If you've watched the Channel 4 documentary The First Brit: Secrets of the 10,000 Year Old Man, or read about the Museum's research into Cheddar Man, you may have some further questions you'd like answered.
Here are our researchers' responses to some of the most popular queries they've received.
How can DNA survive 10,000 years?
DNA can survive in bones and teeth for extraordinary lengths of time given the right environmental conditions. The oldest ancient DNA extracted to date is probably that from a horse bone which was preserved in the Canadian permafrost for over 550,000 years1. DNA survives less well in bones from temperate environments, but cave environments seem to provide some protection. Ancient DNA has been successfully extracted and analysed from 35,000 year-old human remains from Europe2. The good preservation of the DNA we retrieved from Cheddar Man is unusual, but not unexpected.
How do you know his skin colour?
We were able to extract enough information from Cheddar Man’s DNA to run it through a forensic tool that predicts differences in the level of skin pigmentation in modern world populations3. The results indicated that Cheddar Man’s skin pigmentation was most likely in one of the two most highly-pigmented of five categories ('dark' or 'dark to black'), and definitely not in the lightest categories.
Is this a surprising finding?
No, not really. Previous studies of DNA from Mesolithic individuals recovered from Spain, Luxembourg and Hungary identified that they also lacked the versions of genes associated with reduced skin pigmentation in modern, light-skinned Europeans4-6. We found that Cheddar man belonged to the same population as these individuals – usually referred to as western European Mesolithic hunter-gatherers – so in that context his pigmentation is not unusual. However, we did predict how dark Cheddar Man’s skin was by examining variation in a wider range of genes related to skin pigmentation.
Will these findings be published in a peer-reviewed paper?
We are preparing a related paper for submission, but this paper is not exclusively about Cheddar Man. As previous studies had already suggested that darker skin pigmentation was common in western European Mesolithic hunter-gatherers, the results from Cheddar Man are not novel enough by themselves to form the basis of a scientific paper. But finding that he was typical of that population was novel, and when put in the context of subsequent migrations into Britain, his genome becomes a valuable piece of the British population history jigsaw.
Is Cheddar Man actually an escaped slave or a tourist from Africa?
No! The bones of Cheddar Man have been radiocarbon dated twice, and on both occasions the results indicate that he died around 10,000 years ago7.
Are there any people with lighter skin pigmentation at this time?
Yes. Populations with the versions of genes primarily responsible for lighter skin pigmentation were living in parts of Scandinavia and western Asia at around the time Cheddar man was alive5,8-9.
How did Europeans develop paler skin?
The versions of the genes primarily responsible for lighter skin pigmentation in modern North-West Europeans arrive in Europe on the back of two waves of migration thousands of years after Cheddar Man died; one associated with Near Eastern farmers and another with pastoralists from the Pontic steppe10-12. In addition, there seems to have been ongoing natural selection favouring lighter skin pigmentation in Europe over the last 9,000 years, probably in relation to an increased need for UV induced vitamin D synthesis in the skin.
What is his mitochondrial DNA type?
Cheddar Man’s mitochondrial DNA, which is inherited exclusively down the maternal line, belongs to haplogroup U5b1. As this is only a tiny portion of an individual’s genome, and there have been several large-scale population movements in Europe and across the world since Cheddar Man was alive, this result has no relevance to his skin pigmentation, and says little about the distribution of this mitochondrial haplogroup amongst modern populations.
How do we calculate that 10% of British ancestry can be linked to Cheddar Man?
When we look at genetic variation in modern British people today, we find that – for those who do not have a recent history of migration – around 10% of their ancestry can be attributed to the ancient European population to which Cheddar Man belonged. This group is referred to as the western European Mesolithic hunter-gatherers. However, this ancestry does not relate specifically to Cheddar Man or the Mesolithic population of Britain. Well after Cheddar Man’s death, two large-scale prehistoric migrations into Britain produced significant population turnovers13. Both of these migrations into Britain represented westward extensions of population movements across Europe10-12. In both cases, these migrating populations intermixed with local people who carried western European Mesolithic hunter-gatherer ancestry, as they moved across Europe. When these populations arrived in Britain they already had some hunter-gatherer ancestry derived from this mixing with local populations. Therefore the majority of western European Mesolithic hunter-gatherers ancestry that we see in modern British people probably originates from populations who lived all over Europe during the Mesolithic, which was carried into Britain by these later migrations.
References
1Orlando, L., Ginolhac, A., Zhang, G., Froese, D., Albrechtsen, A., Stiller, M., Schubert, M., Cappellini, E., Petersen, B., Moltke, I. and Johnson, P.L. et al. 2013. Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse. Nature, 499(7456), p.74.
2Fu, Q., Posth, C., Hajdinjak, M., Petr, M., Mallick, S., Fernandes, D., Furtwängler, A., Haak, W., Meyer, M., Mittnik, A. and Nickel, B. et al. 2016. The genetic history of ice age Europe. Nature, 534(7606), p.200.
3Walsh, S., Chaitanya, L., Breslin, K., Muralidharan, C., Bronikowska, A., Pospiech, E., Koller, J., Kovatsi, L., Wollstein, A., Branicki, W. and Liu, F. et al. 2017. Global skin colour prediction from DNA. Human genetics, 136(7), pp.847-863.
4Olalde, I., Allentoft, M.E., Sánchez-Quinto, F., Santpere, G., Chiang, C.W., DeGiorgio, M., Prado-Martinez, J., Rodríguez, J.A., Rasmussen, S., Quilez, J. and Ramírez, O. et al. 2014. Derived immune and ancestral pigmentation alleles in a 7,000-year-old Mesolithic European. Nature, 507(7491), p.225.
5Jones, E.R., Gonzalez-Fortes, G., Connell, S., Siska, V., Eriksson, A., Martiniano, R., McLaughlin, R.L., Llorente, M.G., Cassidy, L.M., Gamba, C., Meshveliani, T. et al. 2015. Upper Palaeolithic genomes reveal deep roots of modern Eurasians. Nature communications, 6, p.8912.
6Gamba, C., Jones, E.R., Teasdale, M.D., McLaughlin, R.L., Gonzalez-Fortes, G., Mattiangeli, V., Domboróczki, L., Kővári, I., Pap, I., Anders, A., Whittle, A. et al. 2014. Genome flux and stasis in a five millennium transect of European prehistory. Nature communications, 5, p.5257.
7Meiklejohn, C., Chamberlain, A.T. & Schulting, R.J., 2011. Radiocarbon dating of Mesolithic human remains in Great Britain. Mesolithic Miscellany, 21(2), pp.20-58.
8Gallego-Llorente, M., Connell, S., Jones, E.R., Merrett, D.C., Jeon, Y., Eriksson, A., Siska, V., Gamba, C., Meiklejohn, C., Beyer, R. and Jeon, S., 2016. The genetics of an early Neolithic pastoralist from the Zagros, Iran. Scientific reports, 6, p.31326.
9Günther, T., Malmström, H., Svensson, E.M., Omrak, A., Sánchez-Quinto, F., Kılınç, G.M., Krzewińska, M., Eriksson, G., Fraser, M., Edlund, H. and Munters, A.R., 2018. Population genomics of Mesolithic Scandinavia: Investigating early postglacial migration routes and high-latitude adaptation. PLoS biology, 16(1), p.e2003703.
10Haak, W., Lazaridis, I., Patterson, N., Rohland, N., Mallick, S., Llamas, B., Brandt, G., Nordenfelt, S., Harney, E., Stewardson, K. and Fu, Q. et al. 2015. Massive migration from the steppe was a source for Indo-European languages in Europe. Nature, 522(7555), p.207.
11Allentoft, M.E., Sikora, M., Sjögren, K.G., Rasmussen, S., Rasmussen, M., Stenderup, J., Damgaard, P.B., Schroeder, H., Ahlström, T., Vinner, L. and Malaspinas, A.S., 2015. Population genomics of bronze age Eurasia. Nature, 522(7555), p.167.
12Mathieson, I., Lazaridis, I., Rohland, N., Mallick, S., Patterson, N., Roodenberg, S.A., Harney, E., Stewardson, K., Fernandes, D., Novak, M. and Sirak, K., 2015. Genome-wide patterns of selection in 230 ancient Eurasians. Nature, 528(7583), p.499.
13Olalde, I., Brace, S., Allentoft, M.E., Armit, I., Kristiansen, K., Rohland, N., Mallick, S., Booth, T., Szécsényi-Nagy, A., Mittnik, A. and Altena, E., 2017. The Beaker phenomenon and the genomic transformation of northwest Europe. bioRxiv, pp.1-28.
Cheddar Man: Mesolithic Britain's blue-eyed boy
Ancient DNA from Cheddar Man has helped Museum scientists paint a portrait of one of the oldest modern humans in Britain.
Explore human evolution
Museum science is helping to answer where, when and how humans evolved.
Research funded by
Scientific paper
The scientific research behind this work is detailed in the preprint paper Population Replacement in Early Neolithic Britain.
Pigmentation data
Download the Cheddar Man pigmentation genetics data here.