Why are we white?
The common answer is that up North there is no selective pressure to keep sun-blocking melanin in the skin whereas the pale skin enhances photogeneration of vitamin D. Whitening of European skin is very recent, just 6-12 kya; http://www.sciencemag.org/cgi/content/summary/316/5823/364a
the Europeans became white only after the transition from hunting to farming. Oddly, the Neandertahls were pale skinned (and had red hair and blue eyes) without any farming.
http://www.sciencemag.org/cgi/content/summary/sci;318/5850/546
...Why did Europeans become pink even as Mongols and Inuits at the same or higher latitudes remained brown? Why did Mayas and Incas fail to become as dark brown as Africans or Melanesians of the same latitude? The Jablonski-Chaplin map predicts Native South Americans of Colombia, Venezuela, and coastal Peru to be as dark as equatorial Africans. In fact, they are not much darker than native North Americans. The map predicts the Saami of Lapland, the Inuit people of Greenland and Canada, and the Aleuts of the Bering Sea and northern Siberia to be lighter-skinned than Scandinavians. In fact, they are darker. The map predicts a band of people stretching around the globe at 55 degrees north latitude (the natives of Kazakhstan, Irkutsk, Ulan Bator, northernmost Manchuria, the Aleutians, Juneau, Hudsons Bay, and Labrador) to be as fair as Danes. In fact, they are much darker.
...European agriculture began about 10 kya in the Near East and spread to the Baltic by 5 kya. The advent of agriculture saw a dietary shift from meat to grains. This reduced dietary vitamin D intake among farming peoples and so perhaps lightened their complexions slightly via the paleness adaptation. It was probably not significant outside Europe because domestic cereals do not grow without intensive modern agricultural techniques above about 55 deg of latitude. Higher latitudes are just too cold-the growing season is too short-to let crops compete successfully with herds as food source. Consequently, even post-Neolithic high-latitude peoples continued to have a diet rich in meat (and so, vitamin D). These include the Inuit (seagoing mammals), Aleuts (fish), Saami (reindeer), Mongols (horses), and Native North Americans (bison).
...these adaptations functioned by the loss of genetic coding for dark complexion. The gene pool of the Native Americans who crossed through the Beringia bottleneck and populated the New World no longer had all the needed genes. The genetic variability subsequently available to their descendants simply did not include alleles at the five loci necessary to produce dark brown offspring. http://backintyme.com/essays/?p=4
...It is proposed that the pale skin seen in modern Europeans and Asians, are not the results of Darwinian selection; these attributes provide no survival benefits. They are instead the results of sexual selection combined with a third, previously unrecognized, process: parental selection. The use of infanticide as a method of birth control in premodern societies gave parents - in particular, mothers - the power to exert an influence on the course of human evolution by deciding whether to keep or abandon a newborn infant. If such a decision was made before the infant was born, it could be overturned in the positive direction if the infant was particularly beautiful - that is, if the infant conformed to the standards of beauty prescribed by the mother's culture...
http://xchar.home.att.net/n2a/medhyp.htm
...The problem with sexual selection is that it normally results in a trait’s strong sexual dimorphism... It has been suggested that dark complexion reduces the incidence of skin cancer, improves thermoregulation (ability to sweat), or camouflages the hunter. Others say that light skin is less at risk from cold injury. Some speculate that skin tone is merely an unselected by-product of adaptations to disease and parasites.
http://backintyme.com/essays/?p=4
So here we are, the victims of the white man's burden and the fosterlings of the millenia of inadequate diet and avitaminosis, the paleface aberrations inexplicably loved by the infanticidal mothers for not having the very camouflage which is needed for hunting, the lost souls who are genetically incapable of returning to the black, brown and beige world of our ancestors...
For what sins of our ancestors are we white?
the Europeans became white only after the transition from hunting to farming. Oddly, the Neandertahls were pale skinned (and had red hair and blue eyes) without any farming.
http://www.sciencemag.org/cgi/content/summary/sci;318/5850/546
...Why did Europeans become pink even as Mongols and Inuits at the same or higher latitudes remained brown? Why did Mayas and Incas fail to become as dark brown as Africans or Melanesians of the same latitude? The Jablonski-Chaplin map predicts Native South Americans of Colombia, Venezuela, and coastal Peru to be as dark as equatorial Africans. In fact, they are not much darker than native North Americans. The map predicts the Saami of Lapland, the Inuit people of Greenland and Canada, and the Aleuts of the Bering Sea and northern Siberia to be lighter-skinned than Scandinavians. In fact, they are darker. The map predicts a band of people stretching around the globe at 55 degrees north latitude (the natives of Kazakhstan, Irkutsk, Ulan Bator, northernmost Manchuria, the Aleutians, Juneau, Hudsons Bay, and Labrador) to be as fair as Danes. In fact, they are much darker.
...European agriculture began about 10 kya in the Near East and spread to the Baltic by 5 kya. The advent of agriculture saw a dietary shift from meat to grains. This reduced dietary vitamin D intake among farming peoples and so perhaps lightened their complexions slightly via the paleness adaptation. It was probably not significant outside Europe because domestic cereals do not grow without intensive modern agricultural techniques above about 55 deg of latitude. Higher latitudes are just too cold-the growing season is too short-to let crops compete successfully with herds as food source. Consequently, even post-Neolithic high-latitude peoples continued to have a diet rich in meat (and so, vitamin D). These include the Inuit (seagoing mammals), Aleuts (fish), Saami (reindeer), Mongols (horses), and Native North Americans (bison).
...these adaptations functioned by the loss of genetic coding for dark complexion. The gene pool of the Native Americans who crossed through the Beringia bottleneck and populated the New World no longer had all the needed genes. The genetic variability subsequently available to their descendants simply did not include alleles at the five loci necessary to produce dark brown offspring. http://backintyme.com/essays/?p=4
...It is proposed that the pale skin seen in modern Europeans and Asians, are not the results of Darwinian selection; these attributes provide no survival benefits. They are instead the results of sexual selection combined with a third, previously unrecognized, process: parental selection. The use of infanticide as a method of birth control in premodern societies gave parents - in particular, mothers - the power to exert an influence on the course of human evolution by deciding whether to keep or abandon a newborn infant. If such a decision was made before the infant was born, it could be overturned in the positive direction if the infant was particularly beautiful - that is, if the infant conformed to the standards of beauty prescribed by the mother's culture...
http://xchar.home.att.net/n2a/medhyp.htm
...The problem with sexual selection is that it normally results in a trait’s strong sexual dimorphism... It has been suggested that dark complexion reduces the incidence of skin cancer, improves thermoregulation (ability to sweat), or camouflages the hunter. Others say that light skin is less at risk from cold injury. Some speculate that skin tone is merely an unselected by-product of adaptations to disease and parasites.
http://backintyme.com/essays/?p=4
So here we are, the victims of the white man's burden and the fosterlings of the millenia of inadequate diet and avitaminosis, the paleface aberrations inexplicably loved by the infanticidal mothers for not having the very camouflage which is needed for hunting, the lost souls who are genetically incapable of returning to the black, brown and beige world of our ancestors...
For what sins of our ancestors are we white?