Skin Color and Natural Selection

Penn State University anthropologist Nina Jablonski has told colleagues at the annual American Association for the Advancement of Science meeting that “The mechanism of evolution can be completely understood from skin color” and therefore “we can teach the principles of evolution using an example on our own bodies.” That is, school teachers should treat skin color as evidence of evolution and portray it as such to students.

Of course, creationists agree that differences in human skin color can be traced back to the process of natural selection. After humans were dispersed from the Tower of Babel, the emigrating populations would have encountered vastly different environments. Some headed closer to the equator, some stayed in the mid-latitudes, and others headed farther north. In the process, some populations gained increased exposure to ultraviolet rays from the sun, while others (those moving north) had decreasing exposure to UV light.

UV light has both helpful and harmful effects in humans. A certain amount is required for vitamin D production, but too much can destroy folate. Dark pigmentation helps block UV light, while light pigmentation lets more radiation in. So it’s no surprise that in populations living closer to the equator, those with light-colored skin were overexposed to harmful UV effects, while darker skin offered protection. Conversely, those traveling toward the poles benefited from lighter skin, and those in the population with darker skin failed to produce enough vitamin D.

Human skin color is therefore a perfect example of natural selection, and understanding the basis for skin color differences is a strong antidote to views that wrongly make a sharp delineation between “races” (which have no basis in biology).

Human skin color is therefore a perfect example of natural selection, and understanding the basis for skin color differences is a strong antidote to views that wrongly make a sharp delineation between “races” (which have no basis in biology). But Jablonski explained, “The nice thing about skin color is that we can teach the principles of evolution using an example on our own bodies and relieve a lot of social stress about personal skin color at the same time” (our emphasis). Differences in human skin color can only be considered an example of “evolution” insofar as evolution means “change”—that the makeup of populations changed because of how skin color interacts with UV rays. It has nothing to do with molecules-to-man evolution, because no new information originates in the human genome. Otherwise, the implication would be that some humans are more highly evolved than others!

The Bible provides a foundation for understanding human history, including how human people groups branched out from Babel and how natural selection led to an increase in difference between those people groups. Sadly, racism is one reminder of this history—and for that reason, we generally shy away from even referring to different skin “colors,” since in fact all human skin is a different tone of the brown color of the pigment melanin.