Science Questions

Why are Inuit people dark skinned? Leslie Nova

We put this to Nina Jablonski

Yes, there is a great contrast. Swedes evolved lightly pigmented skin and light eyes, and due to a different set of genetic changes, people living at the same latitude, the Inuit people, in far North Eastern Asia and in Alaska have actually darker skin than we would predict, and dark hair. Now the dark skin is very interesting because they Inuit experience very, very, high levels of reflected ultraviolet radiation—long wavelength ultraviolet radiation—from the snow. So their dark skin actually protects them from this high amount of UVA radiation. Their dark hair, we’re not exactly sure, but almost certainly the dark hair of Eastern Asian Peoples was a consequence of small population effect; the genetic drift in the ancestors of all East Asian Peoples.

Chris Smith:  So Nina, with that in mind, do you also see increased pigmentation or re-pigmentation amongst seafaring people, because of course they’ll get the incident radiation off the water surface?

Nina Jablonski: Yes, and in many of these seafaring peoples are naturally very dark and they have an excellent potential for making more pigment in their skin. So yes, we need more genetic studies of these people so that we can better understand how their pigment systems work.

May 2009