A remarkable study and hypothesis.
But it drives me nuts when a scientist makes a statement related to evolutionary changes that makes it sound as if an individual organism just switches off a particular characteristic:
“Once human populations migrated northward, away from the tropical onslaught of UVB, pigment was gradually lost in service of metabolic conservation. The body will not waste precious energy and proteins to make proteins that in no longer needs.”
I wholeheartedly agree.