In human evolution, changes in skin's barrier set northern Europeans apart

The popular idea that northern Europeans developed light skin to absorb more UV light so they could make more vitamin D -- vital for healthy bones and immune function -- is questioned by researchers in a new study. Ramping up the skin's capacity to capture UV light to make vitamin D is indeed important, however, researchers concluded in their study that changes in the skin's function as a barrier to the elements made a greater contribution than alterations in skin pigment in the ability of north...