A more permanent, protective pigmentation develops over the period of several days after we have been out in the sun. This perhaps has a similar purpose, since it does not protect hereditary material in the skin very well, whereas the skin colour we are born with does. Skin colour has two balancing effects.
Dark skin absorbs most light before it reaches the hereditary material. Africans appear dark, while we appear light. But in the area of ultraviolet radiation, the opposite is true.
We have recently discovered that UV, which makes vitamin D, is spread and reflected less from light than from dark skin!
So evolution has brilliantly arranged that light skin, in regions lacking sun, absorbs more UV for the production of Vitamin D than dark skin. This is because pigment grains are more plentiful and larger in black than in white skin, and they are also distributed differently in the layers of the skin.
Healthy people need folates. But cancer cells also need folates, and one form of treatment is based on reducing the effect of folates through medication. High-intensity solar radiation likely functions as one such medication. A number of branches of science have collaborated to illustrate how skin colours have developed, as well as the role they play.
Key terms are vitamin D production in areas with little sunlight and few malignant skin diseases, and the breakdown of important substances in the blood in sunny regions. Skin colours show how important this is. They change according to sun conditions.
He does research on skin cancer, Vitamin D and health and photodynamic therapy. She does research on folates, Vitamin D, skin colours and photodynamic treatment of cancer.
Managing editor, DoP. Main navigation jump Main content jump Contact information jump. Main navigation Search our webpages Search. Back to uio. Why Skin Colours Differ Why do some people have dark skin while others have light-coloured skin? Illustration: Colourbox. Published Mar. E-mail this page Share on Facebook Share on Twitter. Department of Physics. So white people never consumed fish?
How do you explain dark skinned south Africans and dark south Americans not very far from Antarctica? The notion that a seafood diet plays into this is absurd when you consider the high seafood intake thus dietary Vit D of many very light skinned people British Isles, Scandinavia, etc.
This article, although interesting, shows that what science is trying to tell us, is in itself unscientific.
And that Inuits have retained said color from eating a rich vitamin D diet. Fair enough, until you start to think about it logically. So logically speaking, Scandinavians equally have a fish diet. And are, well… White. Also it does not answer the question of, after years plus, of white Europeans living in hotter climates, why have they not naturally become darker over this period of time.
Europeans still have European white babies, still have little to no natural protection from skin cancer, and the list could go on. All in all the math, theory and science does not add up. Is this assuming that there was on type of ape? Today we have different colored ape species today…. Are there any ape species that live in some form of dwelling to shelter?
Are there any animals that live in caves? We can only draw on things relative to our environment to form a cohesive hypothesis which ultimately form forms a concrete conclusion. When white people go skiing they come back with a tan, similar shade to inuits.
Their inuits skin colour is needed for the environment they are in. Colder climates will produce lighter skins and climates with reflective snow or lots of sun will produce darker skins. Sometimes quickly due to gene mutation. Other environmental factors need to be taken to account, diet, the use of sunscreen, number of holidays abroad, the seasonal changes and the location of close ancestors. But race is not dependant on the type like a breed of animal, but is tied to the location and location of your ancestors.
When traced back, we all come from one place. I think something people are missing a lot in the comments when comparing the Inuit and Northern Europeans is how agriculture affected Northern Europeans.
The Inuk diet relied a lot more on wild game than Northern Europeans do. From my understanding many Inuk groups rely completely on wild game. Do Northern Europeans fish? Yes, but they also farm a lot more than the Inuit do and over generations this has had an impact. If anything the argument would be best put against the Inuit and the Sami, who do have a diet that is more dependent on wild game.
Looking at some older pictures of Sami people you can see that some had darker complexions. I recommend looking at Gibbons to see more about the theory. Honestly it makes a lot of sense to me. I cannot believe that in all this discussion, there is not one comment which shows any real facts.. It seems like the light skin hypothesis from generational sun exposure and the need for humans to produce Vitamin D has some merit. Reading some added hypothesis in the comments was helpful and some of it logical.
The exposure to sunlight in arctic barren landscapes may very well be higher than in heavily forested regions in the same latitude. Do UV rays reflect up again from white snow? That would be good to know. How long does it take for white skin or darker to develop in a mass of people?
There are other physical differences in the facial structure and perhaps other minor body structures between certain groups of people generally, sub Saharan, Indian sub continent, Aborigine, from higher Himalayan regions closer to the sun and Scandinavians for example. How long did it take for all of these minor physical structures to develop? It has to be recognized how mass migrations and territorial incursions mixed up a lot of genetic traits between indigenous and new arriving populations.
How often were these regional traits generationally passed on and how long did it take to redevelop in a newly populated region where masses of people migrated to?
Maybe mankind wandered out of or developed in more than one place. It may have happened much earlier in history than we currently think and it may take much longer for these traits to show in populations. Science should always be open to questions and even questioning what is considered to be set. Since the world is now so interconnected and many more people move around so often and mixture of genetic indigenous traits if happening much more often, our future evolution may come from other factors than regional habitat.
I get the idea that to produce more Vitamin D without any equivalent food intake, sunlight taken in through the skin is required to help produce it.
Lighter the skin means more sunlight gets in. Makes perfect sense, and impossible to argue with. As I am fair skinned and burn easily, this is undeniable. However, what I am not getting is that Scandinavians always ate a lot of fatty fish I am of part Norwegian decent … Atlantic Cod anyone? Viking dishes going back to when they were writing their names on snow drifts were known to be full of fish.
Yet their skin is as pale white as they come, with mostly blue to some green and light browns for eye color. In perhaps another several thousand of years — without any intermarriage the Inut too may evolve lighter skin?
Who knows. I will get back to ya. However the theory as proposed in this article defies the facts. OR the Inut live under a highly depleted ozone layer… so all kinds of UV light is getting through… whatever. You can make up all kinds of theories for whatever fits your fancy our the politically correct times. Vitamin D has no bearing on skin color at all, only melanin. Dark skin is the original and white is a mutation. If albinos only mate with albinos, only albinos will be produced..
The logical premise is that the further north the lighter the skin. Scandinavians are not that far from the Artic, so Eskimos should be almost albino in comparison. It seems to me that a lot of nonsense is perpetuated simply to fit with the out-of-Africa theory — and it is just a theory. A further inconstancy with the out-of-Africa theory is why would tribes travel from suitable climates with plenty of food to the frozen wastes of the North?
Your email address will not be published. Previous Search. Life Science Inuits live in very cold climates, why do they have dark skin?
An Alaskan Inuk. Related Posts. Filed To anatomy biology Ever Wondered? Share Facebook Twitter Email. Emily V. Website Opens in new tab. Tyler says:. July 20, at am. Fingal says:. Their dark hair, we're not exactly sure, but almost certainly the dark hair of eastern Asian peoples was a consequence of small population effect: the genetic drift in the ancestors of all East Asian Peoples. Chris Smith: So, Nina, with that in mind, do you also see increased pigmentation or re-pigmentation amongst seafaring people, because, of course, they'll get the incident radiation off the water surface?
Nina Jablonski: Yes, and many of these seafaring peoples are naturally very dark and they have an excellent potential for making more pigment in their skin. So yes, we need more genetic studies of these people so that we can better understand how their pigment systems work That dark skin color is a mystery. Perhaps scientists should re-evaluate many of the pre-conceptions. Remember-scientists in the past believed that no inter-breeding occurred between the Neanderthal and modern man?
Why do we not see a connection similar in European populations that are located in areas that receive snow for large parts of the year, you would at least expect there to be similarities between these "snow dwelling populations" and there sea fairing European counterparts. Skip to main content. Earth Science. Why are Inuit people dark skinned? Part of the show Getting Under Your Skin.
CC0, Lomen Bros. Play Download. Question Why are Inuit people dark skinned? Answer We put this to anthropologist Nina Jablonski
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