Imagine a world where everyone had brown skin. Tens of thousands of years ago, that was the case, say scientists at Penn State University. So, how did white people get here?
Evidently, when humans began leaving Africa 20,000 to 50,000 years ago, a skin-whitening mutation appeared randomly in a sole individual. That mutation proved advantageous as humans moved into Europe. Why? Because it upped the amount of vitamin D the migrants had.
"Sun intensity is great enough in equatorial regions that the vitamin can still be made in dark-skinned people despite the ultraviolet shielding effects of melanin," explained Rick Weiss of the Washington Post. "In the north, where sunlight is less intense and cold weather demands that more clothing be worn, melanin's ultraviolet shielding became a liability, the thinking goes."
The Penn State researchers also found that Asians developed light skin because of different genetic mutations. So, what does this mean? Have scientists identified a race gene? Hardly. As the Post notes, the scientific community maintains that "race is a vaguely defined biological, social and political concept, ... and skin color is only part of what race is--and is not."
As I've explained in my "What Is Race?" piece on the Race Relations site, scientists still say that race is more of a social construct than a scientific one because people of the so-called same race have more distinctions in their DNA than people of different races do. In fact, scientists posit that all people are roughly 99.5 percent genetically identical.
The Penn State researchers' findings on the skin-whitening gene show that skin color amounts for a miniscule biological difference between humans.
"The newly found mutation involves a change of just one letter of DNA code out of the 3.1 billion letters in the human genome--the complete instructions for making a human being," the Post reports.
Still, scientists and sociologists fear that the identification of this skin-whitening mutation may lead people to argue that whites, blacks and others are somehow inherently different. Keith Cheng, the scientist who led the team of Penn State researchers, wants the public to know that's not so. He told the Post, "I think human beings are extremely insecure and look to visual cues of sameness to feel better, and people will do bad things to people who look different."
His statement captures what racism is in a nutshell. Truth be told, people may look different, but there's virtually no difference in our genetic make up. Skin color really is just skin deep.