Dr. Reich and his colleagues also tracked changes in the color of European skin.
The original hunter-gatherers, descendants of people who had come from Africa, had dark skin as recently as 9,000 years ago. Farmers arriving from Anatolia were lighter, and this trait spread through Europe. Later, a new gene variant emerged that lightened European skin even more.
Why? Scientists have long thought that light skin helped capture more vitamin D in sunlight at high latitudes. But early hunter-gatherers managed well with dark skin. Dr. Reich suggests that they got enough vitamin D in the meat they caught.
He hypothesizes that it was the shift to agriculture, which reduced the intake of vitamin D, that may have triggered a change in skin color.
https://www.nytimes.com/2015/11/24/science/agriculture-linked-to-dna-changes-in-ancient-europe.html
Evidence for this comes from a study by an international team of scientists, published last month in the journal Nature. The team, led by population geneticists Iain Mathieson, David Reich, and colleagues from Harvard Medical School, analyzed the genomes of 230 people from archaeological sites across Europe who lived between 2,300 and 8,000 years ago, and compared them to the genomes of modern Europeans, gleaned from the 1000 Genomes Project.
The spread of the light-skin genes in the wake of farming, Mathieson, Reich, and colleagues suggest, may have a similar explanation: since the farmers’ diet was less heavy in meat than that of the hunter-gatherers, their vitamin D intake was reduced. Pale skin enabled wheat-eating farmers to combat vitamin deficiency.
https://carlzimmer.com/agriculture-linked-to-dna-changes-in-ancient-europe-78/
So then East Asians previously where genetically more connected to African traits as well:
https://scihubtw.tw/https://doi.org/10.1126/science.aba0909
So this has also been found in the "New World" as well - the African "traits" were the norm until agriculture arose...
And so just as in East Asia, so too did Europeans have African traits until recently:
Anders Götherstörm, head of archaeogenetic research at the archaeological research laboratory at Stockholm University, said: 'Our results stress the importance Anatolia has had on Europe's prehistory.
'But to fully understand how the agricultural development proceeded we need to dive deeper down into material from the Levant.'
The researchers extracted DNA from human remains found at the site of an ancient settlement in Kumtepe in Troas, northwestern Anatolia, in Turkey.
The remains are thought to belong to Neolithic farmers who were among the first inhabitants of the settlement, which eventually gave rise to the city of Troy.
The team behind the study compared the DNA with genetic material from other ancient farmers in Europe along with DNA from modern Europeans.
Ayca Omrak, who was the first author of the research at Stockholm University, said: 'I have never worked with a more complicated material.
'I could use the DNA from the Kumptepe material to trace the European farmers back to Anatolia.
'It is also fun to have worked with this material from the Kumtepe site, as this is the precursor to Troy.'
A separate study recently found that a rise in farming and metal work in Ireland led to a 'genetic shift' in the region, fuelled by an influx of people from the Black Sea and the Middle East.
Genes responsible for lighter skin in northern populations were also far less prevalent in prehistoric Europeans.
However, it appears the early farmers from Anatolia who migrated into Europe in the Neolithic period also carried some genes for lighter skin colour with them.
Those Neolithic farmers mostly had light skin and dark eyes — the opposite of many of the hunter-gatherers with whom they now lived side by side. “They looked different, spoke different languages … had different diets,” says Hartwick College archaeologist David Anthony. “For the most part, they stayed separate.”
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