Looking into a crowd of people, it is easy to pick out the Northern Europeans. They tend to be pale, have lighter colored hair, and a range of eye colors. Some recent genetic studies suggest that until recently, Europeans may have been dark-skinned.
The reason this is interesting is that there has been some debate as to when Europeans became so pale. Some have argued that it happened about 40,000 years ago when people from Africa swept into Europe. Others have argued that it wasn’t until farming took a hold that pale skin became common.
Vitamin D and Too Little Sun
The difference between the two theories has to do with vitamin D and where prehistoric people could get it. There are two general sources for vitamin D—sunlight and diet.
We know that a farmer’s diet does not have enough vitamin D meaning that people in farming-based societies need to get a lot of it from the sun. We also know there is not enough sunlight in Northern Europe for dark skinned people to get enough vitamin D. So farming based societies that live in Northern Europe need to have lighter skin.
But farming didn’t really take a hold in Europe until 6,000 or 8,000 years ago. So what about the 30,000 or 35,000 years that people lived in Europe before farming? If there was enough vitamin D in their diet, then there would have been no need for pale skin. Recent genetic work suggests that the diet of these hunter-gatherers may have had plenty of vitamin D.
The Golden Gene
The gene responsible for the light skin of Europeans was found late in 2005 in a zebrafish study. The researchers found that there were two versions of the gene—a light one and a dark one. Northern Europeans are pale partly because they have two copies of the light version.
A preliminary genetic study done in the summer of 2007 by researchers at Penn State found that the light version of the golden gene may not have become common in Europe until 6000 or 12,000 years ago. Right when farming became much more common.
The obvious conclusion is that Europeans were dark until they took up farming. This would certainly be true if the golden gene were the only gene involved in skin color. But it isn’t.
Many Genes Are Involved in Skin Color
Skin color happens because of lots of different genes all working together. For example, one gene that can significantly affect skin color is MC1R. Some people with broken versions of this gene end up pale with freckles (and sometimes red hair). This is no matter what other genes besides the golden one are telling them.
So while scientists can probably conclude that 30,000 years ago Europeans were not pale because of the golden gene, they cannot conclude whether they were pale or not. To do that, they are going to have to learn a whole lot more about the genetics of skin color.
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