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Black skin is supposed to have evolved in tropical latitudes as protection against tropical UV rays. Egypt is not in the tropics. Therefore, wouldn't the black AEs have experienced relatively high levels of Vitamin D deficiency? How would they have protected themselves from it?
Posts: 7069 | From: Fallbrook, CA | Registered: Mar 2004
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quote:Originally posted by T. Rex: Black skin is supposed to have evolved in tropical latitudes as protection against tropical UV rays. Egypt is not in the tropics. Therefore, wouldn't the black AEs have experienced relatively high levels of Vitamin D deficiency? How would they have protected themselves from it?
Black skin is not supposed to have evolved, it did evolve to protect from harmful UV rays, no ifs ands or buts about it. Is white skin indigenous to any part of Africa? Would anywhere in Africa have low enough UV latitudes to make an individual pale in order to sustain Vitamin D levels? The sun may not be as intense in Egypt, but it's still Africa, everyone who is anyone, knows the desert is open land, with the sun beating right down on you so if you don't have natures sun screen (melanin) like the AE'S did, result would usually be some kind of skin cancer. Egypt is not cold, nor is a dark cloudy environment that barely lets sun through, like northern Europe. There would have been no need to be pale, therefore no Vitamin D deficiencies. If Egyptians would have moved into northern latitudes(being that AE had retained their natural melanin levels) like all humans migrating into lower UV environments/northern latitudes, without the actual sun like in Africa, is when Egyptians would've developed the need to produce Vitamin D in different ways. I.e take supplements or turn lighter in order to allow the sun to enter and produce vitamin D trough synthesis. Since as we know, melanin(natures sunscreen), blocks out the sun.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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^^^^^ Exactly Vitamin D deficiency is only found in Cold, Sun deprived places like Northern Europe and Iceland etc. The Egyptians also descend from people that "Evolved"(If you can call it that) in the lush "Tropical" environment of the Sharah before it dried up, hence they were tropically adapted.
Is this even a serious question...?
Posts: 8804 | From: The fear of his majesty had entered their hearts, they were powerless | Registered: Nov 2007
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quote:Originally posted by T. Rex: Black skin is supposed to have evolved in tropical latitudes as protection against tropical UV rays. Egypt is not in the tropics. Therefore, wouldn't the black AEs have experienced relatively high levels of Vitamin D deficiency? How would they have protected themselves from it?
There are so many levels of ignorance here, I have a hard time knowing where to start.
Some Points; Black people have inhabited areas in Siberia and Northern Europe for thousands of years - fundamentally Unchanged!
>Southern Egypt IS in the tropics, the country is not big enough to have a wide range of climates.
>You are assuming that White people turned White because of a lack of vitamin D; there is another theory which states that White people are a fixed Albino race.
Another possibility is "Vitiligo", a disorder in which pigment-making cells are destroyed. White patches appear on different parts of the body, tissues in the mouth and nose, and the retina. "There is no cause, there is no cure, and it's very random. A person could turn all the way white or mostly white."
Posts: 22721 | Registered: Oct 2005
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^ LOL @ the poster above me refering to "so many levels of ignorance" while his posts are even more so illogical!
Anyway T-rex, just to answer your question the southern most part of Egypt lies within the Tropic of Cancer making that area tropical whereas the rest of the country lies just above it making that climate subtropical. The entire continent of Africa stretches from subtropical north (just above the Tropic of Cancer) to subtropical south (just below the Tropic of Capricorn). And populations indigenous to subtropical populations still get alot of UV which is why their black skin is still useful and vitamin D deficiency is rare.
Note many light-skin peoples of North Africa, especially 'white' Berbers such as the Kabyle and Rif are highly prone to skin cancer which comes to show how much UV even the Maghreb area gets which is even farther north of the Tropic of Cancer than Egypt. Conversely, white Australians have the highest rates of skin cancer in the world and Australia is farther south of the Tropic of Capricorn than South Africa (the whites of that country by the way, have the world's second highest rates of skin cancer).
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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Humans (black, Red, Yellow, or subspecies) do not obtain their complete daily recommended Vitamin D dosage from sunlight. Vitamin D is instead obtained by a combination of sunlight and nutrition, at approx. a 40/60 ration.
Besides that point, there is no direct evidence connecting or supporting Albinism to severe Vitamin D deficiency.
Lastly, Berbers following age old precautions against skin cancer by dressing and spending fixed time in direct sunlight. Notice the dress of this Berber woman. Also note the aging from sunlight of her face. Notice also her hand which shows clear signs of advanced skin damage, very likely by solar radiation over time. It appears almost blue. Perhaps the origin of Egmond's "Blue bloods" of Europe label.
I strongly suspect skin cancers in Berbers is much higher than reported. They are not exactly a major priority for inclusion within Europe funded skin cancer studies although they may possibly be some of Africa's oldest admixed descendants of early African Albinos. Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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"black skin" what a nut. No depiction of AE's has ever shown them with black skin.
Posts: 2069 | From: Texas | Registered: Sep 2008
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Greek and Roman scholars have described Egyptians as having black "sun burnt" skin. Aren't you who professed to being a fan of the classics?
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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^ You waste your time, King. Patriot knows all about the Egyptians being black, he just can't accept it and so repeats his racist lies to himself and to others in this board. Why this board? God knows.
As for minibrainer, it has been explained to him ad-naseum that European 'white' skin is NOT albinism and that there is no such thing as a "fixed albino race" or whatever pseudo-scientific nonsense you and Marc's minions like to spin up. It's a shame that narmer doesn't realize his nonsense is even sillier than patriot. But oh well.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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See this is what I am talking about with unity. Posters working together in a civil manner to refute ignorance. This is what we need more of, stop the insults and work together. Good Job, Mike, Djehuti, and Knowledge.
Peace
Posts: 9651 | From: Reace and Love City. | Registered: Oct 2005
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There's NOTHING wrong with the AE sharing an ethnonym (black) with modern people, and they were generally yellow brown to dark brown to nearly black like most modern blacks are anyway.
With this in mind I try to stick close to what the ancients and their contemporaries thought steer clear of whatever it is that modern non-Africa (ie America/European) culture holds as black.
1)A part of modern Egypt lies in the Tropics, but most of it lies in what are called the sub-Tropics.
2)The northernmost part of Egypt is approximately 35 degrees north of the Equator.
3) All of South Africa, Lesotho, Swaziland lie are outside the tropics. Portions of Mozambique, Namibia and Botswana are also sub-tropical. In fact the southernmost part of South Africa[Cape Capetown, etc.] is about the same parallel as Alexandria--the most northern part of Egypt.
4) Alexandria is about the same latitude as Delhi, India and Phoenix, Atlanta, Dallas and El Paso in the U.S.
5) In parts of tropical Africa there are intense UV rays experienced by populations in elevated areas. Interestingly enough the locals tend to be a bit less pigmented than elsewhere: i) the Fouta areas of West Africa, ii) Ethiopian and Kenya highlands, iii) Southern Congo as in Lubumbashi, iv) Rwanda, Uganda, Burundi, v)Jos Plateau(Nigeria), vi) Swaziland[intensely cold in winter months].
Thus the climate the AEs experienced would have been no different from many parts of Africa.
One curiousity I have: what are the statistics on the incidence of melanomia with Native Americans and Australian Aboriginese? Both groups lived for thousands of years in areas that would be intensely cold during the winter months. Did they suffer from vitamin D deficiences?
Posts: 5492 | Registered: Nov 2004
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quote: One curiousity I have: what are the statistics on the incidence of melanomia with Native Americans and Australian Aboriginese? Both groups lived for thousands of years in areas that would be intensely cold during the winter months. Did they suffer from vitamin D deficiences?
Lamin I've already explained this to you. Everything has to do with locality, climate and diet. As early humans started migrating north into Europe and east into Asia, they were exposed to different amounts of sun. Those who went north found their dark skin worked against them–preventing them from absorbing enough sunlight to create vitamin D. To adapt, these humans started producing less melanin. But Early Europeans (as Inuit are today)were hunter gatherers and survived on ready sources of vitamin D from the animal and fish fats etc... that they consumed. Only when Europeans came to adopt agriculture during the(new age revolution) Neolithic revolution were their diets unable to provide them with adequate amounts of Vitamin D, since farming based societies don't produce a lot of vitamin D as a hunter gatherer who eats animal fat, and survives on 50-65% meat containing adequate amounts of vitamins. Therefore had to turn lighter to allow UV rays to enter for synthesis for production of Vitamin D. Which was only 6-8kya when farming spread into Europe. Sunlight is required to turn cholesterol into vitamin D, avoiding the sun will likewise undermine our ability to synthesize vitamin D. And since vitamin D-rich foods are also rich in cholesterol, low-cholesterol diets are inherently deficient in vitamin D. Vitamin D is best known for its role in calcium metabolism and bone health, but new roles are continually being discovered for it, including roles in mental health, blood sugar regulation, the immune system, and cancer prevention. Skin produces vitamin D when hit by ultraviolet light in sunlight. The amount depends on where people live, skin pigment, age and other factors. Dark-skinned people, and anyone living in northern latitudes, make far less than some other groups. Therefore darkskinned populations living in northern latitudes are more at risk for diseases such as many forms of cancer, high blood pressure, depression, and immune-system disorders such as multiple sclerosis, rheumatoid arthritis and diabetes. Inuit vitamin D intake wasn’t dependent upon the sun. They get all that they need from their diet, heavy on types of fatty fish that are naturally rich in vitamin D. The plentiful amounts of the vitamin kept them from developing less melanin. In fact, before milk was fortified with D, people living outside of Northern Canada and Alaska loaded their diets with fishy products, such as cod liver oil, to get their daily supplement. So despite their chilly climate and lack of sun exposure, it’s the Inuit diet that has kept them in their natural glow. These natives, if diets are changed from their traditional diets, develop different diseases. A hunter gatherers diet provides adequate amounts of Vitamin D from animal fats, fish etc... Areas were only settled if these resources were available. Native Americans diet consisted of 50-65% meat. Most Native Americans and Australian Aborigines, like Inuit, are/were hunter gatherers. The diets of the American Natives varied with the locality and climate but all were based on animal foods of every type and description, not only large game like deer, buffalo, wild sheep and goat, antelope, moose, elk, caribou, bear and peccary, but also small animals such as beaver, rabbit, squirrel, skunk, muskrat and raccoon; reptiles including snakes, lizards, turtles, and alligators; fish and shellfish; wild birds including ducks and geese; (for Indians living in coastal areas); insects including locust, spiders and lice; and dogs. (Wolves and coyotes were avoided because of religious taboos).
Before white settlement, Aboriginal people were hunter-gatherers who foraged for uncultivated plants and hunted wild animals. The traditional diet was high in carbohydrates, protein and nutrients, and low in fat and sugars. It seems that diet-related diseases, such as cardiovascular disease and diabetes, were uncommon. However, modern Aboriginal diets are heavily Westernised and tend to be high in fat and sugar, but low in carbohydrate, fibre and nutritional value. The rate of cardiovascular disease and diabetes is now exceptionally high in the indigenous population.
Traditional diet or bush food The typical traditional diet was low kilojoule and high in carbohydrate, fibre, protein and nutrients. Since Aboriginal people were hunter-gatherers, the daily diet varied according to the type of plants and animals available in the particular location and season. By necessity, they had an extensive knowledge of plants, animals, the land and the effects of the weather and time of year. Popular energy-dense foods, or foods that contained plenty of kilojoules per gram, included animal meat and offal, honey, and insects such as witchetty grubs. Women tended to gather the foods for everyday eating such as plants, reptiles and honey, while men hunted for land and marine animals. Most foods were eaten raw, but some were roasted or baked. Children were typically breastfed until three years of age, and introduced to solid foods once their teeth had come through. The hunter-gatherer lifestyle also meant plenty of physical activity.
Dietary changes during white settlement Once the Europeans arrived, the traditional Aboriginal diet shifted to include Western foods such as flour, sugar and processed meat. Indigenous people on cattle stations or government settlements had fewer opportunities to forage for food, and tended to rely more and more on European staples. The typical Aboriginal diet started to lack essential nutrients. Protein, vitamin and mineral deficiencies were common. European settlement meant the introduction of animals and plants foreign to Australia, reduced access to land and an increase in bush fires, which further hindered the indigenous people’s ability to gather and hunt for food in traditional ways.
Modern-day diet and nutrition The typical Aboriginal diet today is high kilojoule, low in nutritional value, and high in fats and sugar. There is no need to hunt and forage for food, so physical activity levels are generally low. Surveys show that urban-dwelling indigenous people eat more fast food and salt than non-indigenous people. Living in remote outback communities reduces the range of foods available, particularly fresh fruit and vegetables. Indigenous people of the Northern Territory consume more sugar, white flour and carbonated soft drinks than the Australian average. The typical modern Aboriginal diet, whether city or country, is especially low in vitamin C, calcium and magnesium.
Diet-related diseases Diet has been linked to a number of diseases and disorders among the Australian indigenous population, including:
* Cardiovascular disease * Diabetes * Overweight and obesity * High blood pressure * Some cancers * Circulatory diseases * Stroke.
For centuries, Inuit living in Canada's Arctic spent months without sunlight, and lifetimes wearing thick, fur clothing that blocked the sunlight from their dark skin.
Mother Nature provided vitamin D in other ways. Instead of making it through sun exposure, the Inuit got a healthy dose from traditional foods that happen to be rich in vitamin D: the skin of Arctic char; seal liver; the yolks of bird and fish eggs; and seal, walrus and whale blubber.
But as the Arctic has changed, so have eating habits. While seal and char (trout) are still staples in Nunavut's isolated communities, walrus and whale consumption have been in decline for 30 years.
The result is ****vitamin D deficiency***, which surfaces as ***rickets*** , a disease most Canadians might be surprised to hear still exists in Canada. Thirty-one new cases of rickets were discovered in the first five years of Nunavut's creation.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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Much of what you posted seems highly speculative. After all, Europe is practically surrounded by the sea--and the British Isles are not only geographically small--and the places like Norway and Sweden are noted for their long traditions in fishing. The Norsemen{Vikings] who invaded the British Isles were well-knowm seafarers. Spain France and most of Western Europe, in fact have easy access to the sea for fishing, so the thesis as to why Europeans are depigmented is easily questioned.
Also there are many rivers in Europe where fishing was much engaged in. Sardines, cod, salmon, perch, fish eggs[caviar, etc.] etc. have always been part of European diets. So let us look for why they lost their pigmentation elsewhere.
Posts: 5492 | Registered: Nov 2004
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1)A part of modern Egypt lies in the Tropics, but most of it lies in what are called the sub-Tropics.
2)The northernmost part of Egypt is approximately 35 degrees north of the Equator.
3) All of South Africa, Lesotho, Swaziland lie are outside the tropics. Portions of Mozambique, Namibia and Botswana are also sub-tropical. In fact the southernmost part of South Africa[Cape Capetown, etc.] is about the same parallel as Alexandria--the most northern part of Egypt.
4) Alexandria is about the same latitude as Delhi, India and Phoenix, Atlanta, Dallas and El Paso in the U.S.
5) In parts of tropical Africa there are intense UV rays experienced by populations in elevated areas. Interestingly enough the locals tend to be a bit less pigmented than elsewhere: i) the Fouta areas of West Africa, ii) Ethiopian and Kenya highlands, iii) Southern Congo as in Lubumbashi, iv) Rwanda, Uganda, Burundi, v)Jos Plateau(Nigeria), vi) Swaziland[intensely cold in winter months].
Thus the climate the AEs experienced would have been no different from many parts of Africa.
Correct. The tropical zone is that part of the globe lying within the two latitudinal tropic lines-- the tropic of cancer in the north and the tropic of capricorn in the South, with the equator lying right between them. The equator or equatorial zone is the part of the globe that recieves the most sunlight so is therefore the hottest. The closer you get to the equator, the more sunnier it is and the hotter it is. The farther away, has the opposite effect.
^ Notice, the vast majority of Africa lies within the tropics while only portions of the continent stick out. The areas lying just outside of the tropical lines are therefore in the subtropics, which still recieves quite a substantial amount of UV.
^ Notice where modern Egypt is relative to the tropics. Interestingly, that area of modern southern Egypt was in ancient times Lower Nubia, but it is irrelevant in that even northern Egypt which was subtropical still recieved plenty of UV. (Unless idiots like 'Patriot' want to argue that blacks were somehow confined to the tropics and that the tropic of Cancer was a barrier LOL)
quote:One curiousity I have: what are the statistics on the incidence of melanomia with Native Americans and Australian Aboriginese? Both groups lived for thousands of years in areas that would be intensely cold during the winter months. Did they suffer from vitamin D deficiences?
Actually Native American populations are much more recent to their home in the Americas than the Australian Aboriginals. The Aborigines have been living in Australia for 50,000 years or more whereas as Native Americans by and large arrived in the Americas over 15,000 years ago. The Aborigines descend from a population that have never left the tropics and so were always black compared to the ancestors of the Native Americans who were lighter skin people who reached the Americas from Siberia. Of course I'm excluding the Paleo-Americans like Luzia.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by lamin: Much of what you posted seems highly speculative. After all, Europe is practically surrounded by the sea--and the British Isles are not only geographically small--and the places like Norway and Sweden are noted for their long traditions in fishing. The Norsemen{Vikings] who invaded the British Isles were well-knowm seafarers. Spain France and most of Western Europe, in fact have easy access to the sea for fishing, so the thesis as to why Europeans are depigmented is easily questioned.
Also there are many rivers in Europe where fishing was much engaged in. Sardines, cod, salmon, perch, fish eggs[caviar, etc.] etc. have always been part of European diets. So let us look for why they lost their pigmentation elsewhere.
This is correct. The, European turning Albino theory, championed by Europeans is very dubious, and not repeated anywhere else on earth, making it also, a very rare occurrence of environmental adaption. There are other cultures within and outside of Europe who have experienced long term Vitamin D deficiencies, and none of them have turned pale enough to share Albinism symptoms. Unless, of course, they were Albinos which occurs in every known species on earth. There is no forensic or example evidence backing these European "evolution" theories.
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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Usefull pic . Then following your logic. The people on the southern tip of Africa are in a similar environmental condition as north Africa. They are about 10deg lat south/north of the "tropics".
Do they have the same phenotype?? ie the indegnous people that is. And why not? Come on answer that followup question.
quote:Originally posted by Djehuti:
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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^ That depends on what you mean by phenotype. If you mean skin color, then yes the indigenous peoples of Southern Africa and Northern Africa share the same range of complexions from yellowish brown to dark brown. And interestingly enough I've seen pictures of North African indigenes who look strikingly similar to Khoisan in terms of some features.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by meninarmer: This is correct. The, European turning Albino theory, championed by Europeans is very dubious, and not repeated anywhere else on earth, making it also, a very rare occurrence of environmental adaption. There are other cultures within and outside of Europe who have experienced long term Vitamin D deficiencies, and none of them have turned pale enough to share Albinism symptoms. Unless, of course, they were Albinos which occurs in every known species on earth. There is no forensic or example evidence backing these European "evolution" theories.
That's because Europeans never "turned albino", nitwit! 'White' Europeans are again for the dozenth time NOT the result of albinism and NO sane person with the slightest bit scientific knowledge thinks European' paleness is the result of albinism.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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^ There were no European Albinos because they were all African Albinos, Artificial Intelligence.
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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Tell me why do you think some northeast Asian people like the woman below have pale skin?
Is this the result of albinism as well??
And my intelligence by the way is very real unlike yours, NO intelligence.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: ^ No. They are not albinos at all, fool.
Tell me why do you think some northeast Asian people like the woman below have pale skin?
Is this the result of albinism as well??
And my intelligence by the way is very real unlike yours, NO intelligence.
LOL, fool. She has pale skin due to the origins of her peoples through admixture and environmental adaption. Still, next to Europeans, Asians are second in leading the world in susceptibility in Skin Cancer and melanoma. What's your point?
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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Interesting point though: Europeans have never referred to East Asians as "white"--always "yellow"--as in "Yellow Peril". Or during their wars with East Asians, it was always "yellow bastards"--and the like.
So it seems that according to what the Europeans saw up close, East Asians were mainly olive coloured of pigmented as the the Khoisans are.
Matters are compouned by the fact that East Asian eye colours are rarely "non-brown/black" and the same for the hair which is invariably solid black.
Posts: 5492 | Registered: Nov 2004
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quote:Originally posted by lamin: Much of what you posted seems highly speculative. After all, Europe is practically surrounded by the sea--and the British Isles are not only geographically small--and the places like Norway and Sweden are noted for their long traditions in fishing. The Norsemen{Vikings] who invaded the British Isles were well-knowm seafarers. Spain France and most of Western Europe, in fact have easy access to the sea for fishing, so the thesis as to why Europeans are depigmented is easily questioned.
Also there are many rivers in Europe where fishing was much engaged in. Sardines, cod, salmon, perch, fish eggs[caviar, etc.] etc. have always been part of European diets. So let us look for why they lost their pigmentation elsewhere.
Are you seriously that slow? Europeans were affected by agriculture, they didn't retain melanin by just eating fish. They survived on a hunter gatherers diet which consists of many animal fats, fish etc... sometimes over 50% meat is in a hunter gatherers diet. When Europe adopted agriculture they(which was during the Neolithic revolution) they stopped hunting and gathering their foods, no more animal fats/meats, no more excess fishing as there was before, that they were totally dependent on. When agriculture spread Europeans did not have to hunt anymore for their foods. Inuit are a perfect example of a hunter gatherer population consuming extremely high levels of vitamin D in their diets, show me where modern European diet is even close to the Inuit diet when it comes to the consumption of Vitamin D? Inuit will also develop vitamin D deficiencies if they stop eating their highly enriched vitamin d diet. Inuit **need** to consume this daily and they do, and a lot of it. Europeans don't eat the hunter gatherers diet as Inuit, or their early European ancestors did.
There are 6 or more genes selected 6-8kya, which is actually in alignment with the spread of agriculture, and is in alignment with Europeans skeletons not being lactose intolerant 5kya, which means they didn't adapt or were just adapting this tolerance as they took up dairy farming. And Inuit are clear example of a hunter gatherers population living in harsh extremely cold environments and still retaining melanin. Scientific fact proves Inuits retain melanin due to high vitamin d intake due to their hunter gatherers diet, and if switched will develop Vitamin D deficiency since melanin blocks out the ability to absorb UV. Scientific facts shows pale skin can absorb more UV rays under darker skies and can produce this synthesis of UV into Vitamin D.
quote: "There is ample evidence that selection has been a major driving point in our evolution during the last 10,000 years, and there is no reason to suppose that it has stopped," said Jonathan Pritchard, a population geneticist at the University of Chicago who headed the study.
Dr. Pritchard and his colleagues, Benjamin Voight, Sridhar Kudaravalli and Xiaoquan Wen, report their findings in today's issue of PLOS-Biology.
Their data is based on DNA changes in three populations gathered by the HapMap project, which built on the decoding of the human genome in 2003. The data, though collected to help identify variant genes that contribute to disease, also give evidence of evolutionary change.
The fingerprints of natural selection in DNA are hard to recognize. Just a handful of recently selected genes have previously been identified, like those that confer resistance to malaria or the ability to digest lactose in adulthood, an adaptation common in Northern Europeans whose ancestors thrived on cattle milk.
But the authors of the HapMap study released last October found many other regions where selection seemed to have occurred, as did an analysis published in December by Robert K. Moysis of the University of California, Irvine.
Dr. Pritchard's scan of the human genome differs from the previous two because he has developed a statistical test to identify just genes that have started to spread through populations in recent millennia and have not yet become universal, as many advantageous genes eventually do.
The selected genes he has detected fall into a handful of functional categories, as might be expected if people were adapting to specific changes in their environment. Some are genes involved in digesting particular foods like the lactose-digesting gene common in Europeans. Some are genes that mediate taste and smell as well as detoxify plant poisons, perhaps signaling a shift in diet from wild foods to domesticated plants and animals.
Dr. Pritchard estimates that the average point at which the selected genes started to become more common under the pressure of natural selection is 10,800 years ago in the African population and 6,600 years ago in the Asian and European populations.
Dr. Richard G. Klein, a paleoanthropologist at Stanford, said that it was hard to correlate the specific gene changes in the three populations with events in the archaeological record, but that the timing and nature of the changes in the East Asians and Europeans seemed compatible with the shift to agriculture. Rice farming became widespread in China 6,000 to 7,000 years ago, and agriculture reached Europe from the Near East around the same time.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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But the East Asians are relatively fair in complection and we know them to be great sea-food eaters--all the vitamin D they could ever want.
I want to put aside all thsoe fancy theories thrown up by the speculators.
Use Occam's Razor: People who lived for thousands of years in colder climates eventually lost their tropically adaptive pigmentation because they no longer needed it.
Something like that happened when the primate ancestors of humans lost their tails--because they were no longer needed. The old adage is fine with me: use it or lose it!
Posts: 5492 | Registered: Nov 2004
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quote:Use Occam's Razor: People who lived for thousands of years in colder climates eventually lost their tropically adaptive pigmentation because they no longer needed it.
Exactly, when humans move north into colder climes there is no need to be dark skinned, since dark skin was evolved to protect from the sun, it also blocks the ability to synthesize UV for production of Vitamin D. Now, as explained as explained(Inuits are clear example) if a humans diet is heavy in this Vitamin D intake then there would be no need to be pale, since pale skin is evolved to allow UV rays to get to the skin for production of Vitamin D. Another clear example are any darkskinned populations living in northern latitudes. Skin produces vitamin D when hit by ultraviolet light in sunlight. The amount depends on where people live, skin pigment, age and other factors. Dark-skinned people, and anyone living in northern latitudes, make far less than some other groups with pale skin, and therefore darkskinned populations(if not receiving adequate amounts from their diet or sun) are recommended to take Vitamin D supplements in northern latitudes.
THE COLOR IN BONES - WHY BLACK WOMEN ARE AT HIGHER RISK (In northern Latitudes)
quote:A variety of factors can cause calcium and vitamin D deficiency in African-American women. *****The high melanin content in darker skin reduces the skin's ability to produce vitamin D from sunlight.**** ****In fact, experts note that people with darker skin may need 20 to 30 times as much exposure to sunlight as fair-skinned individuals to generate the same amount of vitamin D.****** Inadequate intake of vitamin D in diet is another factor. Studies confirm that African Americans consume the lowest amounts of vitamin D from food alone among different ethnicities. According to the National Institutes of Health (NIH), as many as 75 percent of African Americans are lactose intolerant, possibly further limiting the consumption of calcium and vitamin D fortified dairy products.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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True, when facing a more severe environment with lower UV exposure, humans will adapt to their environments to receive more UV by lessening skin melanin density. This has been shown with INUITS, Siberians, Native Americans, South Americans, Indians, etc....
However, the body's natural immunization and integral part of this process will play a role in this regulation (Feedback) and halt the decrease in melanin density BEFORE it can compromise the integrity of the system. Thus, avoiding radiation damage due to excessive radiation exposure, as is true with Asians, Native Americans and INUITS, and why they do not contract skin cancers in their native environments. This is not true with Europeans whose immunization systems have been compromised at the same level as those suffering from, Albinism, thereby making them as susceptible to skin cancers, even in their native environments.
This has nothing to do with Vitamin D acquisition or deficiency, and has everything to do with genetic defect, as in Albinism.
Else, you can disprove this theory but presenting research showing how Vitamin D deficiency can and has led to severe disruption of melanin production where production rate decreases exceeds and crosses the Regulation/Immunization threshold. This threshold is where European meets Albino melanin densities. It's safe to say, with the exception of intergroup Albinism, no other cultural group in the world has crossed this immunity safeguard.
Of course you cannot provide this information and will likely respond with more black woman vitamin studies which have absolutely nothing to do with the usually high skin cancer rates in whites, or blame it on the food, which also has nothing to do with skin cancer susceptibility.
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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^^^Another redundant idiot, who doesn't understand that Inuit only retain melanin levels due to the consumption of their hunter gatherers diet which happens to be rich in vitamin D.
Fact:Man evolved in the hot African sun as black, to be able to protect themselves from the harmful UV rays, man walked OOA(Out Of Africa) black, as we can see from Oceanic's(Australians, Melanesians etc..). But when humans move into northern latitudes without the intense sunrays, darkskin is a disadvantage since it blocks out the ability to synthesize UV. Under lower UV environments skin has to be lighter to be able to let in UV to allow production of Vitamin through synthesis. This is what pale skin evolved for.
Fact: Pale skin doesn't have to evolve if there is enough Vitamin D in ones diet to allow the melanin levels to stay strong. Clear example of a human population retaining pigmentation under harsh low UV environments are Eskimos due to their hunter gatherer diet which provided adequate amounts of Vitamin D.
Fact: Skin produces vitamin D when hit by ultraviolet light in sunlight. The amount depends on where people live, skin pigment, age and other factors. Dark-skinned people, and anyone living in northern latitudes, make far less than some other groups with pale skin, and therefore darkskinned populations(if not receiving adequate amounts from their diet or sun) are recommended to take Vitamin D supplements in northern latitudes.
It has nothing to do with skin cancer levels, as pale skin was not adapted to protect from the harmful sunrays, you jackass!!!! Darkskin was evolved to protect from the sun. It has everything to do with living in northern latitudes and needing to be able to produce Vitamin D in other ways. Plain and simple.
You're debunked as always. Nothing new.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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posted
^ Your logic is flawed. INUITS represent NORMAL environmental adaption in an UV environment similar to the European environment. They had the same access to the same food stuffs the Europeans did, yet maintained skin color to protect against radiation damage. Keep thinking, and one day it will, CLICK.
Posts: 3595 | From: Moved To Mars. Waiting with shotgun | Registered: Dec 2006
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quote:Originally posted by meninarmer: ^ Your logic is flawed. INUITS represent NORMAL environmental adaption in an UV environment similar to the European environment. They had the same access to the same food stuffs the Europeans did, yet maintained skin color to protect against radiation damage. Keep thinking, and one day it will, CLICK.
^^^Really? Show me where Europeans have retained their hunter gatherer status as Inuit do?
Please show me where Inuit farm like Europeans, and when they adopted agriculture like Europeans did?
Inuit are still hunter gatherers, and did not adopt agriculture like Europeans did. Show me where in the arctic there is a farming society with domesticated cows, goats, growing wheats, grains etc...??? Show me Inuit who are lactose tolerant? Show me Inuit that can change their traditional diet without developing Vitamin D deficiencies, such as rickets?? I'll show you many cases of Inuit eating "westernized" foods(changing their traditional diets) and developing rickets etc...
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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posted
The Laplanders(Sami) from Scandinavia are viewed by other Scandinavians as practically nomadic, living mainly off their herds of reindeer. Traditionally they have not had a settled life and have not engaged in agriculture.
Posts: 5492 | Registered: Nov 2004
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quote:Originally posted by lamin: The Laplanders(Sami) from Scandinavia are viewed by other Scandinavians as practically nomadic, living mainly off their herds of reindeer. Traditionally they have not had a settled life and have not engaged in agriculture.
The Sami did adopt agriculture as well, and they possess the genes associated under recent selective pressure as all other Europeans. Although the Sami hunted reindeer from the earliest times and kept them in small numbers as pack and decoy animals, full-scale nomadism with large herds began only a few centuries ago. The reindeer-herding Sami lived in tents or turf huts and migrated with their herds in units of five or six families, supplementing their diet along the way by hunting and fishing.
Empirically we know that not all extreme northern peoples are pale; the circumpolar peoples for example are relatively swarthy by Northern European standards. Even within Scandinavia the Sami, the indigenous people of the far north, are darker, on average, in coloring (manifest in eye and hair, though these have some correlation with skin reflectance as there are common genes underlying various pigmentation traits).
quote:Originally posted by meninarmer: LOL, fool. She has pale skin due to the origins of her peoples through admixture and environmental adaption. Still, next to Europeans, Asians are second in leading the world in susceptibility in Skin Cancer and melanoma. What's your point?
ROTFL
My point is you obviously don't know what the hell you are talking about! Northeast Asians are pale for the same reasons that Europeans are and again it has NOTHING to do albinism but part of what you said-- adaptation as well as some mutation.
Posts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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Knowledge, let's remember what the topic of this thread is-- human vitamin D production from UV exposure in Egypt. Let's not let minibrainer drag us into another sensless argument about the origins of European whiteness. The fool knows his arguments are b.s. which is why he chooses to run around the FACTS instead of answer them.
LOL at his comment about whites "never addressing albinism" yet in several other threads that have debunked him all of our sources on albinsim came from whites, even his own source from the WHO and non of them did it was European whiteness is the result of albinism! LMAOPosts: 26243 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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. Then following your logic. The people on the southern tip of Africa are in a similar environmental condition as north Africa. They are about 10deg lat south/north of the "tropics".
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