posted
Of course as noted, the point in question was whether or not the San carried the derived allele as noted in the study "Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians" .
The following gives the definitive answer as to whether the San do in fact carry this allele or not, and if the authors were mistaking when noting it to be present.
There certainly are a few pointers I will have to address in the response from Dr. Norton, but for now, I believe she answered our question and that answer is YES the San do indeed carry the derived allele at high frequencies.
One note that I will certainly address is simply that I would see it from a point of view (as she notes some to see it) that dark skin evolved so long ago in our non anatomically modern human ancestors that the ancestral state of light pigmentation under the fur (if were to be entertained), of our non AMH ancestors if indeed was light, has nothing to do with AMH, since when AMH arose the ancestral state of dark pigmentation in our primate non AMH ancestors was already present into our physiognomy 1.2 million years ago, therefore AMH arose in a darkskin ancestral AMH state.
Also similar to the cognitive thinking which recently has been noted to be already set in homo erectus well before AMH arose, which blows the concept of cognitive thinking being an evolved trait that magically occurred 40kya when AMH entered Europe.
quote: Dear (name withheld)
Thank you for your interest in my work. I'm not sure that I fully understand your question--are you asking me if it is correct to interpret light pigmentation of the San as a derived trait, or that the A allele in the OCA2 gene (rs1800404) is derived? Let me try to address both. First, the "A" allele observed at such high frequency among the San is derived. When we talk about alleles being ancestral or derived we are basing this terminology on what allele is carried by other primates (usually chimpanzee). At this particular SNP, chimps, orangutans, and macaques all carry the G allele (to my knowledge, the A allele has not yet been observed in these species). So, for rs1800404, the G allele is considered ancestral while the alternative, the "A" is derived. Of course, this does not mean that the light pigmentation of the San is entirely due to derived alleles (for example, at the other SNPs in that study the San overwhelmingly carry the ancestral allele). Pigmentation is a complex trait that is determined by multiple genetic loci. Although we know that rs1800404 has an effect on skin pigmentation, I would be very surprised if it is responsible for all of the variation between the lightly pigmented San and more darkly pigmented neighboring African populations. It may be that in addition to carrying the derived allele at rs1800404 the San also carry ancestral alleles (those found in non-human primates) that are associated with light skin. I say "ancestral" here because many, like Jablonski and Chaplin or Rogers and Iltis would argue that humans evolved from a creature that had lightly pigmented skin under a coat of dark hair or fur. The question of whether light pigmentation in humans is derived is a bit more tricky. As I just mentioned, many assume that the ancestor of modern humans had light pigmentation under a dark coat of fur or hair, and that as you note dark pigmentation evolved when that fur was lost in response to the high UVR pressures of an African environment. In that sense, some would consider light pigmentation to be ancestral and darker pigmentation to be a derived state (with the lighter pigmentation observed in European and East Asian populations re-evolving much later in human history, most likely due to new, unique mutations such as the ones in SLC24A5 and MATP). Other people are of the opinion that dark pigmentation evolved so long ago in human history that it's acceptable to consider dark pigmentation the ancestral state. Personally I really don't think it matters as long as one is clear about which you consider to be ancestral and why. As for the environment of southern Africa influencing the pigmentation of the San, I could not say. I assume that by environment you are referring to the UVR intensity there, which is surely not as intense as it would be further north and closer to the equator. It is certainly a plausible idea, but much depends on how long the San have resided in that region and how strong selection for lighter pigmentation would have been (very strong selection could lead to a rapid change in pigmentation). If I have misunderstood your question please let me know and I'll do my best to (re)answer it. best,
~Heather Norton
Heather L. Norton Ph.D. ARL-Biotechnology 1041 East Lowell Street Bioscience West, Room 246 University of Arizona Tucson, AZ 85721
My initial e-mail for those interested...
quote: On Jan 11, 2010, at 2:36 PM, (name withheld) wrote:
Greetings, Dr, Norton.
I was recently engaged in a debate with my peers regarding your study re; "Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians". We began discussing the alleles associated with darker pigmentation vs. lighter pigmentation. As you allude to in the study there are derived alleles associated with lighterskin, and an ancestral allele associated with darker skin, the ancestral allele of which dominates in Sub-Saharan Africa and Island Melanesia. Of course this dark pigmentation arose as a consequence due to loss of fur and the need to protect the skin against harmful UV rays, while also helping to preserve the folate reserves in order to produce successful offsprings in a tropical environment. The exception came when the south African San hunter gatherers were brought into play. Your study notes that the derived allele is heavily present in the San (93%), this is interesting as it specifically notes that the San of southern Africa's lighter complexion is indeed a derived state, and not the ancestral. Would I be correct in making this assessment? Also, perhaps the subtropical environment of southern Africa (which mimics temperature somewhat similar to the Mediterranean) had something to do with this lighterskin pigmentation of the San hunter gatherers? Can you please elaborate on this further, it would be most highly appreciated. Thanks in advance. Here's two snippets from the study so you can get an idea quickly of what I mean....
Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians Heather L. Norton,*1 Rick A. Kittles
quote: In contrast, the **ancestral allele** associated with **dark pigmentation** has a shared high frequency in **sub- Saharan African and Island Melanesians**.A notable exception is the relatively lightly pigmented San population of Southern Africa where the **derived allele** predominates (93%), although this may be simply due to small sample size (n514). The distributions of the **derived and ancestral alleles** at TYR A192C, MATP C374G, and SLC24A5 A111G are consistent with the FST results suggesting strong Europeans pecific divergence at these loci. The *derived allele* at TYR, 192*A (previously linked with lighter pigmentation [Shriver et al. 2003]), has a frequency of 38% among European populations but a frequency of only 14% among non-Europeans. The differences between Europeans and non-Europeans for the MATP 374*G and SLC24A5 111*A alleles (both derived alleles associated with lighter pigmentation) were even more striking (MATP European 5 87%; MATP non-European 5 17%; SLC24A5 European 5 100%; SLC24A5 non-European 5 46%). The frequency of the SLC24A5 111*A allele outside of Europe is largely accounted for by high frequencies in geographically proximate populations in northern Africa, the Middle East, and Pakistan (ranging from 62% to 100%).
and if you will note...
"The lightly pigmented hunter-gatherer San populations of Southern Africa is exceptional in having a high frequency of the derived allele relative to geographically proximate and more darkly pigmented African populations (Jablonski and Chaplin 2000), further supporting the importance of OCA2 in regulating normal variation in pigmentation. The widespread distribution of the derived allele in the CEPH-Diversity Panel suggests that it is not necessarily a new mutation, nor has it been restricted to a specific geographic area. - Norton, Kittles et al."
Sincerely yours,
(name withheld).
Chimu you can now disappear for a year again...
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Thanks MindoverMatter for sharing this. It seems to confirm what I said in reply to your last post, don't you think?
-------------------- The Complete Picture of the Past tells Us what Not to Repeat Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:----- Original Message ----- From: Heather Norton Sent: Thursday, January 14, 2010 7:20 PM Subject: Re: Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians
Dear Jaime, In the 2006 paper we said that in the San the light allele at a particular SNP in the OCA2 gene (rs1800404) was most often found in the derived state--that is, most individuals carried one or two "A" alleles as opposed to the "G" allele which predominated in the other African populations surveyed. We determine whether a SNP is ancestral or derived based on which allele is found in other primate species--usually chimpanzee. In this case chimpanzees, orangutans, and macaques all carry the G allele at this site--the A allele has not been observed (to my knowledge) in these species. However, remember that pigmentation is controlled by multiple loci, and although we know that OCA2 plays an important role in skin pigmentation, I would be very surprised to learn that the derived allele at this particular SNP can explain all of the variation in pigmentation between the San and other, more darkly pigmented African populations. So, while the San carry a derived allele at rs1800404, it's possible that at other SNPs they carry an allele common in other primates with light skin underneath their fur. At those loci (should they ever be identified), the San would be considered to carry the ancestral allele, while other, more darkly pigmented populations would carry the derived allele (which would presumably cause a greater amount of eumelanin to be produced). It's [u]entirely possible[/u] that the San's pigmentation can be explained by a mix of derived alelles (like the one at rs1800404) and ancestral alleles shared with other primates but not with their neighboring populations.
Remember, we are talking about one mutation in OCA2--there are many, many other mutations in this gene that could (and do) affect pigmentation (most notably eye pigmentation). So, I would say that this particular mutation (rs1800404) plays *some* role in the lighter pigmentation of the San, but that there are probably other mutations (either in OCA2 or in other genes) that contribute to the phenotype as well. I actually don't know if the # of differences between chimp and San at OCA2 is greater than the # of differences between chimp and other African populations--it would be interesting to find out (it would also be interesting to find this out for other pigmentation genes as well). The mutations that we believe are responsible for lighter pigmentation in European and East Asian populations are derived both relative to chimpanzees as well as to what is observed in most African populations (sometimes, when the chimpanzee sequence is not available we assume that the allele most common in African populations is the ancestral allele). Also, we know that at least some of those mutations (like rs1426654 in SLC24A5) alter the protein that is produced--another sign that they play an important role in influencing phenotype.
Best, ~Heather
So the San carry one mutation in the OCA2 that is not in chimpanzees that other Africans have (And chimpanzees are light skinned). But Dr. Tishkoff doesn't know, overall which populations have the most mutations on the OCA2 gene, and which ones are closer to the ancestral one shared with chimpanzees. The derived genes specified in the OOA populations are known because they are different to African populations.
Again, she is basically saying she doesn't know which skin tone is the derived state because other parts in the OCA2 play a role, and other genes play a role. So still inconclusive.
And any claims of derivation of the San (in ONE mutation on the OCA2, does not fully explain the lighter skin of the San, nor the lighter skin of the Bisa Sandawe in equatorial Tanzania.
posted
Could it be that "creole" soldier-boy that looks like a white militia wacko has you all chasing an irrelevant straw here? He has already modified his 2008 youtube "KhoiSan aren't black" position and the evidence, even if Norton is cautious at this time, is not going in his favor regarding derived gene. Just a thought.
Posts: 4254 | From: dasein | Registered: Jun 2009
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quote:Originally posted by anguishofbeing: Could it be that "creole" soldier-boy that looks like a white militia wacko has you all chasing an irrelevant straw here? He has already modified his 2008 youtube "KhoiSan aren't black" position and the evidence, even if Norton is cautious at this time, is not going in his favor regarding derived gene. Just a thought.
Actually, I have never changed my position. You guys brought up the derived gene claim to claim that San and Sandawe with their light skin were derived looks. I just addressed their claims. At first, it seemed Dr. Norton was saying they didn't know if the allele was derived or not, but now she has clarified and stated she is speaking about the entire OCA2. She doesn't know if, overall, that gene is closer to San or darker skinned populations. Of course, this is a sideline issue now, as my original premise still stands, and, as Dr. Norton has clarified, even if the entire OCA2 gene was derived in the San, it would not fully explain their lightness. And this derivative which can't even fully explain the San, isn't even attributed to the Bisa Sandawe.
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Private Pyle, you did argue back then on youtube that they are not black because they are light skinned. You came on ES with this same line and rasol et al. reacted by arguing the tone was derived, hence this "debate", resurrected by your email to Norton because you clearly didn't like her published conclusions. Now STFU.
Posts: 4254 | From: dasein | Registered: Jun 2009
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quote:Originally posted by anguishofbeing: Private Pyle, you did argue back then on youtube that they are not black because they are light skinned. You came on ES with this same line and rasol et al. reacted by arguing the tone was derived, hence this "debate", resurrected by your email to Norton because you clearly didn't like her published conclusions. Now STFU.
FU Beetlejuice, I clearly stated that they were not Black because they were light skinned and not identified as Black. And I was correct. But trends change. And now some San have been identifying as Black. Much like many light skinned people of mixed ancestry identify as Black in the US. As self identity is what I respect, then THOSE San are Black. And I verified the derived gene AS AN EXPLANATION FOR SAN BEING LIGHTER THAN BANTU. The explanation didn't hold. That is called verifying the claim with the source. Sorry you didn't like the outcome. Now go FYS
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quote:I clearly stated that they were not Black because they were light skinned
If you now admit that black is a subjective sociopolitical term and not a literal description how the f!ck are you going to argue the above? Unless you are some deranged agent provocateur?
quote:I clearly stated that they were not Black because they ... not identified as Black
How on earth could you be arguing that "they" are not black because "they" are "not identified as" such when there are San that do in fact identify as such?
quote:But trends change. And now some San have been identifying as Black.
WTF?! Some have identified as such well before 2008 pyle, that's my point, you failed to take this tiny part into account on your youtube page when you were busy arguing "they were not Black because they were light skinned and not identified as Black." This means you were/are a fraud and an agent provocateur who clearly has a problem with black folks.
quote: Sorry you didn't like the outcome.
You can take up this straw with rasol et al. Whether derived or not their "light skin" isn't result of "admixture" in the conventional sense. Sorry, your favorite Africans the San aren't "Creoles". Posts: 4254 | From: dasein | Registered: Jun 2009
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quote:Originally posted by Chimu: Got similar response.
quote:----- Original Message ----- From: Heather Norton Sent: Thursday, January 14, 2010 7:20 PM Subject: Re: Genetic Evidence for the Convergent Evolution of Light Skin in Europeans and East Asians
Dear Jaime, In the 2006 paper we said that in the San the light allele at a particular SNP in the OCA2 gene (rs1800404) was most often found in the derived state--that is, most individuals carried one or two "A" alleles as opposed to the "G" allele which predominated in the other African populations surveyed. We determine whether a SNP is ancestral or derived based on which allele is found in other primate species--usually chimpanzee. In this case chimpanzees, orangutans, and macaques all carry the G allele at this site--the A allele has not been observed (to my knowledge) in these species. However, remember that pigmentation is controlled by multiple loci, and although we know that OCA2 plays an important role in skin pigmentation, I would be very surprised to learn that the derived allele at this particular SNP can explain all of the variation in pigmentation between the San and other, more darkly pigmented African populations. So, while the San carry a derived allele at rs1800404, it's possible that at other SNPs they carry an allele common in other primates with light skin underneath their fur. At those loci (should they ever be identified), the San would be considered to carry the ancestral allele, while other, more darkly pigmented populations would carry the derived allele (which would presumably cause a greater amount of eumelanin to be produced). It's [u]entirely possible[/u] that the San's pigmentation can be explained by a mix of derived alelles (like the one at rs1800404) and ancestral alleles shared with other primates but not with their neighboring populations.
Remember, we are talking about one mutation in OCA2--there are many, many other mutations in this gene that could (and do) affect pigmentation (most notably eye pigmentation). So, I would say that this particular mutation (rs1800404) plays *some* role in the lighter pigmentation of the San, but that there are probably other mutations (either in OCA2 or in other genes) that contribute to the phenotype as well. I actually don't know if the # of differences between chimp and San at OCA2 is greater than the # of differences between chimp and other African populations--it would be interesting to find out (it would also be interesting to find this out for other pigmentation genes as well). The mutations that we believe are responsible for lighter pigmentation in European and East Asian populations are derived both relative to chimpanzees as well as to what is observed in most African populations (sometimes, when the chimpanzee sequence is not available we assume that the allele most common in African populations is the ancestral allele). Also, we know that at least some of those mutations (like rs1426654 in SLC24A5) alter the protein that is produced--another sign that they play an important role in influencing phenotype.
Best, ~Heather
So the San carry one mutation in the OCA2 that is not in chimpanzees that other Africans have (And chimpanzees are light skinned). But Dr. Tishkoff doesn't know, overall which populations have the most mutations on the OCA2 gene, and which ones are closer to the ancestral one shared with chimpanzees. The derived genes specified in the OOA populations are known because they are different to African populations.
Again, she is basically saying she doesn't know which skin tone is the derived state because other parts in the OCA2 play a role, and other genes play a role. So still inconclusive.
And any claims of derivation of the San (in ONE mutation on the OCA2, does not fully explain the lighter skin of the San, nor the lighter skin of the Bisa Sandawe in equatorial Tanzania.
Lol chimu, its not inconclusive as Norton specifically notes that the San do carry the derived allele A, and not ancestral G on the OCA2 allele. G which is shared by non human primates so its ancestral and dominate in other neighboring populations. This was the whole point whether or not the San carried this derived allele at high frequencies and as shown they really do. Sorry chimu but you're done with.
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quote:Originally posted by anguishofbeing: If you now admit that black is a subjective sociopolitical term and not a literal description how the f!ck are you going to argue the above? Unless you are some deranged agent provocateur?
Dream on. It is a subjective sociopolitical term. But it arose from the usage of hyperbolic terms to describe human populations based on skin color.
First you had Blacks (Bantu) and Coloureds (San and people of mixed ancestry). Then you had Blacks (Bantu and some San) and Coloureds (other San and people of mixed ancestry).
In fact, most San really want their own identity, not Coloured, not Black. Coloured delegitimized them as the original population of South Africa. And Black became the adopted term for Native in South Africa. These terms effectively erased the legitimacy of claims of San as the original inhabitants, first removing it from them by claiming the were just mixed foreigners (Bantu and European) and then later with the Black movement claiming African indigenuousness, again denied the San of the right to be called first peoples and present their grievances.
quote:You can take up this straw with rasol et al. Whether derived or not their "light skin" isn't result of "admixture" in the conventional sense. Sorry, your favorite Africans the San aren't "Creoles".
The only one presenting strawmans is yourself. Both Coloured (Mixed) and Black (Bantu) have been imposed identities on the San. Neither was freely embraced by them, but adopted by necessity. They are not mixed, and they are not dark skinned Bantu. But some have chosen to identify as Black, and that is their right. If it helps them in their struggles, good for them. Others still choose not to identify as Coloured or Black.
quote:Originally posted by MindoverMatter718: [Lol chimu, its not inconclusive as Norton specifically notes that the San do carry the derived allele A, and not G on the OCA2 allele. G which is shared by non human primates so its ancestral and dominate in other neighboring populations. This was the whole point whther or not the San carried this derived allele at high frequencies and as shown they really do. Sorry chimu but you're done with.
Wrong again. The whole point was if the San had a derived state of lighter skin color, not if they just carried a derivative mutation. Dr. Norton has clarified that there is a derivative mutation, not carried by primates, but has also clearly stated that this is not proof that lighter San are derived from darker skinned populations. Nice try.
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The San do indeed carry the derived allele at high frequencies and that's the point, the derived allele is associated with lighter pigmentation as noted already, of course you're simply grasping at straws since its known that this derived allele may not explain the whole situation of why the San are lighter but it sure does give us a better idea of why! The presence of these derived alleles at high frequencies lets anyone with a brain know that the Sans skin color is not in its ancestral state. Sorry but you lose!
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quote:Originally posted by The Explorer: Thanks MindoverMatter for sharing this. It seems to confirm what I said in reply to your last post, don't you think?
No problem, and yes it does seem to confirm what you said before.
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quote: Dream on. It is a subjective sociopolitical term. But it arose from the usage of hyperbolic terms to describe human populations based on skin color.First you had Blacks (Bantu) and Coloureds (San and people of mixed ancestry). Then you had Blacks (Bantu and some San) and Coloureds (other San and people of mixed ancestry).In fact, most San really want their own identity, not Coloured, not Black. Coloured delegitimized them as the original population of South Africa. And Black became the adopted term for Native in South Africa. These terms effectively erased the legitimacy of claims of San as the original inhabitants, first removing it from them by claiming the were just mixed foreigners (Bantu and European) and then later with the Black movement claiming African indigenuousness, again denied the San of the right to be called first peoples and present their grievances.
Straw. Nothing here takes away from the fact that, when all is said and done, "black" is a subjective term based on a combination of societal convention and also personal individual identity politics. Get over it you color obsession weirdo.
quote: The only one presenting strawmans is yourself. Both Coloured (Mixed) and Black (Bantu) have been imposed identities on the San. Neither was freely embraced by them, but adopted by necessity. They are not mixed, and they are not dark skinned Bantu
LOL you projecting imbecile; you really can't help yourself can you? All the above is nothing but useless straw again; has no bearing on the fact that before on youtube you deceitfully left out this important part "some have chosen to identify as Black" and therefore "Those that identify as Black are Black"; of course that would have exposed your presumptuous white ass arguing that they are in fact not Black because they are light skinned and not identify as Black. Dismissed private pyle!
But watch soldier boy come back with yet more straws like the frustrated color obsessed anti-Afrocentric lunatic he is. lol
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I wonder what straw Chimu will try to come back and fabricate with next, since this was the last straw he was grasping at, he no longer has legs to stand on. Lol @ him trying to say that the high frequencies of derived alleles present in the San doesn't have anything to do with their lighterskin complexion, of course it does the poor fool is just seriously in denial.
Like I said, of course the presence of these derived alleles at high frequencies lets anyone with a functioning brain know that the San's skin color is obviously not in its ancestral state, otherwise they wouldn't carry the derived A allele, but instead would carry the ancestral G allele common in chimps on the OCA2 gene.
R.I.P. to Chimu and his obsession with the San and Sandawe, as he somehow believed them to be representative of lighter skin in Africa as an ancestral state...
Truthfully I think Chimu will be so stubborn, since this was his claim to fame, that he still wouldn't admit the high frequency of derived alleles played a role in lightening up the San...watch!!
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So the San carry one mutation in the OCA2 that is not in chimpanzees that other Africans have (And chimpanzees are light skinned). But
There is not "but" here; you were denying that the published journal which says so point blank was making an informed judgment and non-accidental description about that one locus. You had been DEBUNKED without delay. Not even your "sympathy" e-mail correspondence would save the day.
quote:
Dr. Tishkoff doesn't know, overall which populations have the most mutations on the OCA2 gene
I think you meant to say Norton, rather than Tishkoff? In any case, are you implying there are other OCA2 derivatives that did not come to Norton et al.'s attention across the diverse geographical samples?
quote:and which ones are closer to the ancestral one shared with chimpanzees. The derived genes specified in the OOA populations are known because they are different to African populations.
You were just told that the San don't share the said OCA2 allele with furry primates. That right there; what does it tell you? Of course, the derived alleles are identified with comparison to predominating tropical African patterns. That is how it is done. Is there any other way to make a valid and informed comparison?
quote: Again, she is basically saying she doesn't know which skin tone is the derived state because other parts in the OCA2 play a role, and other genes play a role. So still inconclusive.
That is an outright lie. There is a general agreement, even according to your first correspondence, that dark skin would have been the default condition of anatomically modern humans, and lighter skin would have been the "derived" condition. Norton is by no means implying that "white" anatomically modern firsts is even a consideration. Yes, it doesn't take a genius to figure that a single locus could NOT be responsible for skin tone continuum amongst the San, but I guess, you just figured that out. Fact is, definitive DNA patterns have been seen between tropical Africans, Eurpeans and East Asians [who had the most divergent patterns in the bunch] and other groups. These patterns make it quite clear which are the likely upstream molecular alleles for modern humans and which one's likely were not.
Read and learn:
Pairwise Fst estimates for the ASIP A8818G and OCA2 A355G SNPs tentatively suggest a pattern of divergence between 4 populations (Europeans, East Asians, Native Americans, and South Asians) and the relatively more darkly pigmented populations of West Africa and Island Melanesia, or possibly only between West Africans and all other populations. At both loci, West Africans and Island Melanesians have higher frequencies of the ancestral alleles than the other 4 populations. Pairwise locus-specific Fst values falling in the top 5% of the empirical distributions are observed between West Africans and 3 other populations (South Asians, Native Americans, and Europeans) at ASIP A8818G. Fst values between West Africans and East Asians at this locus are elevated but do not reach our cutoff value of 5% (Fst = .489, P = .065). At OCA2 A355G, only West Africans and Europeans show Fst values falling into the top fifth percentile of relevant comparisons (Fst = .516, P<.05). The low pair wise Fst values and higher frequency of ancestral alleles at both SNPs studied in these loci between West Africans and Island Melanesians hint that dark pigmentation associated with both loci in these populations may have a common evolutionary origin (Mean Fst (WA-IM) = .182; ASIP A8818G Fst (WA-IM) = .260, P = .282; OCA2 A355G Fst (WA-IM) = .101, P=.525).
What does the above Fst distance patterns mean?
quote: And any claims of derivation of the San (in ONE mutation on the OCA2, does not fully explain the lighter skin of the San, nor the lighter skin of the Bisa Sandawe in equatorial Tanzania.
And here I was, thinking that this was your mentality, and hence, your insistence that it must be THE allele in the Sandawe, even though you offer no proof for such a supposition and even though the Sandawe is not the centre of anyone's talking point but your's. Yet as strange as it is, you are now implying others were thinking that way...like you were.
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The only one presenting strawmans is yourself. Both Coloured (Mixed) and Black (Bantu) have been imposed identities on the San. Neither was freely embraced by them, but adopted by necessity. They are not mixed, and they are not dark skinned Bantu. But some have chosen to identify as Black, and that is their right. If it helps them in their struggles, good for them. Others still choose not to identify as Coloured or Black.
The Bantu are not dark as the Dinka, yet that doesn't stop them from being considered "black", nor is the San. Your mentality is bankrupt. Your subjective political opinions don't hold any more water than those you reject. LOL
quote:
Wrong again. The whole point was if the San had a derived state of lighter skin color, not if they just carried a derivative mutation.
In your case, your whole point was to deny that the example found in high frequencies in the San sample [even though it could be a matter of sample size] was the derived counterpart, and backfired.
quote: Dr. Norton has clarified that there is a derivative mutation, not carried by primates, but has also clearly stated that this is not proof that lighter San are derived from darker skinned populations. Nice try.
You have to consider where much of San territory is, limb-trunk and limb proportions and other anatomy to make an informed assessment of whether some adaptation could have taken place since their residence in sub-tropical regions. Granted, the San are not that light to begin with...at least, it pales in comparison to some coastal northwest Africans, whose' in turn pale in comparison to northern Europeans. It is logical to assume that some modification indeed took place since their arrival to the sub-tropical environment of Africa; why could some lax in skin tone pigmentation not be one aspect of this? OCA2 may just be one locus, but its distribution pattern, along with other loci, are instructive. How do you explain the patterns observed between tropical Africans and other groups, if one is to assume the position that San did not undergo some modification in skin pigmentation?
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quote:and which ones are closer to the ancestral one shared with chimpanzees. The derived genes specified in the OOA populations are known because they are different to African populations.
You were just told that the San don't share the said OCA2 allele with furry primates. That right there; what does it tell you? Of course, the derived alleles are identified with comparison to predominating tropical African patterns. That is how it is done. Is there any other way to make a valid and informed comparison?
Lol Chimu is either slow at learning or blatantly being ignorant, because it's stated clearly, and hence he should know full and well that the San carry a high frequency of the derived "A" allele on the OCA2 gene, which is NOT shared with earlier primates, whereas the "G" allele on the OCA2 gene is shared between these early primates and other Africans which then indicates the "G" allele is ancestral.
I mean seriously, who does this guy think he's fooling? Lol
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posted
Even in the second response from Dr. Norton (yes, he e-mailed her again lol) she specifically let's the guy know what the siutation is, yet he's still having a hard time coming to terms with it....
quote:Originally posted by Chimu:
Dear Jaime, In the 2006 paper we said that in the San the light allele at a particular SNP in the OCA2 gene (rs1800404) was most often found in the derived state--that is, most individuals carried one or two "A" alleles as opposed to the "G" allele which predominated in the other African populations surveyed. We determine whether a SNP is ancestral or derived based on which allele is found in other primate species--usually chimpanzee. In this case chimpanzees, orangutans, and macaques all carry the G allele at this site--the A allele has not been observed (to my knowledge) in these species.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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Lol Chimu is either slow at learning or blatantly being ignorant, because it's stated clearly, and hence he should know full and well that the San carry a high frequency of the derived "A" allele on the OCA2 gene, which is NOT shared with earlier primates, whereas the "G" allele on the OCA2 gene is shared between these early primates and other Africans which then indicates the "G" allele is ancestral.
I mean seriously, who does this guy think he's fooling? Lol
I'm willing to bet that like the OCA2 allele, the San may show some variation with the predominating examples in tropical Africa at some other loci, but that they share a good deal of other ancestral variants with tropical African groups. The derived OCA2 allele is found amongst tropical African groups, but at fairly modest frequencies, compared to the ancestral allele. Hence, its function in those groups is nothing more than normal variation within the populations involved. However, the issue here with the San, though more than likely independent from the episodes involving Europeans and East Asians, is that the marker could have been selected for, and hence, maintained in fairly visible frequencies, if not high frequencies. The allele variant would not be selected for, until later on in Europeans and East Asians.
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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I agree that the San may likely show variation in other areas, definitely needs to be checked, and share a good deal with other tropical groups, I.e., San and Ethiopians sharing the deepest clade
But why the San show this high frequency of the derived allele on the OCA2 that we currently know of, needs to be further investigated.
Of course we know OCA plays a role in pigmentation and we see the San are relatively light in comparison to more tropical Africans, hence it's not rocket science to note this derived state on the OCA2 gene to be a quick no-brainer as to why the San might be lighter, but why, was it the sub-tropical environment that could account for some variation? This is what really needs to be further investigated. As your post here also alludes to...
quote:You have to consider where much of San territory is, limb-trunk and limb proportions and other anatomy to make an informed assessment of whether some adaptation could have taken place since their residence in sub-tropical regions
and Dr Norton notes to be a plausible idea..
quote:As for the environment of southern Africa influencing the pigmentation of the San, I could not say. I assume that by environment you are referring to the UVR intensity there, which is surely not as intense as it would be further north and closer to the equator. It is certainly a plausible idea, but much depends on how long the San have resided in that region and how strong selection for lighter pigmentation would have been (very strong selection could lead to a rapid change in pigmentation).---Norton
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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hence it's not rocket science to note this derived state on the OCA2 gene to be a quick no-brainer as to why the San might be lighter, but why, was it the sub-tropical environment that could account for some variation? This is what really needs to be further investigated.
I think it is simple really. The San had undergone some selection for lax in skin pigmentation, as much of their territory spans the areas with less intense UV radiation than those near the equatorial regions. That they carry deep root uniparental clades, which are implicated in other African groups in any case, has little bearing on this response to environment. Skin tones vary amongst even the San; some more darker than others. Still, nowhere near the coastal northwestern Africans or those lighter thereof.
A San bushman with Dr. Spencer Wells Photograph: National Geographic Society
Ps - In fact, I'm guessing of the loci investigated by Norton et al., OCA2 is the region that stood out markedly between the San sample and other sub-Saharan African samples, where frequency is concerned. Otherwise, the authors would have followed suit, as they noted about the OCA2 locus, about the other designated loci.
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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posted
Soldier-boy emailed Norton again because he is genuinely troubled by the primacy of dark skin, which translates in his eyes to black people. Hence his misguided fixation on the San.
Posts: 4254 | From: dasein | Registered: Jun 2009
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posted
Seems that Chimu has went back into hiding again... Or perhaps e-mailing Norton once again.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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hence it's not rocket science to note this derived state on the OCA2 gene to be a quick no-brainer as to why the San might be lighter, but why, was it the sub-tropical environment that could account for some variation? This is what really needs to be further investigated.
I think it is simple really. The San had undergone some selection for lax in skin pigmentation, as much of their territory spans the areas with less intense UV radiation than those near the equatorial regions.
A no-brainer indeed.
quote:Originally posted by Chimu:
Lol, what exactly was Chimu trying to pull off here?
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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posted
^Presumably that the man is not "black", because he is not literally black.
The same photo was posted earlier in black and white, and now in this form, which looks like doctored work.
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:Originally posted by The Explorer: ^Presumably that the man is not "black", because he is not literally black.
The same photo was posted earlier in black and white, and now in this form, which looks like doctored work.
Lol indeed, it looks as if he tried to color this man in by using photoshop to fit one of the colors on the scale he posted alongside it... Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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posted
As funny as it may sound to the sane world, to Jaime/Chimu, if that man's skin is not colored in the same way as his hair, then he cannot be considered "black".
-------------------- The Complete Picture of the Past tells Us what Not to Repeat Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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That's because in Latin America, his birth culture, there are so many ways not to be considered black.
Some like Chimu are all for it. Others like MOM718 don't buy it. Here's a listing supplied by DougM.
1. Acastanhada (cashewlike tint; caramel colored) 2. Agalegada 3. Alva (pure white) 4. Alva-escura (dark or off-white) 5. Alverenta (or aliviero, "shadow in the water") 6. Alvarinta (tinted or bleached white) 7. Alva-rosada (or jamote, roseate, white with pink highlights) 8. Alvinha (bleached; white-washed) 9. Amarela (yellow) 10. Amarelada (yellowish) 11. Amarela-quemada (burnt yellow or ochre) 12. Amarelosa (yellowed) 13. Amorenada (tannish) 14. Avermelhada (reddish, with blood vessels showing through the skin) 15. Azul (bluish) 16. Azul-marinho (deep bluish) 17. Baiano (ebony) 18. Bem-branca (very white) 19. Bem-clara (translucent) 20. Bem-morena (very dusky) 21. Branca (white) 22. Branca-avermelhada (peach white) 23. Branca-melada (honey toned) 24. Branca-morena (darkish white) 25. Branca-pálida (pallid) 26. Branca-queimada (sunburned white) 27. Branca-sardenta (white with brown spots) 28. Branca-suja (dirty white) 29. Branquiça (a white variation) 30. Branquinha (whitish) 31. Bronze (bronze) 32. Bronzeada (bronzed tan) 33. Bugrezinha-escura (Indian characteristics) 34. Burro-quanto-foge ("burro running away," implying racial mixture of unknown origin) 35. Cabocla (mixture of white, Negro and Indian) 36. Cabo-Verde (black; Cape Verdean) 37. Café (coffee) 38. Café-com-leite (coffee with milk) 39. Canela (cinnamon) 40. Canelada (tawny) 41. Castão (thistle colored) 42. Castanha (cashew) 43. Castanha-clara (clear, cashewlike) 44. Castanha-escura (dark, cashewlike) 45. Chocolate (chocolate brown) 46. Clara (light) 47. Clarinha (very light) 48. Cobre (copper hued) 49. Corado (ruddy) 50. Cor-de-café (tint of coffee) 51. Cor-de-canela (tint of cinnamon) 52. Cor-de-cuia (tea colored) 53. Cor-de-leite (milky) 54. Cor-de-oro (golden) 55. Cor-de-rosa (pink) 56. Cor-firma ("no doubt about it") 57. Crioula (little servant or slave; African) 58. Encerada (waxy) 59. Enxofrada (pallid yellow; jaundiced) 60. Esbranquecimento (mostly white) 61. Escura (dark) 62. Escurinha (semidark) 63. Fogoio (florid; flushed) 64. Galega (see agalegada above) 65. Galegada (see agalegada above) 66. Jambo (like a fruit the deep-red color of a blood orange) 67. Laranja (orange) 68. Lilás (lily) 69. Loira (blond hair and white skin) 70. Loira-clara (pale blond) 71. Loura (blond) 72. Lourinha (flaxen) 73. Malaia (from Malabar) 74. Marinheira (dark greyish) 75. Marrom (brown) 76. Meio-amerela (mid-yellow) 77. Meio-branca (mid-white) 78. Meio-morena (mid-tan) 79. Meio-preta (mid-Negro) 80. Melada (honey colored) 81. Mestiça (mixture of white and Indian) 82. Miscigenação (mixed --- literally "miscegenated") 83. Mista (mixed) 84. Morena (tan) 85. Morena-bem-chegada (very tan) 86. Morena-bronzeada (bronzed tan) 87. Morena-canelada (cinnamonlike brunette) 88. Morena-castanha (cashewlike tan) 89. Morena clara (light tan) 90. Morena-cor-de-canela (cinnamon-hued brunette) 91. Morena-jambo (dark red) 92. Morenada (mocha) 93. Morena-escura (dark tan) 94. Morena-fechada (very dark, almost mulatta) 95. Morenão (very dusky tan) 96. Morena-parda (brown-hued tan) 97. Morena-roxa (purplish-tan) 98. Morena-ruiva (reddish-tan) 99. Morena-trigueira (wheat colored) 100. Moreninha (toffeelike) 101. Mulatta (mixture of white and Negro) 102. Mulatinha (lighter-skinned white-Negro) 103. Negra (negro) 104. Negrota (Negro with a corpulent vody) 105. Pálida (pale) 106. Paraíba (like the color of marupa wood) 107. Parda (dark brown) 108. Parda-clara (lighter-skinned person of mixed race) 109. Polaca (Polish features; prostitute) 110. Pouco-clara (not very clear) 111. Pouco-morena (dusky) 112. Preta (black) 113. Pretinha (black of a lighter hue) 114. Puxa-para-branca (more like a white than a mulatta) 115. Quase-negra (almost Negro) 116. Queimada (burnt) 117. Queimada-de-praia (suntanned) 118. Queimada-de-sol (sunburned) 119. Regular (regular; nondescript) 120. Retinta ("layered" dark skin) 121. Rosa (roseate) 122. Rosada (high pink) 123. Rosa-queimada (burnished rose) 124. Roxa (purplish) 125. Ruiva (strawberry blond) 126. Russo (Russian; see also polaca) 127. Sapecada (burnished red) 128. Sarará (mulatta with reddish kinky hair, aquiline nose) 129. Saraúba (or saraiva: like a white meringue) 130. Tostada (toasted) 131. Trigueira (wheat colored) 132. Turva (opaque) 133. Verde (greenish) 134. Vermelha (reddish)
I don't think there are these many categories in Peru but the general idea is the same, avoid being African or Indian and be of some kind of European whether a puro or a mixture.
Posts: 8014 | From: the Tekrur in the Western Sahel | Registered: Feb 2006
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posted
^^It seems to be that the list you posted was taken from a study in where Brazilian's were asked to identify themselves according to their skin color which of course doesn't account for other places in "Latin America"...
As you can see the following seems to be Spanish classifications in Mexico....
1.) Mestizo: Spanish father and Indian mother 2.) Castizo: Spanish father and Mestizo mother 3.) Espomolo: Spanish mother and Castizo father 4.) Mulatto: Spanish and black African 5.) Moor: Spanish and Mulatto 6.) Albino: Spanish father and Moor mother 7.) Throwback: Spanish father and Albino mother 8.) Wolf: Throwback father and Indian mother 9.) Zambiago: Wolf father and Indian mother 10.) Cambujo: Zambiago father and Indian mother 11.) Alvarazado: Cambujo father and Mulatto mother 12.) Borquino: Alvarazado father and Mulatto mother 13.) Coyote: Borquino father and Mulatto mother 14.) Chamizo: Coyote father and Mulatto mother 15.) Coyote-Mestizo: Cahmizo father and Mestizo mother 16.) Ahi Tan Estas: Coyote-Mestizo father and Mulatto mother
quote:Originally posted by alTakruri: Others like MOM718 don't buy it.
Not even for a penny...
P.s. I note your point though, and indeed this is the sort of mindset (anything but black), its like the reverse one drop rule of the U.S.A., i.e., you have one drop of white blood and that makes you white.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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posted
Yes, each country has its own. I once posted the ones in Peru but that thread was apparently deleted.
Many LA countries were as narrow defing white as they were black. White was reserved for those born in Iberia. A child of two Iberian puro parents if born in the western hemisphere were creole not white! Amazing.
UBBFriend: Email this page to someone!
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Or perhaps e-mailing Norton once again.
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