Keep in mind, of course, that sexual selection need not have any particular “cause”. Women might just have fairer skin because men prefer women to be fairer skinned, and men might just prefer fairer skinned women because they look more feminine. Fairer skinned women look more feminine, of course, because women tend to have fairer skin than men. Yes, there might be an underlying reason (perhaps, in this case, vitamin D production), but it might also just be something that happened by chance, and once it happened was reinforced by sexual selection.
Hmmm…this might be opening an unnecessary can of worms…
But mightn’t the female tendency towards paler skin have to do with the fact that for most of history men spent a lot more time outside of shelter compared to women? The men who were the most successful hunters/gatherers/providers would have been the ones best able to withstand the sun.
Women, on the other hand, would have benefitted more from lighter skin (as mentioned several times above).
Has anyone done/seen a study as to whether or not the male/female difference in skin color is present in areas where females spent as much time out of shelter?
[John Stewart]Whaaaa?[/JS]“Famous guy sez” is generally a faulty appeal to authority argument unless you include why he said it. Also what is meant by “the modern humans?” The modern humans I know come in all colors.
Spencer Well’s studies of the Y-chromosome support the “out of Africa” theory of the origin of modern humans (Homo sapiens). Origin in an equatorial area implies that the ancestral populations would have been relatively dark-skinned. However, AFAIK actual origin in an equatorial region has not been demonstrated. If the ancestral population came from the far south of Africa, it might have been no darker skinned than modern Khoisan (“Bushmen”), who are medium brown.