Chuck Bednar for redOrbit.com – @BednarChuck
Europeans didn’t always have the pale white skin that we commonly associate with them – in fact, the trait evolved fairly recently, according to new research presented last week at the 84th annual meeting of the American Association of Physical Anthropologists.
In fact, according to Science, the research team behind the new study found that characteristics such as pale skin, height, and the ability to digest milk as adults arrived in the continent recently, and that European peoples have drastically changed over the last 8,000 years or so.
Taking a closer look at Europe’s genetic history
The new study is just the latest in a long line of recent research that has probed the genetic roots of Europeans, the website explained. For instance, by comparing key parts of the DNA across the genomes of 83 ancient individuals from archaeological sites all over Europe, scientists found that the continent’s current residents are a mix of at least three different ancient populations.
The team responsible for that study is also behind the new one, and they took a closer look at the ancient European genome in comparison to more recent DNA from the region. They located five genes associated with changes and diet and skin pigmentation that had undergone strong natural selection, confirming earlier research that early European hunter-gatherers could not digest milk sugars.
In terms of skin color, they found different evolutionary patterns in different areas, including a trio of different genes responsible for producing lighter-colored skin. Their research discovered that as of about 8,500 years ago, early-hunter gatherers in Spain, Luxembourg, and Hungary still had darker skin and lacked versions of the two genes (SLC24A5 and SLC45A2) that caused the depigmentation process to occur and the color of European skin to become white.
A more detailed picture of how natural selection works
Furthermore, it was found that in the far northern regions (where pale skin would be beneficial due to the low levels of light), hunter-gatherers from a nearly 8,000-year-old site in southern Sweden were found to have both light skin gene variants, as well as HERC2/OCA2, a gene that is involved in the development of blue eyes, blonde hair, and lighter skin.
“Thus ancient hunter-gatherers of the far north were already pale and blue-eyed, but those of central and southern Europe had darker skin,” Ann Gibbons of Science explained. “Then, the first farmers from the Near East arrived in Europe; they carried both genes for light skin.”
As those farmers interbred with the indigenous hunter-gatherers, one of their light-skin genes started to sweep across Europe. The other gene variant remained at low levels until roughly 5,800 years ago, when it too started to become increasingly frequent in Europeans.
They also found that natural selection favored genetic variants for tallness among those living in parts of Europe starting 8,000 years ago. The research, Penn State anthropological geneticist George Perry told Science, gives “a much more detailed picture now of how selection works.”
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