters:... Intermediate 0.152 - 0.038 Dark-Black 0.848 - 0.962 Final prediction: Dark/Dark-to-Black skin If we omit the three missing alleles, our tool produces 0.752 and 0.248 probabilities for the intermediate and dark-black category respectively, changing the prediction ranges to 0.752- 0.038 and 0.248-0.962. However, note that this completely removes the locus from the prediction model; hence the prediction will not perform optimally (how the prediction model was made). It is therefore best to have some allele present to infer the most probable range for Cheddar Man and we derive the ranges above from the extreme allele constellations only. Explanation: The missing loci certainly impact on this prediction; however, utilizing the input of all ancestral alleles is the preferred option over the use of the derived alleles at these loci – hence 0.152 for intermediate and 0.848 for Dark-to-Black would be the most probable profile. That being said a broad range is present in both the intermediate and dark-black categories due to the missing loci. Also, this effect of skipping a skin pigmentation prediction category with regards probability values, tends to be observed more often in admixed individuals. What is important to note is the input of the dark-black prediction is significant on the intermediate category and therefore it is acceptable to propose a dark complexion individual over an intermediate/light prediction even though the intermediate range is present. It is unlikely that this individual has the darkest possible pigmentation, but it cannot be ruled out. Better sequencing coverage would clarify to what degree this individual has a dark complexion."
  3. ^ "Ancient 'dark skinned' Cheddar man find may not be true". New Scientist. 21 February 2018. Retrieved 22 May 2018.
  4. ^ a b 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.
  5. ^ "Ancient 'dark-skinned' Briton Cheddar Man find may not be true". Retrieved 18 March 2021.
  6. ^ "Cheddar Man FAQ". www.nhm.ac.uk. Retrieved 18 March 2018.
  7. ^ Haak, Wolfgang; Lazaridis, Iosif; Patterson, Nick; Rohland, Nadin; Mallick, Swapan; Llamas, Bastien; Brandt, Guido; Nordenfelt, Susanne; Harney, Eadaoin; Stewardson, Kristin; Fu, Qiaomei; Mittnik, Alissa; Bánffy, Eszter; Economou, Christos; Francken, Michael; Friederich, Susanne; Pena, Rafael Garrido; Hallgren, Fredrik; Khartanovich, Valery; Khokhlov, Aleksandr; Kunst, Michael; Kuznetsov, Pavel; Meller, Harald; Mochalov, Oleg; Moiseyev, Vayacheslav; Nicklisch, Nicole; Pichler, Sandra L.; Risch, Roberto; Guerra, Manuel A. Rojo; Roth, Christina; Szécsényi-Nagy, Anna; Wahl, Joachim; Meyer, Matthias; Krause, Johannes; Brown, Dorcas; Anthony, David; Cooper, Alan; Alt, Kurt Werner; Reich, David (10 February 2015). "Massive migration from the steppe is a source for Indo-European languages in Europe". arXiv:1502.02783. Bibcode:2015Natur.522..207H. bioRxiv 10.1101/013433. doi:10.1038/nature14317.
  8. ^ Cheddar Man & the Origins of the British (Dr. Tom Booth)
  9. ^ Bramanti, B; Thomas, MG; Haak, W (October 2009). "Genetic discontinuity between local hunter-gatherers and central Europe's first farmers". Science. 326 (5949): 137–40. Bibcode:2009Sci...326..137B. doi:10.1126/science.1176869. PMID 19729620. S2CID 206521424.
  10. ^ Malmström, H; Gilbert, MT; Thomas, MG (November 2009). "Ancient DNA reveals lack of continuity between neolithic hunter-gatherers and contemporary Scandinavians". Current Biology. 19 (20): 1758–62. doi:10.1016/j.cub.2009.09.017. PMID 19781941.
  11. ^ Sykes, Bryan, Blood of the Isles (Bantam, 2006) pp. 5–12

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