quote:Originally posted by AGÜEYBANÁ(Mind718): A thinner nose, lips and straighter hair has already been shown and proven to you a million times over.
Those are not leptorrhine (thin) noses as found in Caucasoids. Those are mesorrhine, medium, as found in people of mixed race (Caucasoid and Negroid) or Mongoloids.
You can look up the nasal index online to see what qualifies as leptorrhine (thin), but none you posted do just by looking at them.
A thin Caucasoid nose looks like as follows -
Negroids get nowhere near this.
I would agree also with Perahu who commentated on these photos before that numerous of who you have posted have clear Caucasoid admixture.
Caucasoid genes are all across Africa. We know East Africans are more Eurasian (Caucasoid) than Sub-Saharan African (Negroid) hence they have straighter hair.
What's funny is that you accept North African Caucasoid/Eurasian admixture, but not East African... Its because without the East Africans your ''blacks are phenotypically diverse'' argument crumbles.
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quote:Originally posted by AGÜEYBANÁ(Mind718): So what's taking you so long to answer the following?
quote:Originally posted by AGÜEYBANÁ(Mind718): ^^So can one of those southwest Asian or Indian carcassoids move into Europe and intermix with you white carcassoid folk up north? Would it do well with bone marrow transplants? lol
I'd love to hear this one.
[/QB]
No.
Most Indians are not pure-blooded Caucasoid. They are a mix of Veddoid, Mongoloid, Negrito etc.
My comments on disease and bone marrow are all well backed up.
Mixed race people cannot find bone marrow or blood matches and secondly they are more prone to health risks.
Article: Bone Marrow Transplants: When Race Is an Issue
Here we have the story of a White (Caucasoid) father and an Indian mother who have a 4 year old son but he can't get a bone marrow transplant because he is mixed race.
Another article: '' Finding bone-marrow donors a problem for mixed-race patients| NowPublic News Coverage''
Nick Glasgow is sufferring from leukemia and he has not been able to find a donor yet because he is one-quarter Japanese. If he were white, he would have a nearly 90 percent chance of finding a matching bone marrow donor who could cure his leukemia
- So here we have another story of a mixed race (this time Mongoloid/Caucasoid) who cannot cure his leukemia because of his hybrid racial origins.
Its exactly the same for blood transfusions.
Bieng mixed race has serious health risks and its therefore a good thing that they are only a minority.
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No dunce, it's because in contrast to north Africans who show this admixture in the maternal gene pool and SLC24A5 derived allele East africans and others on the other hand who have thinner nose lips et..do not show the same geneflow. As noted if there were geneflow there would be the derived SLC245 allele highly present amongst these Africans you say are mixed, but it's not present. Sorry kid.
Like I said you believe a fantasy that non Africans magically passed on genes for nose and hair but not for skin complexion nor limb proportions, makes no damn sense Fool.
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quote:Originally posted by AGÜEYBANÁ(Mind718): So what's taking you so long to answer the following?
quote:Originally posted by AGÜEYBANÁ(Mind718): ^^So can one of those southwest Asian or Indian carcassoids move into Europe and intermix with you white carcassoid folk up north? Would it do well with bone marrow transplants? lol
I'd love to hear this one.
No.
Most Indians are not pure-blooded Caucasoid. They are a mix of Veddoid, Mongoloid, Negrito etc.[/QB]
What's the differences genetically between these Indians whom you classify into three different races by phenotypes?
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I will start charging you soon . . if you keep this up. This is a freebie!!! It is only so much I will do to help you out. Three times is a trend. And get off that Jablonski nonsense. Have you read Kittles, Harding et al latest study on the subject(2010?). I posted it here recently, don’t have time to repost. Now get to work. Remember I had to explain it to you when it was posted. First e1b1c , then Kittles. Next time you pay full price. Lol!
quote:Originally posted by the lioness:
quote:Originally posted by xyyman: Wassermann HP, and Heyl T - Quantitative data on skin pigmentation in South African races =====
In the Bantu, black and brown eyes occurred in all our cases. Blue or intermediately coloured eyes do, in fact, occur but are extremely rare.
DISCUSSION The results agree closely with those reported by other investigators. The female group tends to be lighter in colour than the male group in all 3 races, but this does not attain statistical significance in our study.
An opportunity occurred in this study to measure reflectance from a virtually completely depigmented patch of vitiligo in a Cape Coloured woman and from a corresponding area of normaily pigmented skin. The reflectance curves presented in Fig. 3 . . . .
====== see also . .
Relethford JH. Hemispheric difference in human skin color.
Relethford JH. Human skin color diversity is highest in sub-Saharan African populations.
Steegmann A Jr. Frostbite of the human face as a selective force.
Zihlman AL, Cohn BA. 1988. The adaptive response of human skin to the savanna.
Hiernaux J (1976) Skin color and climate in central Africa: A comparison of three populations.
Hiernaux J (1977) Long-term biological effects of human migration from the African savanna to the equatorial forest: A case study of human adaptation to a hot and
wet climate.
Huizinga J (1968) Human biological observations on some African populations of the thorn savanna belt.
Hulse FS (1969) Skin color among the Yemenite Jews of the isolate from Habban.
Jaswal IJS (1979) Skin color in North Indian populations.
Rebato E (1987) Skin colour in the Basque populations.
Wassermann HP, and Heyl T (1968) Quantitative data on skin pigmentation in South African races.
Weiner JS, Harrison GA, Singer R, Harris R, and Jopp Skin colour in southern Africa.
======
AHHH!!! The point is Europeans and all other populations outside of Africa came from a small group(subset) of Africans that left the continent. PERIOD.
Only the ignorant or disingenuous will say otherwise.
very little of the European phenotype originated IN Europe OR the Asian Steppes. Africans carry the 6-8 genetic markers that make the human skin "white". Light/white skin came from Africans. As unbelievable as it may sound. It is essentialy increase of these genetic markers that lead to white skin. Africans and Europeans have the same amount and capability for dark skin ie MC1R.98-99% each. (Kittles, Harding, Yakahama etc). It is the quantity of the OTHER genetic markers that are different.(called selective sweep/or purifying In the northern(AND SOUTHERN) hemishpere the levels of these other markers increased. Why? Read the studies.
Sorry boys, bottomline, light skin came first. Never thought I would here my-self say that.
They got their light skin AND Blue eyes from us.
Maybe the sunless, dark niches in Europe is where they refined their phenotype. Africans carry the all the genes that make Europeans. . .Europeans. That said. They are our long lost African brothers(wink).
Research has shown about 94%[commonality, identical DNA between human beings and chimpanzees, with some of the difference occurring in non-coding DNA.
quote:Originally posted by xyyman: ^ sigh!!!. . . Everytime I get out you drag me back in.
to be continued. . . .
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more. . .You owe me big time. Read the study then get back to me. Don't waste my time. . .please.
For the newbies. . .this is one of two point of view on how humans became depigmented.
Jablonski's is the 2nd which KIK and others have a hard-on for and keep quoting. In Kittles latest paper he no longer agrees with Jablonski. I am tired schooling this half-breed. No offence. LOL! I have blood relatives who are Mt-DNA hg-A
======== Review Worldwide polymorphism at the MC1R locus and normal pigmentation variation in humans Kateryna Makova a,∗, Heather Norton b a Department of Biology, The Pennsylvania State University, 518 Mueller Lab, University Park, PA 16802, USA b Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA Received 20 August 2004; accepted 16 December 2004 Available online 23 June 2005
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quote:Originally posted by xyyman: And get off that Jablonski nonsense.
Nitwit, what I said comes from Kittles and Norton, Jablonski just so happens to agree and further confirm it.
quote:Originally posted by xyyman: Africans carry the 6-8 genetic markers that make the human skin "white". Light/white skin came from Africans.
Wrong, Africans carry the genes in an ancestral state which keeps their skin dark in turn Europeans carry the alleles in a derived state which makes them white. You're slow at this.
quote:Originally posted by xyyman: Jablonski's is the 2nd which KIK and others have a hard-on for and keep quoting. In Kittles latest paper he no longer agrees with Jablonski.
Where's Kittles latest paper? Are you talking about the one he co-authored with Norton?
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This is a sample. . .now please ssssshhhh!!!! the "do not disturb sign is up". Raise your hands when you have a question. LOL!!
You dummies think that Jablonski is the see all end all on this. . . there are several views on this. READ READ then come to a conclusion. As I said Makova has the collar on this. Her hypothesis is more logical than this "food made Europeans white" nonsense by Jablonski.
===== Signatures of Positive Selection in Genes Associated with Human Skin Pigmentation as Revealed from Analyses of Single Nucleotide Polymorphisms O. Lao1,2, J. M. de Gruijter1,2, K. van Duijn1,2, A. Navarro3 and M. Kayser1∗ 1Department of Forensic Molecular Biology, Erasmus University Medical Centre Rotterdam, The Netherlands 2Departments of Biology, Netherlands Forensic Institute, The Hague, The Netherlands 3Institucio Catalana de Reserca i Estudis Avancats (ICREA), and Unitat de Biologia Evolutiva, Departament de Ciencies de la vida i de la salut, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain Summary Phenotypic variation between human populations in skin pigmentation correlates with latitude at the continental level. A large number of hypotheses involving genetic adaptation have been proposed to explain human variation in skin colour, but only limited genetic evidence for positive selection has been presented.
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You dunce, try again. That study agrees with Norton and Kittles et. al. Wow you're slow. lol They all confirm the same damn thing.
quote:Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians Heather L. Norton*,1, Rick A. Kittles
Abstract
Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical FST approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians.
Now the one you posted which is from 2007 and also has been used to actually refute your dumbass and others lol...
quote: Signatures of positive selection in genes associated with human skin pigmentation as revealed from analyses of single nucleotide polymorphisms.
Lao O, de Gruijter JM,
Abstract
Phenotypic variation between human populations in skin pigmentation correlates with latitude at the continental level. A large number of hypotheses involving genetic adaptation have been proposed to explain human variation in skin colour, but only limited genetic evidence for positive selection has been presented. To shed light on the evolutionary genetic history of human variation in skin colour we inspected 118 genes associated with skin pigmentation in the Perlegen dataset, studying single nucleotide polymorphisms (SNPs), and analyzed 55 genes in detail. We identified eight genes that are associated with the melanin pathway (SLC45A2, OCA2, TYRP1, DCT, KITLG, EGFR, DRD2 and PPARD) and presented significant differences in genetic variation between Europeans, Africans and Asians. In six of these genes we detected, by means of the EHH test, variability patterns that are compatible with the hypothesis of local positive selection in Europeans (OCA2, TYRP1 and KITLG) and in Asians (OCA2, DCT, KITLG, EGFR and DRD2), whereas signals were scarce in Africans (DCT, EGFR and DRD2). Furthermore, a statistically significant correlation between genotypic variation in four pigmentation candidate genes and phenotypic variation of skin colour in 51 worldwide human populations was revealed. Overall, our data also suggest that light skin colour is the derived state and is of independent origin in Europeans and Asians, whereas dark skin color seems of unique origin, reflecting the ancestral state in humans.
And another...
quote: The genetic architecture of normal variation in human pigmentation: an evolutionary perspective and model
Skin pigmentation varies substantially across human populations in a manner largely coincident with ultraviolet radiation intensity. This observation suggests that natural selection in response to sunlight is a major force in accounting for pigmentation variability. We review recent progress in identifying the genes controlling this variation with a particular focus on the trait's evolutionary past and the potential role of testing for signatures of selection in aiding the discovery of functionally important genes. We have analyzed SNP data from the International HapMap project in 77 pigmentation candidate genes for such signatures. On the basis of these results and other similar work, we provide a tentative three-population model (West Africa, East Asia and North Europe) of the evolutionary–genetic architecture of human pigmentation. These results suggest a complex evolutionary history, with selection acting on different gene targets at different times and places in the human past. Some candidate genes may have been selected in the ancestral human population, others in the ‘out of Africa’ proto European-Asian population, whereas most appear to have selectively evolved solely in either Europeans or East Asians separately despite the pigmentation similarities between these two populations. Selection signatures can provide important clues to aid gene discovery. However, these should be viewed as complements, rather than replacements of, functional studies including linkage and association analyses, which can directly refine our understanding of the trait.
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As I said it is only so much I can do to help you out.. .
A large number of hypotheses involving genetic adaptation have been proposed to explain human variation in skin colour,
quote:Originally posted by xyyman: This is a sample. . .now please ssssshhhh!!!! the "do not disturb sign is up". Raise your hands when you have a question. LOL!!
You dummies think that Jablonski is the see all end all on this. . . there are several views on this. READ READ then come to a conclusion. As I said Makova has the collar on this. Her hypothesis is more logical than this "food made Europeans white" nonsense by Jablonski.
===== Signatures of Positive Selection in Genes Associated with Human Skin Pigmentation as Revealed from Analyses of Single Nucleotide Polymorphisms O. Lao1,2, J. M. de Gruijter1,2, K. van Duijn1,2, A. Navarro3 and M. Kayser1∗ 1Department of Forensic Molecular Biology, Erasmus University Medical Centre Rotterdam, The Netherlands 2Departments of Biology, Netherlands Forensic Institute, The Hague, The Netherlands 3Institucio Catalana de Reserca i Estudis Avancats (ICREA), and Unitat de Biologia Evolutiva, Departament de Ciencies de la vida i de la salut, Universitat Pompeu Fabra, Barcelona, Catalonia, Spain Summary Phenotypic variation between human populations in skin pigmentation correlates with latitude at the continental level. A large number of hypotheses involving genetic adaptation have been proposed to explain human variation in skin colour, but only limited genetic evidence for positive selection has been presented.
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quote:Originally posted by xyyman: As I said it is only so much I can do to help you out.. .
A large number of hypotheses involving genetic adaptation have been proposed to explain human variation in skin colour,but only limited genetic evidence for positive selection has been presented.
Yea dunce, the genetic evidence for it was lacking now there's all the genetic evidence needed as shown...as shown to you Kittles agrees with everything I say, so next time don't use Kittles as if he agreed with you.
quote:Originally posted by xyyman: You dummies think that Jablonski is the see all end all on this. . . there are several views on this. READ READ then come to a conclusion. As I said Makova has the collar on this. Her hypothesis is more logical than this "food made Europeans white" nonsense by Jablonski.
Wow, how many times must it be told to your dumbass that Jablosnki doesn't say food made them white, yet you keep repeating this same nonsense, why, because that's the only leg you can stand on? Your own misinterpretation. lol
The study you posted even notes what's Jablosnki main point is, that skin color correlates with lattitude. You don't even know what it is Jablosnki promotes to even try to refute her.
Quote Jablosnki or anyone saying food magically made Europeans white, I'll wait.
Here I'll make it simple for you;
1) If it's solely due to latitude and sun intensity than why did it take tens of millenia for Europeans to turn white, why didn't they turn white once they reached Europe if its solely due to latitude at the continental level?
^^I dare you to answer this..
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@ Lioness. PDF did not convert properly. But you will get the theme. Read the paper.
=====
INTERNATIONAL JOURNAL OF ANTHROPOLOGY Vol. 4, n. 1-2: 61-74, 1989
Four Cameroonian populations were studied for a large set of anthropometric measurements. Three groups live in the forest (two Bantu speaking, and one pygmoid tribe) 'and the fourth one in the savanna plateau. Multivariate analysis'of 'thd'morphological features showed that the two Bantu groups have veryksimilarb ody morphology. This is interpreted to be a result-of-common genetic origin and of the fact that they inhabit the sameLenvkonment Whereas the Pygmoids segregate apart. The savanna dwellers'he morphologically equidistint from the two former groups, and when compared to other savanna peoples living in Burkina-Faso, are deen to be more similar to forest populations. Some dimatic influences-CaTbejidentified, mainly on limb proportions and nose and face dimensions. They seem to play a larger part in body differentiation than do.,nutritional and/or pathological conditions. Differences be&eenkthekforest Bantu and the savannadwellers are mostly due to a shape compdnent, whereas the Pygmoids display an overall reduction in$& Savanna highlanders also exhibit a 'size reduction, which rbults:in tۓ.ei&being more similar in shape to the Pygmies than are &elbther,groups compared. A fruitful approach to morphological differentiation must take advantage of opportunities to compare peoples sharini'thth;t"kdgenetoicr igin but having migrated to occupy contrastin$e.nvirbnments. The hypothesis is raised that a common African stock has differentiated in contrasting ecosystems.
CLASS IS OVER!!. . . . .
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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^What's taking you so long? Watch xyy run away for months now, only to come back and say the same BS again...
quote:Originally posted by AGÜEYBANÁ(Mind718):
Here I'll make it simple for you;
1) If it's solely due to latitude and sun intensity than why did it take tens of millenia for Europeans to turn white, why didn't they turn white once they reached Europe if its solely due to latitude at the continental level?
^^I dare you to answer this.. [/QB]
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@ KIK. We all know that Latitude/UV intensity is the trigger.
Still don't get it. . .the differences in the hypotheses, huh? All scholar agrees UV and melanin levels is the trigger.
They disgree on the "HOW" but agree on the "why". Damn man!!
Jablonski says the "how" is vit D ie food/diet changes due to the Neolithic revolution.
Makova said it is "natural" ie the "ancestral" state of humans. And she is talking primates. Hence her conclusion that Southern African Bantus are already depigmenting maybe even AAs aside from admixtures. That futher explains why central americans are also darker than the northerns and southerners.
Man! you are thicker than the lunatic. You owe me thrice!!!
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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You are lucky this Green Bay/Vikings game is boring. . .I can spend time on the net.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by xyyman: @ KIK. We all know that Latitude/UV intensity is the trigger.
Still don't get it. . .the differences in the hypotheses, huh? All scholar agrees UV and melanin levels is the trigger.
I agree that latitude and UV intensity play a role (there is no difference in hypothesis) but both go hand in hand, latitude and the vital need of Vitamin D in humans, as lighterskin can synthesize the absorption of UV in the body for a process that makes Vitamin D naturally, which occurs quicker than darkerskin can.
Seems to be much more scientific than what you have to say about it, which is "I don't know" lol.
quote:Originally posted by xyyman: They disgree on the "HOW" but agree on the "why". Damn man!! Jablonski says the "how" is vit D ie food/diet changes due to the Neolithic revolution.
Jablosnki agree that lattitude at the continental level plays a role, she authored a whole study with her husband. She also explains the need of vitamin D. Not only Jablosnki but also Kittles, Norton, Sforza et al...
Again, if it was solely due to latitude why did it take them tens of millenia to actually turn white? They should have turned white once not too long after reaching Europe.
To anyone with a brain, this makes clear sense that it's NOT solely due to latitude at the continental but other factors are at play which have been scientifically proven.
You can play stupid all you want, but others can learn from your stupidity.
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Why don't you actually read what Jablosnki has to say about it instead of acting like you did, which from your time here and responses you obviously didn't.
See here...
quote:Nina G. Jablonski and George Chaplin 2000
The evolution of human skin coloration
Skin color is one of the most conspicuous ways in which humans vary and has been widely used to define human races. Here we present new evidence indicating that variations in skin color are adaptive, and are related to the regulation of ultraviolet (UV) radiation penetration in the integument and its direct and indirect effects on fitness. Using remotely sensed data on UV radiation levels, hypotheses concerning the distribution of the skin colors of indigenous peoples relative to UV levels were tested quantitatively in this study for the first time. The major results of this study are: (1) skin reflectance is strongly correlated with absolute latitude and UV radiation levels. The highest correlation between skin reflectance and UV levels was observed at 545 nm, near the absorption maximum for oxyhemoglobin, suggesting that the main role of melanin pigmentation in humans is regulation of the effects of UV radiation on the contents of cutaneous blood vessels located in the dermis. (2) Predicted skin reflectances deviated little from observed values. (3) In all populations for which skin reflectance data were available for males and females, females were found to be lighter skinned than males. (4) The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis.
^Seems like you're stuck at one (1) saying "duhhhhh but where do I go now" while Jablosnki and everyone else is already on four (4).
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sigh. . . .KIK. My patience is running out. You are confusing the "how" with the "why".
QUOTE: Jablosnki says the HOW is lattitude. .
that's the "why". Look at it this way. ==
WHY did human depigment? - answer: because as humans moved north there was less UV.
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^Yes it does have to do with latitude nobody argues this in fact I've been saying this for years, but this is where you get stuck and I move forward with the science of it.
The how and why are the same in this instance.
How did they turn white?
Answer; The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis.
Why did they turn white?
Answer; The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis.
If Europeans turned white solely due to low UV levels logically it wouldn't have taken them tens of millenia do so.
Get it?
You have nothing to refute the Vitamin D synthesis explanation.
Either way you put it same conclusions, go hand in hand. You lose. Again.
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Again, if it was solely due to latitude why did it take them tens of millenia to actually turn white? They should have turned white once not too long after reaching Europe.
I would like to know what is the proof that it took tens of millenia how does anyone know they didn't turn light skinned quicker not too long after reaching Europe.
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AMERICAN ASSOCIATION OF PHYSICAL ANTHROPOLOGISTS MEETING
European Skin Turned Pale Only Recently, Gene Suggests
Ann Gibbons
PHILADELPHIA, PENNSYLVANIA-- At the American Association of Physical Anthropologists meeting, held here from 28 to 31 March, a new report on the evolution of a gene for skin color suggested that Europeans acquired pale skin quite recently, perhaps only 6000 to 12,000 years ago
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^^^ this is reasonable theory but far from being accepted by all evolutionary biologists at this point
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Tsk! Tsk. The how and the why would NEVER be the same. Did you graduate from college? I will dig out that Kittles paper I schooled you on earlier this year. Google search is not getting it. As Kittles stated in that paper there are TWO, yes TWO, conventional views on the HOW. Of course the paper I cited above says there are more than two. Nevertheless the leaders are Jablonski in one camp and Makova in the other. In that paper Kittles and his co-author is leaning towards Makova.
Just to be clear. All agree it was migration north ie latitude was the WHY. And in case you still don’t get it. Native Americans entered the Americas light skin NOT dark.
Here is an exercise for you. Correlate the time line of Native Americans entry into the Americas and THEIR Agricultural Revolution. As I said Jablonski ‘s Theory is nonsense. The problem with some of you is you read but do not entertain opposing or different views. To build a strong argument you need to read up on what the other side is saying. As usual what is popular at the time is what you parrot. Hence you and others keep coming back to that stupid Penn study.
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I will do you one better. Assuming – Native Americans entered North America dark approx 12ya. Educate us on how selective sweep occurred among this group. Keep in mind central Americans are dark while those to the north and south are light. And if you don’t know what I am talking about then get out of this discussion.
Problem with some of you, you still look at the world through European eyes. Europeans were not the only ones that depigmented. Asians did also.
quote:Originally posted by AGÜEYBANÁ(Mind718): [ Again, if it was solely due to latitude why did it take them tens of millenia to actually turn white?
.
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You and others (like many racist)need to keep up. You keep going back to that archaic Penn study. We now know that SLC24A45 is just ONE of MANY genes that impact skin color. You guys seem to have a hard on for that study . . . . .and that gene. There are several genes that impact skin color. SLC24A45 is just one of many. Europeans have a higher frequency, yes, but Asians and Native Americans have ZERO. Asians and Native Americans have a higher frequency of ASIP. Khoi-San has OCA2. Note Europeans also has high frequency of ASIP and OCA2 and other “depigmentation” genes.
Now please don’t waste my time.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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Let us get back to the hair discussion. Zaharan cited some papers I am looking into now. Lioness should follow those leads.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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Penance – Read the entire study 10 times then get back to me. . . .
Genetic evidence for the convergent evolution of light skin in Europeans and East Asians. By Norton and Kittles Norton HL, Kittles RA, Parra E, McKeigue P, Mao X, Cheng K, Canfield VA, Bradley DG, McEvoy B, Shriver MD. Source Department of Anthropology, The Pennsylvania State University, PA, USA. hnorton@email.arizona.edu Abstract Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical F(ST) approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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From the study. Now If I mention your name in a post just salute me.
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There are [u]2 primary explanations for the evolution of lighter skin in regions of low UVR[/u]. The first suggests that light skin is merely due to the relaxation of functional constraint and that derived alleles associated with lighter pigmentation may have simply drifted to high frequency in the absence of strong purifying selection (Brace 1963). ****edit by xyyman-now Makova 2006**** The [u]second explanation [/u]suggests that in lowerUVRregions, positive selection would have favored mutations leading to lighter skin as a way to maximize cutaneous vitamin D synthesis (Rana et al. 1999; Jablonski and Chaplin 2000).
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by xyyman: @ KIk As Kittles stated in that paper there are TWO, yes TWO, conventional views on the HOW. Of course the paper I cited above says there are more than two. Nevertheless the leaders are Jablonski in one camp and Makova in the other. In that paper Kittles and his co-author is leaning towards Makova.
You mean as Norton and Kittles note in the paper. Either way, you're an idiot, as Jablosnki noted both of these as the explanation back in 2000...
The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis. --Jablonki, Chaplin
Again, if it's solely due to latitude and UV exposure, why did it take Europeans tens of millenia before turning pale? What's your scientific explanation for this?
quote:Originally posted by xyyman: Native Americans entered the Americas light skin NOT dark.
Nope, Native Americans enterted the Americas before lightskin became widespread as noted below...
Interestingly, derived allele frequencies at this locus are quite different between Native American (15%) and East Asian populations (45%), suggesting that perhaps the derived allele at this locus did not reach very high frequencies in East Asians until after the colonization of the Americas.--Norton, KittlesPosts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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quote:Originally posted by xyyman: You and others (like many racist)need to keep up. You keep going back to that archaic Penn study. We now know that SLC24A45 is just ONE of MANY genes that impact skin color. You guys seem to have a hard on for that study . . . . .and that gene. There are several genes that impact skin color. SLC24A45 is just one of many. Europeans have a higher frequency, yes, but Asians and Native Americans have ZERO. Asians and Native Americans have a higher frequency of ASIP. Khoi-San has OCA2. Note Europeans also has high frequency of ASIP and OCA2 and other “depigmentation” genes.
Now please don’t waste my time.
Are you acting like you're somehow teaching me that there's more than one gene identified? Lmao you're hilarious. I've known about the other derived alleles for years, you make no point.
See below, I've long discussed all alleles involved..
quote:Originally posted by MindoverMatter718: [QB] The ancestral state being at TYR A192C, MATP C374G, and SLC24A5 A111G which predominates in sub-Saharan Africa and Island Melanesia, the derived state of these alleles on the other hand which are TYR, 192*A, MATP 374*G and SLC24A5 111*A, predominate in Europe, which is consistent with the FST results of the the distributions of both ancestral and derived, indicating that the derived version is strongly a European specific divergent at these loci.
^^You're not teaching me anything new kid.
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posted
I give tutorials in case you are interested.. . .
yeah that's right play dumb.
You missed it? I am with Makova NOT Jablonski. I thought I made that clear.
quote:Originally posted by xyyman: Who is your daddy???
From the study. Now If I mention your name in a post just salute me.
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There are [u]2 primary explanations for the evolution of lighter skin in regions of low UVR[/u]. The first suggests that light skin is merely due to the relaxation of functional constraint and that derived alleles associated with lighter pigmentation may have simply drifted to high frequency in the absence of strong purifying selection (Brace 1963). ****edit by xyyman-now Makova 2006**** The [u]second explanation [/u]suggests that in lowerUVRregions, positive selection would have favored mutations leading to lighter skin as a way to maximize cutaneous vitamin D synthesis (Rana et al. 1999; Jablonski and Chaplin 2000).
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by xyyman: Who is your daddy???
From the study. Now If I mention your name in a post just salute me.
====
There are [u]2 primary explanations for the evolution of lighter skin in regions of low UVR[/u]. The first suggests that light skin is merely due to the relaxation of functional constraint and that derived alleles associated with lighter pigmentation may have simply drifted to high frequency in the absence of strong purifying selection (Brace 1963). ****edit by xyyman-now Makova 2006**** The [u]second explanation [/u]suggests that in lowerUVRregions, positive selection would have favored mutations leading to lighter skin as a way to maximize cutaneous vitamin D synthesis (Rana et al. 1999; Jablonski and Chaplin 2000).
Again, Jablosnki says it's both, her explanation is much more scientific than you simply saying "I don't know why it took then tens of millenia if it's merely due to relaxation of functional constraint "...as it's proven that lighterskin populations synthesize UV rays and turn it in vitamin D quicker than darkerskin, along with the fact that high intake of vitamin D rich foods keeps Eskimos darker than Europeans despite inhabiting a lower UV environment.
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.
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1. There is strong evidence of the harms of exposure to UV radiation from the sun and other sources, including skin cancer, melanoma and some cataracts. Based on expert consensus, sun protection is required when the UV index is 3 (moderate) or higher.
2. There is strong evidence of the benefits of adequate vitamin D status on musculoskeletal health and prevention of fractures in the elderly. There is also a growing body of evidence that vitamin D may have beneficial effects on some types of cancer, in particular colorectal cancer. Experts are concerned that vitamin D status may be too low in the general population to achieve these health benefits.
3. Vitamin D is obtained through skin exposure to UVB radiation, and also through diet (particularly fortified foods) and supplementation. To minimize the health risks associated with UVB radiation exposure while maximizing the potential benefits of optimum Vitamin D status, supplementation and small amounts of sun exposure are the preferred methods of obtaining vitamin D.
The known risks associated with unprotected UVB exposure must be weighed against its benefits as a source of vitamin D. For example, it is possible that just a few minutes a day of unprotected sun exposure will increase vitamin D status, but for some, may also increase the risk of skin damage. Factors such as age, diet, skin pigmentation, geographic location and intensity of the sun will affect the amount of sun exposure needed to produce adequate vitamin D. More research is needed in this area before any more specific recommendations can be made.
4. Groups at risk of not obtaining adequate amounts of vitamin D include:
· the elderly;
· exclusively breast-fed babies;
· individuals with dark skin pigmentation;
· individuals with limited skin exposure to the sun (e.g. housebound, or those who wear clothing covering most of the skin for cultural/religious reasons); and
· those who during the winter are living above 37 degrees latitude (Canada and Northern US).Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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Quote: “fact that high intake of vitamin D rich foods keeps Eskimos darker than Europeans despite inhabiting a lower UV environment.”
The “dark Asian” populations are NEW to the area. I thought I made that clear. Do you want me to post the study? Com’on man! READ!!!! Give up and on that food nonsense already!!!
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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posted
If they're new to the area, how come they exhibit the most cold adapted body plans of all humans? I'm still waiting on you to answer this...how come they suffer from vitamin D deficiency if their diets change from traditional fish, whale blubber etc..which is high in vitamin d?
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quote:Originally posted by xyyman: I am with Makova NOT Jablonski. I thought I made that clear.
Jablonski says the same thing jackass...so you do agree with her,
The clinal gradation of skin coloration observed among indigenous peoples is correlated with UV radiation levels and represents a compromise solution to the conflicting physiological requirements of photoprotection and vitamin D synthesis. --Jablonki, Chaplin
^^you just don't agree with the Vitamin D synthesis.
But what other explanation would there be for Europeans to spend tens of millenia in Europe before turning white? Of course you have no answer for this but Jablonski does.
And as shown to you we can get an example of this from the Eskimos who retain their pigment despite inhabiting a lower UV environment than Europe, which due to high levels of vitamin D intake.
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posted
Two good questions. Let me correct that. One dumb and one good question. You answered your own dumb question “how come they suffer from vitamin D deficiency if their diets change from traditional fish, whale blubber etc..which is high in vitamin d?” Answer: “suffer from vitamin D deficiency. . . diets change. . which is high in vitamin d?” Duh. And of course their dark skin. Still don’t get, huh? Yes, dark skin is NOT advantageous in the North. . .or far South but Vit D deficiency did NOT trigger the mutation to light skin per Makova now Norton/Kittles. The food/diet had nothing to do with it.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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posted
So again, what keeps Eskimos pigmented despite inhabiting lower UV environments than Europe?
Why is their darkskin not advantageous? Is it because it prohibits the absorption of vitamin D through UV exposure? Of course it is lol.
If vitamin D deficiency didn't trigger the mutation to become pale in Europe, then why did it take tens of millenia for humans to turn pale in Europe?
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posted
I believe it was the Halliday/Trenton study on the Aleuts etc that put the Eskimos about 2000yrs in the region. Not enough time to depigment.
Get it!!!!!!
Man if I had a penny for every time I saved your asssh. . .
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by xyyman: Finally. . . . now you are catching on. . . .
quote:Originally posted by AGÜEYBANÁ(Mind718):
quote:Originally posted by xyyman: I am with Makova NOT Jablonski. I thought I made that clear.
^^you just don't agree with the Vitamin D synthesis.
Yea and you have no way of refuting it though, you just simply whine about how you disagree with it.
In turn what other explanation would there be for humans in Europe to spend tens of millenia in Europe before turning pale?
We know early Europeans were hunter gatherers hence their whole diet consisted of high vitamin D rich foods, and when agriculture came around the switch involved a lower vitamin D intake from fish and animal meat to grains etc...
We know Eskimos are more pigmented than Europeans despite inhabiting lower UV environments, and we know the traditional Eskimo diet involved immensely high amounts of vitamin D rich foods.
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posted
KIK I will make it simple for you. Read the Makova study. There are many more that disagree with Jablonski/Chaplin and this vit D/diet change nonsense.
In a nutshell Makova and others are saying that light skin is the “natural state” IF there is NO physical pressure. In other words ALL population will lighten when the stimulus is removed ie high UV. See the study on San and Bantus in South Africa. There is also another study on South East Asians which confirmed this. So please stop parroting this Jablonski nonsense. We have moved on from that… “old” Penn Study.
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by xyyman: I believe it was the Halliday/Trenton study on the Aleuts etc that put the Eskimos about 2000yrs in the region. Not enough time to depigment.
Get it!!!!!!
Man if I had a penny for every time I saved your asssh. . .
Nope, arctic small tool tradition dates back further than that about 5kya, and there are artifacts found in Siberia going back to perhaps 18,000 years ago.
You can post the Holliday study though...
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quote:Originally posted by xyyman: KIK I will make it simple for you. Read the Makova study. There are many more that disagree with Jablonski/Chaplin and this vit D/diet change nonsense. In a nutshell Makova and others are saying that light skin is the “natural state” IF there is NO physical pressure. In other words ALL population will lighten when the stimulus is removed ie high UV. See the study on San and Bantus in South Africa. There is also another study on South East Asians which confirmed this. So please stop parroting this Jablonski nonsense. We have moved on from that… “old” Penn Study.
Well then you should have no trouble explaining how come it took tens of millenia for Europeans to turn pale right?
Obviously you know your dumbass is wrong, which is why you keep on ducking and dodging directly answering this question.
Its not solely due to relaxation otherwise it wouldn't have taken Europeans tens of millenia to turn pale. Plain and simple, get it???
Also Eskimos would be just as pale as Europeans are, but they're not... if you can't see that there's something else at play here you're an idiot.
If they disagree with Jablonski then quote their explanation for why Europeans spent tens of millenia in Europe before turning pale?
What's taking you so long?
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quote:Originally posted by AGÜEYBANÁ(Mind718): [QB] [QUOTE]Originally posted by xyyman: [qb] Finally. . . . now you are catching on. . . .
[QUOTE]Originally posted by AGÜEYBANÁ(Mind718):
We know early Europeans were hunter gatherers hence their whole diet consisted of high vitamin D rich foods, and when agriculture came around the switch involved a lower vitamin D intake from fish and animal meat to grains etc...
Virtually the only vitamin D rich diet is fish based. Hunter gatherer populations that were inland and not near rivers would not be included. Their depigmenation could have been thosuands of years faster than coastal or river based populations if the vitamin D hypothesis is correct
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posted
^^The information is out there and been posted before you just have to look...
Feb, 2001 - Three years ago, Jablonski and Chaplin took the spectrometer's global ultraviolet measurements and compared them with published data on skin color in indigenous populations from more than 50 countries. To their delight, there was an unmistakable correlation: The weaker the ultraviolet light, the fairer the skin. Jablonski went on to show that people living above 50 degrees latitude have the highest risk of vitamin D deficiency. "This was one of the last barriers in the history of human settlement," Jablonski says. "Only after humans learned fishing, and therefore had access to food rich in vitamin D, could they settle these regions."
quote:
The Biology of Skin Color: Black and White
The evolution of race was as simple as the politics of race is complex By Gina Kirchweger
Ten years ago, while at the university of Western Australia, anthropologist Nina Jablonski was asked to give a lecture on human skin. As an expert in primate evolution, she decided to discuss the evolution of skin color, but when she went through the literature on the subject she was dismayed. Some theories advanced before the 1970s tended to be racist, and others were less than convincing. White skin, for example, was reported to be more resistant to cold weather, although groups like the Inuit are both dark and particularly resistant to cold. After the 1970s, when researchers were presumably more aware of the controversy such studies could kick up, there was very little work at all. "It's one of these things everybody notices," Jablonski says, "but nobody wants to talk about."
No longer. Jablonski and her husband, George Chaplin, a geographic information systems specialist, have formulated the first comprehensive theory of skin color. Their findings, published in a recent issue of the Journal of Human Evolution, show a strong, somewhat predictable correlation between skin color and the strength of sunlight across the globe. But they also show a deeper, more surprising process at work: Skin color, they say, is largely a matter of vitamins.
Jablonski, now chairman of the anthropology department at the California Academy of Sciences, begins by assuming that our earliest ancestors had fair skin just like chimpanzees, our closest biological relatives. Between 4.5 million and 2 million years ago, early humans moved from the rain forest and onto the East African savanna. Once on the savanna, they not only had to cope with more exposure to the sun, but they also had to work harder to gather food. Mammalian brains are particularly vulnerable to overheating: A change of only five or six degrees can cause a heatstroke. So our ancestors had to develop a better cooling system.
The answer was sweat, which dissipates heat through evaporation. Early humans probably had few sweat glands, like chimpanzees, and those were mainly located on the palms of their hands and the bottoms of their feet. Occasionally, however, individuals were born with more glands than usual. The more they could sweat, the longer they could forage before the heat forced them back into the shade. The more they could forage, the better their chances of having healthy offspring and of passing on their sweat glands to future generations.
A million years of natural selection later, each human has about 2 million sweat glands spread across his or her body. Human skin, being less hairy than chimpanzee skin, "dries much quicker," says Adrienne Zihlman, an anthropologist at the University of California at Santa Cruz. "Just think how after a bath it takes much longer for wet hair to dry."
Hairless skin, however, is particularly vulnerable to damage from sunlight. Scientists long assumed that humans evolved melanin, the main determinant of skin color, to absorb or disperse ultraviolet light. But what is it about ultraviolet light that melanin protects against? Some researchers pointed to the threat of skin cancer. But cancer usually develops late in life, after a person has already reproduced. Others suggested that sunburned nipples would have hampered breast-feeding. But a slight tan is enough to protect mothers against that problem.
During her preparation for the lecture in Australia, Jablonski found a 1978 study that examined the effects of ultraviolet light on folate, a member of the vitamin B complex. An hour of intense sunlight, the study showed, is enough to cut folate levels in half if your skin is light. Jablonski made the next, crucial connection only a few weeks later. At a seminar on embryonic development, she heard that low folate levels are correlated with neural-tube defects such as spina bifida and anencephaly, in which infants are born without a full brain or spinal cord.
Jablonski and Chaplin predicted the skin colors of indigenous people across the globe based on how much ultraviolet light different areas receive. Graphic by Matt Zang, adapted from the data of N. Jablonski and G. Chaplin
Jablonski later came across three documented cases in which children's neural-tube defects were linked to their mothers' visits to tanning studios during early pregnancy. Moreover, she found that folate is crucial to sperm development -- so much so that a folate inhibitor was developed as a male contraceptive. ("It never got anywhere," Jablonski says. "It was so effective that it knocked out all folate in the body.") She now had some intriguing evidence that folate might be the driving force behind the evolution of darker skin. But why do some people have light skin?
As far back as the 1960s, the biochemist W. Farnsworth Loomis had suggested that skin color is determined by the body's need for vitamin D. The vitamin helps the body absorb calcium and deposit it in bones, an essential function, particularly in fast-growing embryos. (The need for vitamin D during pregnancy may explain why women around the globe tend to have lighter skin than men.) Unlike folate, vitamin D depends on ultraviolet light for its production in the body. Loomis believed that people who live in the north, where daylight is weakest, evolved fair skin to help absorb more ultraviolet light and that people in the tropics evolved dark skin to block the light, keeping the body from overdosing on vitamin D, which can be toxic at high concentrations.
By the time Jablonski did her research, Loomis's hypothesis had been partially disproved. "You can never overdose on natural amounts of vitamin D," Jablonski says. "There are only rare cases where people take too many cod-liver supplements." But Loomis's insight about fair skin held up, and it made a perfect complement for Jablonski's insight about folate and dark skin. The next step was to find some hard data correlating skin color to light levels.
Until the 1980s, researchers could only estimate how much ultraviolet radiation reaches Earth's surface. But in 1978, NASA launched the Total Ozone Mapping Spectrometer. Three years ago, Jablonski and Chaplin took the spectrometer's global ultraviolet measurements and compared them with published data on skin color in indigenous populations from more than 50 countries. To their delight, there was an unmistakable correlation: The weaker the ultraviolet light, the fairer the skin. Jablonski went on to show that people living above 50 degrees latitude have the highest risk of vitamin D deficiency. "This was one of the last barriers in the history of human settlement," Jablonski says. "Only after humans learned fishing, and therefore had access to food rich in vitamin D, could they settle these regions."
Humans have spent most of their history moving around. To do that, they've had to adapt their tools, clothes, housing, and eating habits to each new climate and landscape. But Jablonski's work indicates that our adaptations go much further. People in the tropics have developed dark skin to block out the sun and protect their body's folate reserves. People far from the equator have developed fair skin to drink in the sun and produce adequate amounts of vitamin D during the long winter months.
Jablonski hopes that her research will alert people to the importance of vitamin D and folate in their diet. It's already known, for example, that dark-skinned people who move to cloudy climes can develop conditions such as rickets from vitamin D deficiencies. More important, Jablonski hopes her work will begin to change the way people think about skin color. "We can take a topic that has caused so much disagreement, so much suffering, and so much misunderstanding," she says, "and completely disarm it."
posted
In other words. . . these groups, Eskimos etc, will lighten, in time, even if they ate fish for breakfast, lunch and dinner. LOL! according to opposing views to Jablonski/Chaplin.
Not sure WHEN Europeans depigmented but populations to take about 3-5000yrs to depigment. See the Central Americans and South African Bantus timeline. Remember northern Europe (low UV – with the palest people) did not have people till about 5000bc.
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quote:Originally posted by xyyman: Keep in mind central Americans are dark while those to the north and south are light. And if you don’t know what I am talking about then get out o
many of the North American Indians are dark
Teton Sioux Indians
Canadian
Mrs. Maria Ayuluk of Chevak, Alaska
Inuit
Inuit
Eskimo
When I look at various Northern Indians there seem to be a lot of inconsistencies of skin pigmenation
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Its because without the East Africans your ''blacks are phenotypically diverse'' argument crumbles.
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