How Europeans evolved white skin

[PNGarrison]

How Europeans evolved white skin - news story about recent paper on natural selection in Europeans

http://news.sciencemag.org/archaeology/2015/04/how-europeans-evolved-white-skin?rss=1

[lgmayka]

Unfortunately, the end of the article resorts to the usual politically correct line that all selection must have been natural rather than social--as if humans live and breed mindlessly like rabbits instead of choosing their behavior (good or evil!) based on social dynamics.

An allele does not rise to fixation within a few thousand years merely through some mild biological advantage. Human choice must have been involved. Possibilities range from mate desirability to economic discrimination and even perhaps to "race war."

[1798]

"Most of us think of Europe as the ancestral home of white people. But a new study shows that pale skin, as well as other traits such as tallness and the ability to digest milk as adults, arrived in most of the continent relatively recently. The work, presented here last week at the 84th annual meeting of the American Association of Physical Anthropologists, offers dramatic evidence of recent evolution in Europe and shows that most modern Europeans don’t look much like those of 8000 years ago."

This is nonsense as the Motala 12 SHG were all pale skinned.

[1798]

"Most of us think of Europe as the ancestral home of white people. But a new study shows that pale skin, as well as other traits such as tallness and the ability to digest milk as adults, arrived in most of the continent relatively recently. The work, presented here last week at the 84th annual meeting of the American Association of Physical Anthropologists, offers dramatic evidence of recent evolution in Europe and shows that most modern Europeans don’t look much like those of 8000 years ago."

This is nonsense as the Motala 12 SHG were all pale skinned.

LBK, Stuttgart, Germany 7,500 ybp, gedmatch F999916
pale skin rs1426654 AA

[Armando]

How Europeans evolved white skin - news story about recent paper on natural selection in Europeans

http://news.sciencemag.org/archaeolo...ite-skin?rss=1

Here's the link to the pre-print of the study. http://biorxiv.org/content/early/2015/03/13/016477

Dienekes' post on the subject http://dienekes.blogspot.com/2015/03...-european.html

[PNGarrison]

Unfortunately, the end of the article resorts to the usual politically correct line that all selection must have been natural rather than social--as if humans live and breed mindlessly like rabbits instead of choosing their behavior (good or evil!) based on social dynamics.

An allele does not rise to fixation within a few thousand years merely through some mild biological advantage. Human choice must have been involved. Possibilities range from mate desirability to economic discrimination and even perhaps to "race war."

Take a calculator and raise 1.01 to the 90th power (3 generations per century times 30 centuries) and see what you get. A small selective advantage can indeed lead to a rapid rise in allele frequency. It is much more difficult to tell what the mechanism of selection was - sexual selection can work just like selection based on more synthesis or less degradation of vitamin D3. Social selection could have played a part, but biology isn't trivial. They're not being politically correct - they're being scientific.

"Natural selection" is the somewhat unfortunate term chosen by Darwin to distinguish it from artificial selection, which is conscious choice. People have been getting confused by it ever since. Genetically based differential reproduction would be a better general designation I think. When you've shown that the allele frequency has risen faster than it could by chance, then the hard question comes of what the mechanism was.

Is it artificial selection when we choose a mate? We're not usually trying to insure the fittest offspring the way a breeder does. The distinction between biology and social selection sort of becomes fuzzy, since our mating preferences are surely partly genetically determined.

[Armando]

"Most of us think of Europe as the ancestral home of white people. But a new study shows that pale skin, as well as other traits such as tallness and the ability to digest milk as adults, arrived in most of the continent relatively recently. The work, presented here last week at the 84th annual meeting of the American Association of Physical Anthropologists, offers dramatic evidence of recent evolution in Europe and shows that most modern Europeans don’t look much like those of 8000 years ago."

This is nonsense as the Motala 12 SHG were all pale skinned.

Motala 12 is from 5898-5531 BC which is max 7,898 years ago. That is less than 8,000 years ago.

The author even mentions Motala later in the article but she also points out that not all of Europe had the white skin alleles.

"But in the far north—where low light levels would favor pale skin—the team found a different picture in hunter-gatherers: Seven people from the 7700-year-old Motala archaeological site in southern Sweden had both light skin gene variants, SLC24A5 and SLC45A2. They also had a third gene, HERC2/OCA2, which causes blue eyes and may also contribute to light skin and blond hair. Thus ancient hunter-gatherers of the far north were already pale and blue-eyed, but those of central and southern Europe had darker skin."

LBK, Stuttgart, Germany 7,500 ybp, gedmatch F999916
pale skin rs1426654 AA

7,500 ybp is also less than 8,000 years ago.

Take a look at page 11 of the document. You'll see that modern populations are different from Swedish Hunter Gatherers and from Yamnaya. Modern people have a mix of the alleles that existed separately in those two populations.

[1798]

Motala 12 is from 5898-5531 BC which is max 7,898 years ago. That is less than 8,000 years ago.

The author even mentions Motala later in the article but she also points out that not all of Europe had the white skin alleles.

"But in the far north—where low light levels would favor pale skin—the team found a different picture in hunter-gatherers: Seven people from the 7700-year-old Motala archaeological site in southern Sweden had both light skin gene variants, SLC24A5 and SLC45A2. They also had a third gene, HERC2/OCA2, which causes blue eyes and may also contribute to light skin and blond hair. Thus ancient hunter-gatherers of the far north were already pale and blue-eyed, but those of central and southern Europe had darker skin."



7,500 ybp is also less than 8,000 years ago.

Take a look at page 11 of the document. You'll see that modern populations are different from Swedish Hunter Gatherers and from Yamnaya. Modern people have a mix of the alleles that existed separately in those two populations.

I know that it is but it is also more than 4,500 ybp so the SNP rs1426654 is a north western European Mesolithic SNP.

[lgmayka]

Take a calculator and raise 1.01 to the 90th power (3 generations per century times 30 centuries) and see what you get.

2.45--i.e., the advantaged allele would be 2.4x as common as the disadvantaged one. That exactly proves my point 90 generations of slight biological differential advantage would leave the disadvantaged allele still quite common.

I must once again emphasize that slight biological advantage does not explain rapid fixation.

[lgmayka]

I must once again emphasize that slight biological advantage does not explain rapid fixation.

Even lactase persistence does not bestow a purely biological advantage per se so great as to explain its rapid predominance in Northern Europe and its considerable presence even in Southern Europe. After all, there are plenty of other foods to consume besides raw milk. Rather, social behavior must also have played a role, just as it does today: Once milk-drinking becomes common in a society (or at least among the privileged class), those who are lactose-intolerant are considered diseased or at least annoying, and therefore socially disadvantaged.

[Armando]

I know that it is but it is also more than 4,500 ybp so the SNP rs1426654 is a north western European Mesolithic SNP.

The portion of the article that you had quoted didn't say anything about 4,500 ybp or that it didn't exist in the Mesolithic. If your beef wasn't with what was quoted in the article why did you quote it?

Now that you have expressed what your beef is with. Why do you ignore what I quoted where they state not all of Europe had the rs1426654 SNP in the Mesolithic? Why do you ignore that page 11 of the PDF show it to be in 100% of modern populations of Italians, Central Europeans, British, and Finnish but not 100% of Mesolithic or Early and Middle Neolithic Europeans?

[1798]

The portion of the article that you had quoted didn't say anything about 4,500 ybp or that it didn't exist in the Mesolithic. If your beef wasn't with what was quoted in the article why did you quote it?

Now that you have expressed what your beef is with. Why do you ignore what I quoted where they state not all of Europe had the rs1426654 SNP in the Mesolithic? Why do you ignore that page 11 of the PDF show it to be in 100% of modern populations of Italians, Central Europeans, British, and Finnish but not 100% of Mesolithic or Early and Middle Neolithic Europeans?

Why do I get the impression that this article is about shoring up the recent paper on a massive invasion from the Steppe in to western Europe 4,500ybp?

[Armando]

Why do I get the impression that this article is about shoring up the recent paper on a massive invasion from the Steppe in to western Europe 4,500ybp?

You don't have to accept science if you don't want to. Just don't expect logical people to side with you.

[1798]

You don't have to accept science if you don't want to. Just don't expect logical people to side with you.

You will have to change your opinion whenever they find ancient R1b lines in the Isles.

[Armando]

You will have to change your opinion whenever they find ancient R1b lines in the Isles.

If they find R1b-M269 from 5,000-7,000 years ago then I will accept the science that proved it. For now, the observable data tells us that won't happen.