Only Skin Deep
(continued from previous page)
Q & A WITH NINA JABLONSKI
Q: Didn’t darker skin evolve to protect us from skin cancer?
A: Evolution favors changes that improve reproductive success. Because skin cancer usually affects people after they have had children, it likely had little effect on the evolution of skin color.
Q: Why aren’t natives of Alaska and Canada really pale? They live in places where there are long periods of complete darkness every year.
A: Native people of Alaska and Canada have darker skin than we might predict. This is for two reasons. First, in the summer they get high levels of UVR reflected from the surface of snow and ice, and their dark skin protects them from this reflected light. Second, although
their darker skin slows down the process of making vitamin D in their skin, this problem is compensated for by their traditional diet, which consists mostly of vitamin D-rich foods such as seal, walrus, and fish.
Q: What will humans look like 1,000 years from now? Will there still be many different skin colors?
A: They will still come in lots of colors, but in big cities, where many people from different places live and mix, there will be even more who have "in-between" skin colors and fewer people with strikingly dark or light complexions.
Q & A and quotes courtesy of the Science Museum of Minnesota.
|