-------------------- 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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Explorer, But there are many instances of E in Europe--going only with Y haplotypes--so the fact that some trace elements of A are found in West Africa does not dislodge my hypothesis. Consider too the cases of R in Central/West Africa[Cameroon].
But back to my point: if the OOA is correct[the data says it is] then how do you explain the phenotypical transformation of non-Africans such as Europeans and Asians from having original African phenotypes to their present appearances? There must have been intermediary stages--that took place not only outside Africa but also inside Africa. In this regard no need for any fanciful ideas such as back migration.
Just document, using your imagination, the transforamtive steps taken.
Posts: 5492 | Registered: Nov 2004
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Lamin, let's first remember that I only commented on haplogroup A, because *you* brought it up, upon being queried to clarify your claim. I did so, with the understanding that you generalized west Africans, and used haplogroup A to argue for isolation and thus, greater distance between them and the San than vs. some non-Africans...in addition to the "size" justification centered on the Twa.
Your "distance" claim, pending clarification, seemed to imply the treating of west Africans as figures of autochthonous ancestry vs. "some non-Africans", the San and Twa as others of respective autochthonous ancestry. In that respect, it had the potential to mislead.
Now, you use E as a basis for your claim about the distance issue:
Firstly, the San are not devoid of Hg E, as you might be inclined to assume.
Secondly, E in Europe marks African ancestry; so of course, in that respect, such non-Africans will be closer to haplogroup E-carrying west Africans than Africans who fall out of that macro-haplogroup, from the Y DNA standpoint.
The fact that you mention Hg R in west Africa to reinforce your claim, which no doubt speaks to the heterogeneity of west Africans, is case in point about the futility of generalization as you did, wittingly or otherwise.
Evolution of phenotype of Europeans or other Asian groups has no bearing on African diversity vs. the non-African; phenotypic variation, including that within-population, remains greatest in Africa.
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:Posted by Lamin: But back to my point: if the OOA is correct[the data says it is] then how do you explain the phenotypical transformation of non-Africans such as Europeans and Asians from having original African phenotypes to their present appearances? There must have been intermediary stages--that took place not only outside Africa but also inside Africa. In this regard no need for any fanciful ideas such as back migration.
Allow me to explain this is "laymen" terms. You're clearly speaking upon the pale phenotype of East Asians and Europeans (since you should already know cranio-facially/phenotypically speaking, Africa pretty much covers the world, I won't go into details on that) . This evolution/mutation is a recent adaptation, considering an evolutionary time line. This occurred due to the fact when humans move into northern latitudes need to be lighter skinned in order to allow UV in to produce Vitamin D(since dark skin was evolved to protect from harmful UV, therefore it prevents from absorbing UV to produce Vitamin D).
Early humans as well as early Europeans were hunter gatherers, in a hunter gatherers diet you will find food which contains adequate amounts of Vitamin D, through fish, meats, egg yolks etc... Absorbing enough of this Vitamin D will provide humans with enough Vitamin D to keep their skin dark with no need to be pale, since their receiving the Vitamin D through their diets. A clear example of a human population which consumes adequate amounts of vitamin d and retains melanin, are Eskimos. If you do some research you will notice that an Eskimos diet consists of rich amounts of Vitamin D, and if they would stop eating this diet, Eskimos would develop Vitamin D deficiencies, which surface as rickets, the reason for this is as explained, when humans move to northern latitudes/lower uv environments they aren't receiving as much sun(obviously) and since dark skin protects from harmful UV rays, it blocks out the ability to produce synthesize UV. The sun is one main source of Vitamin D along with diet. So in northern latitudes under a farmers diet(which doesn't provide an individual with adequate amounts of Vitamin D as a hunter gatherers diet would) humans would have to be lighter skinned, as explained, to allow the synthesis of UV for the production of Vitamin D, since dark skin blocks out the sun
Therefore, as explained light skin was evolved to allow the synthesis of Uv for the production of Vitamin d, but remember early Europeans were hunter gatherers, just as Eskimos are/were, so early Europeans retained their melanin levels as well, until agriculture spread. But agriculture /farming didn't spread into Europe until about 8kya with the Neolitic revolution. This new way of living decreased Europeans intake of vitamin D, since a farmers diet is not full with the adequate amounts of Vitamin D that a hunter gatherers fisher/herders diet consists of.
Therefore during this era, Europeans and East Asians evolved pale skin to allow UV in to produce Vitamin D through synthesis.
quote: Signatures of Positive Selection in Genes Associated with Human Skin Pigmentation as Revealed from Analyses of Single Nucleotide Polymorphisms
KEYWORDS human pigmentation • skin color • positive selection • genetic adaptation • Perlegen database • SNP • EHH test 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.
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.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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quote:Rasol seemed to treat it like it DID negate back migration. My comment was sort of directed at that.
^ this is an example of a strawmen used to destract from an 'unpleasant' truth.
the study states that Africa is the *sole determinent* of diversity.
you try to run from this by introducing 'back migration' which by definition of what this study is saying -> is utterly irrelevant.
However you prove precisely why this factual study is necessary - to refute the bias, wishful thinking, and strawman arguments, such as proferred by you.
Ehh...ok. I admit to having a biased concept of "race." It isn't so much "wishful thinking" as it is my own logic. I guess, for the sole fact that I've witnessed features around me, I've associated certain ones with certain populations. "Wishful thinking" would imply that I really wished it were that way, but what would be the benefit of it being that way? What would be the benefit in an African American saying "certain populations look a certain way partially because of back migration?
Posts: 72 | Registered: Aug 2008
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quote:I guess, for the sole fact that I've witnessed features around me, I've associated certain ones with certain populations.
The simple notion that you continue to render certain features to be solely independent and specific to populations shows your limited understanding of what is discussed. Only thing unique to Europeans and East Asians is pale skin(besides albinos). Be specific in what features you mean.
Which is why you were asked to post/provide clear pictures/examples of individuals that you deem to look non African. Too much to ask??
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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quote:I guess, for the sole fact that I've witnessed features around me, I've associated certain ones with certain populations.
Which is why you were asked to post/provide clear pictures/examples of individuals that you deem to look non African. Too much to ask??
Well, to be honest, it would be foolish to say anyone from africa looks "non-African", but I could have pointed out those who, to my perception, look to have a Eurasian element. Notice I said "could have" since the more I read and the more people I see, the more the African and Non-African line becomes blurred. It would have been a person who looks like:
egyptian man
eritrean woman
eritrean kids
Again, I'm not so adament about my previous argument, but speaking from my own experience, and my own perception of "race" such people either look like "middle eastern peoples" or something like a "mulatto." Neither of which are terms that I like using, but phenotypically this is how I would mentally see them.
Posts: 72 | Registered: Aug 2008
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^^^^^This is a crucial situation and viewpoint to justify for you, since one can not always correlate genotype with phenotype. Would you be willing to establish as you stated the extreme features in these individuals that render them to look phenotypically non African influenced? It would be greatly appreciated.
One thing you have to understand is the near East was influenced not only linguistically but genotypically as well, from Africa, recently post OOA(Out Of Africa), so in a sense some features you might render as non African(since you're not familiar with the diversity of Africa) are actually due to African admixture in these near Easterners.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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quote:Originally posted by Knowledgeiskey718: The simple notion that you continue to render certain features to be solely independent and specific to populations shows your limited understanding of what is discussed. Only thing unique to Europeans and East Asians is pale skin(besides albinos). Be specific in what features you mean.
Honestly, it is not any one feature that I see as "specific to populations". It's a couple of co-existing features that have a tendancy, but I understand this is my way of trying to understand populations and "races." It is not accurate.
In the case of Africans, in acknowledgement of incredible diversity, I would not say that an african with a thin nose or lips or epicanthal folds had a non-african element, under certain conditions.
1. If they were not incredibly light skinned by my standards. 2. If the hair was not nearly straight. 3. If they were "far" from so called Non Sub-African populations, including North Africa
This is how I would have judged africans without stereotypically african features to determine whether there was a non Sub-saharan influence. I now know that this is pretty ridiculous, and it was not so imo until I physically typed my criteria. How's that for admitting to ignorance, inspite of reading to the contrary.? Perhaps the thing that made such thinking hard to abandon, particularly with criteria number 3 was the mtdna map of africa.
Posts: 72 | Registered: Aug 2008
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You say that the "pale phenotype" of Europeans and North East Asians derives from a recent mutation[actually it's 2 separate mutations].
So maybe you can explain why we have seemingly different allelic expressions of such? Southern Europeans and South East Asians are more pigmented than their more northerly neighbours--as if along some kind of gradient. The question is what is the basis for these mutations having such gradient-like allelic expressions? Example: A Cambodian or Thai is easily spotted in Beijing or Tokyo.
This goes back to my point, which is that mutations occur but it's rarely that you see sudden qualitative jumps from one phenotype to another. Which suggests that there are 2 ways intermediary phenotypes are expressed: one way is hybridity, another way is natural gradient change.
Example: many North Africans look like the offspring of Europeans and Africans but that does not mean that North Africans who have such phenotypes have resulted from some kind of back-migration of such types into Africa. It could just be a natural allelic variation of a particular mutation.
Point: to get to the desert from the forest you must pass through woods, savanah, then scrubland.
Puzzle: the pigmentation of many Africans, as in the case of the San, approximates that of Southern Europeans or South East Asian types.
Posts: 5492 | Registered: Nov 2004
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quote:Point: to get to the desert from the forest you must pass through woods, savanah, then scrubland.
^ It's true that to get from black to white you must past thru intermediate skin colors.
Actually the race paradigm holds that 'black' and 'white' are distinct sub-species - with no intrinsic relation to each other.
Anything that is not 'black' or 'white' would then be the result of mycengenation of the two.
This is incorrect.
What is correct:
- Original populations were melanoderms of Africa.
- Variations in dark skin tone is native to Africa with equatorial populations being darker, and southern temperate zone populations being lighter.
- This native potential for variation in skin color is the basis [root] of the variations that exist today all over the world.
- Original non African popoulations were melanoderms - descendant from equatorial east Africans.
- There skin color genotype and phenotype is best represented today by Melanesians, Oceanics, and Australians, as well as some South Asian and Polynesian populations.
- Northern Eurasians have experienced at least two independant instances of depigmentation - European and NorthEast Asian.
- Populations with with more intermediate skin colors - such as found in much of East Asia and parts of Southern Africa are not the product of myscegenation of 'black' and 'white'.
- Whites - ie leucoderms have provably limited genetic range and phenetic influence - primary restricted to influencing SouthWest Asia and parts of modern North Africa.
- It's unclear what influence they have had in India, and doubtful that they have ever had much influence in tropical Africa, East Asia, or Australia.
Posts: 15202 | Registered: Jun 2004
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quote:Originally posted by The Explorer: Doug, you know as a matter of fact, yes; one thing baffles me: the limitlessness of your stupidity.
Let's test who "lack of reading" makes a better fit...
You were supposedly attempting to correct someone else's short-sightedness by emphasizing "north Africa" even though the study deals with "all of Africa", only to replace it with your own:
If the study was focusing on "central and east Africa" as you say, how was that done so, vs. the rest of Africa?
Yes, your "finding specific patterns of diversity in central and southern Africa" would be a contradiction to your earlier "*specifically* central and eastern Africa" in two respects:
1)it doesn't say that the study is "specifically" about "central and southern Africa".
2)"central and southern Africa" is not the same as "central and east Africa".
And third, you read the abstract wrong; it makes reference to "central/southern Africa". "/" sign is not "and" in English grammar.
The point is you simply cannot read and are determined to use lack of reading comprehension as the reason exercise contradictions IN YOUR HEAD.
What I said:
quote: And it is not about Northern Africa it is about ALL of Africa and specifically places South of the Sahara like CENTRAL and EAST Africa. The GREATEST amount of diversity is found among the populations in this region and it is NOT simply those in East Africa, it is a reference to a BROAD RANGE of people from across Central Africa.
You just can't read. The only thing it says is that there is a broad range of diverse features among people all across central Africa. It means that you cannot stereotype East Africa as an isolated example of African diversity. It means that Africans all across Africa are diverse, but those in Central Africa, from East to West are more diverse and of course so are those to the South. But for some reason you cannot comprehend this.
Posts: 8893 | Registered: May 2005
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quote:I guess, for the sole fact that I've witnessed features around me, I've associated certain ones with certain populations.
Which is why you were asked to post/provide clear pictures/examples of individuals that you deem to look non African. Too much to ask??
Well, to be honest, it would be foolish to say anyone from africa looks "non-African", but I could have pointed out those who, to my perception, look to have a Eurasian element. Notice I said "could have" since the more I read and the more people I see, the more the African and Non-African line becomes blurred. It would have been a person who looks like:
egyptian man
eritrean woman
eritrean kids
Again, I'm not so adament about my previous argument, but speaking from my own experience, and my own perception of "race" such people either look like "middle eastern peoples" or something like a "mulatto." Neither of which are terms that I like using, but phenotypically this is how I would mentally see them.
And my point is that how common are the features of that woman in Eritrea, versus how common are the features of that male gentleman in Egypt? One or two pictures out of context do not mean anything. To study diversity one must have a LARGE SAMPLE of data in order to NOT BE BIASED.
YOU on the other hand take ONE example of the features in Eritrea and extrapolate that to mean that ALL Eritreans look like this and that ALL Eritreans are therefore mixed Eurasians. That is simply a DUMB STATEMENT. It is like taking a picutre of an Asian American and saying ALL AMERICANS are therefore mixed with Asians. YOU know this and this is why you keep repeating such nonsense. The point is that YOU have no idea what on earth you are talking about and are using HAND PICKED examples of possible Eurasian admixture to try and extrapolate WITHOUT EVIDENCE to support it. As I said, ONE or SOME Asian Americans in America does NOT make ALL Americans mixed with Asians. NO sort of population study EVER pretends that there aren't mixtures of various groups in one population to the next. What populations studies are looking for are patterns and percentages. The percentages of East Africans that are the result of mixing with Eurasians is relatively SMALL versus East Africans whose features are the result of INDIGENOUS African diversity.
The question is what do MOST Eritreans look like and what features do they have. MOST Eritreans are NOT mixed with Eurasians. Sure SOME of them may be, but that is NOT the basis of African diversity in features.
What about this Eritrean woman:
And the simple point is that people like these are where the Eurasians got their features from. The ONLY feature that Eurasians can give to Africans is light skin. Almost ALL OTHER features are indigenous to Africa.
Posts: 8893 | Registered: May 2005
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While you're obviously bent on suckering me into your infantile Micky Mouse games, as a means to avoid requests, I only have time for this:
Let's test your reading skills further, with this first...
What in the study says that "Central Africa and East Africa" [which you noticeably now changed to "Central Africa, from East to West"] is the most diverse in Africa?
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:Originally posted by The Explorer: While you're obviously bent on suckering me into your infantile Micky Mouse games, as a means to avoid requests, I only have time for this:
Let's test your reading skills further, with this first...
What in the study says that "Central Africa and East Africa" [which you noticeably now changed to "Central Africa, from East to West"] is the most diverse in Africa?
Dude. The only one playing mickey mouse games is you. I am not going to teach you how to read. So don't ask me.
Posts: 8893 | Registered: May 2005
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Not sure what lamin's comments on pigmentation has to do with the study's theme about the observed loss of intra-population cranio-metric diversity [and genetic diversity] in humans with augmentation of distance away from sub-Saharan Africa, but maybe he'll explain.
-------------------- 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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I ask this "know nothing about Africa but likes to talk about Africans" cry baby:
Let's test your reading skills further, with this first...
What in the study says that "Central Africa and East Africa" [which you noticeably now changed to "Central Africa, from East to West"] is the most diverse in Africa?
And his/her answer: I am not going to teach you how to read. So don't ask me.
Translation: I didn't read it anywhere.
"F minus" grade - you fail! Hence, answering my question, in that you are indeed a reading-challenged keyboard whiner.
-------------------- 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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All of it is diverse, with places LIKE Central being the most diverse. But that is not saying any one PART of central Africa is the most diverse. It only says that relative to ALL of Africa places like Central Africa are the most diverse. That is also what the study says.
posted
Why don't you go spam other threads with your usual "know nothing about Africans but obsessed with the dumb African" cry baby rants, since you are obviously intellectually useless to the topic here?
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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Punching more holes into the keyboard cry baby's "theory" as a self-proclaimed capable reader...
What in the study says that "Central Africa and East Africa" [which you noticeably now changed to "Central Africa, from East to West"] is the most diverse in Africa?
Why did you feel the need to separate East Africa in the former above, before you were forced to modify it to the latter?
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:Rasol seemed to treat it like it DID negate back migration. My comment was sort of directed at that.
^ this is an example of a strawmen used to destract from an 'unpleasant' truth.
the study states that Africa is the *sole determinent* of diversity.
you try to run from this by introducing 'back migration' which by definition of what this study is saying -> is utterly irrelevant.
However you prove precisely why this factual study is necessary - to refute the bias, wishful thinking, and strawman arguments, such as proferred by you.
quote:Why don't you go spam other threads with your usual "know nothing about Africans but obsessed with the dumb African" cry baby rants, since you are obviously intellectually useless to the topic here?
Wow, Ausarianstein this takes me back when I was chasing your dumb ass here.
quote:Posted by Lamin: So maybe you can explain why we have seemingly different allelic expressions of such? Southern Europeans and South East Asians are more pigmented than their more northerly neighbours--as if along some kind of gradient.
Damn kid you're a genius..........
Read again
quote:Originally Posted by Knowledgeiskey: Allow me to explain this is "laymen" terms. You're clearly speaking upon the pale phenotype of East Asians and Europeans (since you should already know cranio-facially/phenotypically speaking, Africa pretty much covers the world, I won't go into details on that) . This evolution/mutation is a recent adaptation, considering an evolutionary time line. This occurred due to the fact when humans move into northern latitudes need to be lighter skinned in order to allow UV in to produce Vitamin D(since dark skin was evolved to protect from harmful UV, therefore it prevents from absorbing UV to produce Vitamin D).
Early humans as well as early Europeans were hunter gatherers, in a hunter gatherers diet you will find food which contains adequate amounts of Vitamin D, through fish, meats, egg yolks etc... Absorbing enough of this Vitamin D will provide humans with enough Vitamin D to keep their skin dark with no need to be pale, since their receiving the Vitamin D through their diets. A clear example of a human population which consumes adequate amounts of vitamin d and retains melanin, are Eskimos. If you do some research you will notice that an Eskimos diet consists of rich amounts of Vitamin D, and if they would stop eating this diet, Eskimos would develop Vitamin D deficiencies, which surface as rickets, the reason for this is as explained, when humans move to northern latitudes/lower uv environments they aren't receiving as much sun(obviously) and since dark skin protects from harmful UV rays, it blocks out the ability to produce synthesize UV. The sun is one main source of Vitamin D along with diet. So in northern latitudes under a farmers diet(which doesn't provide an individual with adequate amounts of Vitamin D as a hunter gatherers diet would) humans would have to be lighter skinned, as explained, to allow the synthesis of UV for the production of Vitamin D, since dark skin blocks out the sun
Therefore, as explained light skin was evolved to allow the synthesis of Uv for the production of Vitamin d, but remember early Europeans were hunter gatherers, just as Eskimos are/were, so early Europeans retained their melanin levels as well, until agriculture spread. But agriculture /farming didn't spread into Europe until about 8kya with the Neolitic revolution. This new way of living decreased Europeans intake of vitamin D, since a farmers diet is not full with the adequate amounts of Vitamin D that a hunter gatherers fisher/herders diet consists of.
Therefore during this era, Europeans and East Asians evolved pale skin to allow UV in to produce Vitamin D through synthesis.
Posts: 6572 | From: N.Y.C....Capital of the World | Registered: Jun 2008
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In a related study conducted in 2007, the authors provide a map [see fig 2a; The Effects of ancient population bottlenecks on human phenotypic diversity] which details the "likely location for a single origin of craniometric phenotype assessed from concentration of diversity, and on it, that location was somewhere in what was enclosed in a light-shaded area demarcated by a dark blue line, almost akin to the above example about possible "point of origin of OOA migration". This enclosed area in fact extended as far as the Ivory Coast area in west Africa, proceeding to the central Africa, southeastern Africa through to southern Africa area. Interestingly, east Africa to as far as the African Horn was left outside of this loop, wherein it appears only Somalia area was sampled. For the genetic data though, attained from "neutral" atDNA markers, the map approximates that of the craniometric counterpart, but this time interestingly leaving southern Africa outside of the loop whilst including a portion of the African Horn.
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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AssOpen, do me a favor: take a hike, or better yet, take your voided skull to the now high-jacked Charlie Bass thread and continue spamming, opening your ass and whatever else it is that you do there.
-------------------- 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:Originally posted by The Explorer: Punching more holes into the keyboard cry baby's "theory" as a self-proclaimed capable reader...
What in the study says that "Central Africa and East Africa" [which you noticeably now changed to "Central Africa, from East to West"] is the most diverse in Africa?
Why did you feel the need to separate East Africa in the former above, before you were forced to modify it to the latter?
No what I said was you can't read. And you don't understand geography.
If you did you wouldn't be spamming your own thread with nonsense.
posted
keyboard cry baby, it looks like you love citing people drilling you with simple questions that you're too intellectually under-equipped to answer. You've probably never heard the word before or understood it, but such complete off-tangent panicky reaction to kindergarten level questions is called a "non-sequitur". So, why bother citing these simple questions?
-------------------- 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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posted
Interesting how the keyboard faux scholars only believe that Africans are diverse when it comes to mounting a desperate defense of the "Ancient Egyptians" be black or when someone claims that Ethiopians (Absynnia) are mixed.
The faux scholars attempt to have it both ways and therefore give the eurocentrics the proof they need to claim Ancient Egypt.
Afterall if the rest of Africans are mixed then why wouldn't Ethiopia and Ancient Egypt?
The faux scholars and their minimal intellect with its dependence on whites to do their research and science for them are just as destructive to Africa as the whites who control them.
Posts: 3085 | Registered: Jan 2008
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quote:gArgoyal writes: Interesting how the keyboard faux scholars only believe that Africans are diverse when it comes to mounting a desperate defense of the "Ancient Egyptians"
^ Interesting how you make strawman arguments, when you don't like the facts.
Actually it's not really interesting.
It's predictable and boring.
Address this..... We show that distance from sub-Saharan Africa is the sole determinant of human within-population phenotypic diversity, while climate plays no role.
No?
Why? Because you can't?
Then you're a weak troll trying to change the subject as beaten losers always do.
Posts: 15202 | Registered: Jun 2004
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Obviously this rasol was hit hard by my post that noticed how he and the rest of his fake scholars only defend or say anything positive about Africa if it involves anjuct ejupt.
He knows that his views that outside of Ancient Egypt he believes that Africa has or has achieved nothing.
Now he's kicking and screaming in dismay at my exposure of him. Too bad.
Posts: 3085 | Registered: Jan 2008
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posted
Boofer wrote: ------------------------------------ Again, I'm not so adament about my previous argument, but speaking from my own experience, and my own perception of "race" such people either look like "middle eastern peoples" or something like a "mulatto." Neither of which are terms that I like using, but phenotypically this is how I would mentally see them. ------------------------------------
Once again by your own statements, you are merely an intellectual unscholarly backwater who can't handle facts or evidence.
You instead need fantasy and delusions because that is what your tiny mind runs on.
Also since east africans are supposedly mixed with arabs and look like arabs you should have no problem of showing us actual examples of your belief.
quote:Not sure what lamin's comments on pigmentation has to do with the study's theme about the observed loss of intra-population cranio-metric diversity [and genetic diversity] in humans with augmentation of distance away from sub-Saharan Africa, but maybe he'll explain. --------------------------------------------------------------------------------
I mentioned pigmentation only because it is not significant than other traits in genetic analysis.
But again the analysis in the paper is suspect for the following reasons:
1) Craniometric analysis has had a long history--if only because it just involves measuring crania.
Now according to past studies it was found that the crania of Europeans fell into 3 categories: i)doliocephalic, ii)mesocephalic and iii) brachycephalic.
Nordics were measured as doliocephalic while Central Europeans were measured as mesocephlaic. East Europeans were measured as brachycephalic.
Now here's the rub: Africans in general were measured as primarily doliocephalic while East Asians were measured as brachycephalic. So obviously the diversity increased the further away from Africa one travelled with regard to Europe.
The explanation for the mesocephalic European crania was that the the bearers of such crania were hypbrids of northward migrating Africaoids and westward migrating Eastern Asiatics. The Nordics were supposed to have been too far north to be affected by such hybridisations.
Be that as it may, consider the following hypothesis: Think of Africa as the bicycle wheel with the myriad spokes representing migrations in all directions away from the East African human origins centre. Now if you take each spoke or a cluster of spokes as representing particular lineages then obviously you will have less diversity in any particluar limited area--as Europe proper, which is quite small in area[less than area of the Congo] compared to all of Africa.
The serious error made by Euro anthropologists is that they lump all of the African lineages together--hence you will get greater diversity while they become more specific for the separate areas outside of Africa.
Thus we end up under the illusion that "there is decreasing craniometric variation the further away from Africa one travels". But the same could be said for Africa too--the more one moves away from the central East African origin node.
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Saying that cranio-metric analysis has been around for long does not in any way discredit the study in question.
No, the study at hand does NOT just involve cranio-metric analysis as you say, it also involved DNA analysis.
Your caricatures about cranial indices are not only immaterial to said study, but also lack specificity of independent corroborative source. In fact they directly contrast the point relayed, with regards to African intra-population diversity being greater than that seen elsewhere.
Genetic diversity has nothing to do with the space of geography. It has to do with the simple fact that non-Africans derive from only a fraction of Africans, and hence, the loss of diversity that comes with that.
Losses in intra-population diversity [as observed in said study] with accruement of distance away from sub-Saharan Africa is very likely the effect of further offshoots from OOA migrants and subsequent dispersals, and hence, bottlenecks that generally characterize such events.
Sorting out intra-population diversity requires precisely the opposite of "lumping" specimens together. Pooling specimens together generally has the effect of *obscuring* intra-specimen variation.
Queries for clarification:
Explain how the findings of the said study about loss of intra-population craniometric and genetic diversity with accruement of distance away from sub-Saharan Africa is an "illusion" and not a tangible phenomenon.
Given the maps posted above and as noted, in a related study conducted in 2007, the authors provide a map [see fig 2a; The Effects of ancient population bottlenecks on human phenotypic diversity] which details the "likely location for a single origin" enclosed in an un-shaded area that spans west Africa to as far as Ivory Coast, central Africa, south-eastern Africa and southern Africa area, where is it stated in the study, that "central East Africa" is the origin node?
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I mentioned pigmentation only because it is not significant than other traits in genetic analysis.
How does skin color change the patterns observed in intra-population diversity?
Posts: 7516 | From: Somewhere on Earth | Registered: Jan 2008
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quote:Not sure what lamin's comments on pigmentation has to do with the study's theme about the observed loss of intra-population cranio-metric diversity [and genetic diversity] in humans with augmentation of distance away from sub-Saharan Africa, but maybe he'll explain. --------------------------------------------------------------------------------
I mentioned pigmentation only because it is not significant than other traits in genetic analysis.
But again the analysis in the paper is suspect for the following reasons:
1) Craniometric analysis has had a long history--if only because it just involves measuring crania.
Now according to past studies it was found that the crania of Europeans fell into 3 categories: i)doliocephalic, ii)mesocephalic and iii) brachycephalic.
Nordics were measured as doliocephalic while Central Europeans were measured as mesocephlaic. East Europeans were measured as brachycephalic.
Now here's the rub: Africans in general were measured as primarily doliocephalic while East Asians were measured as brachycephalic. So obviously the diversity increased the further away from Africa one travelled with regard to Europe.
The explanation for the mesocephalic European crania was that the the bearers of such crania were hypbrids of northward migrating Africaoids and westward migrating Eastern Asiatics. The Nordics were supposed to have been too far north to be affected by such hybridisations.
Be that as it may, consider the following hypothesis: Think of Africa as the bicycle wheel with the myriad spokes representing migrations in all directions away from the East African human origins centre. Now if you take each spoke or a cluster of spokes as representing particular lineages then obviously you will have less diversity in any particluar limited area--as Europe proper, which is quite small in area[less than area of the Congo] compared to all of Africa.
The serious error made by Euro anthropologists is that they lump all of the African lineages together--hence you will get greater diversity while they become more specific for the separate areas outside of Africa.
Thus we end up under the illusion that "there is decreasing craniometric variation the further away from Africa one travels". But the same could be said for Africa too--the more one moves away from the central East African origin node.
I agree with you lamin. Can anyone post the entire study so we can really see what it contains. An abstract can not really give us a full discussion of the material printed in the article. This is due to the fact that diversity in craniometrics in Africa has always been the case .
quote:Originally posted by Clyde Winters: Can anyone post the entire study so we can really see what it contains. An abstract can not really give us a full discussion of the material printed in the article. This is due to the fact that diversity in craniometrics in Africa has always been the case .
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Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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quote:Originally posted by Clyde Winters: Can anyone post the entire study so we can really see what it contains. An abstract can not really give us a full discussion of the material printed in the article. This is due to the fact that diversity in craniometrics in Africa has always been the case .
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Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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-------------------- 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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-------------------- 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
The researchers' choice of skulls no more than 2,000 years old would tend to bias results it seems. There have been many population movements in the world from at least 2,000 YA. East-West and North-South movements on the Eurasian landmass are very obvious cases. Europe's perpetual wars and invasions in the last 2,000 years no doubt would not help the researchers hypothesis. After all, as I mentioned, the craniometric data from Europe shows heterogeneous results from region to region--using the old model of doliocephalic, mesocephalic, brachycephalic.
In sum, the paper yields a mixed bag of results--nothing definite. Though it is noted that the mutiregional hypothesis is mentioned--despite its lack of substance.
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quote:In sum, the paper yields a mixed bag of results--nothing definite.
How so?
quote:The researchers' choice of skulls no more than 2,000 years old would tend to bias results it seems
Why?
quote:. Europe's perpetual wars and invasions in the last 2,000 years no doubt would not help the researchers hypothis
Why? All regions have -perpetual wars- that doesn't explain the results.
quote:After all, as I mentioned, the craniometric data from Europe shows heterogeneous results from region to region--using the old model of doliocephalic, mesocephalic, brachycephalic
What study can you reference?
What study can refute the results of this one?
quote:mentioned--despite its lack of substance.
Your post consists of ad hoc conclusions - backed by nothing.
Where is the substance behind your claims?
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posted
Beat me to it. Not sure what Lamin is saying. How about some deeeep analysis Lamin? If you are not sure what to make of it. Take your time and read it several times.. . . then respond.
-------------------- 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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Your reckoning that population movements in the last 2,000 years is supposed to be cause for biased results has no merit. Whom is it supposed to be biased against and vice versa? And why?
The authors could well have taken crania from 10,000 years ago, it won't make it any less bias, because populations from that time frame too would have been in movement. Name a time frame when population movements had not occurred, whether within or outside of the African continent, and give me the statistics on the sample size of specimens from that era.
Repeating some *immaterial* claim [which has already been called out above at any rate, with no forthcoming answers from you in sight] about cranial indices, supposedly to point out diversity in Europe, serves what purpose?
Lay out this "mixed bag of results" that you talk of, when in fact the authors have provided us with a *definite result*, which is:
Greatest intra-population diversity in sub-Saharan Africa vs. that elsewhere, and that it [intra-population] decreases with distance incrementation away from sub-Saharan Africa. This parallels what they observed from DNA analysis!
Clyde,
If you agree with lamin and not merely a cheerleader, then perhaps you should answer the questions and issues he left unanswered...which is virtually *all* of the ones I directed at him.
xyyman,
The study you posted is a related one from 2007 by the very same authors, on essentially the same subject matter; however, the abstract in the head post of this thread is from December 3rd 2008!
-------------------- 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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The title is "The effect of ancient population bottlenecks on human phenotypic variations.
So if ancient bottlenecks why limit the study to crania no more than 2,000 years old? We know that in the last 2,000 years worldwide there have been significant population movements which would mean some amount of transpopulation genetic exchange. Think of Genghis Khan and his cohorts expanding into Europe proper all the way from Central Asia. Think too of the Northern European barbarians invading Rome and elswhere in Europe. The European crusades into West Asia, the Turkish invasions into North Africa and Europe all led to new population transfers and genetic exchange, etc.
The Multiregional hypothesis pushed by researchers like Wolpoff et al.[1992] and others is based mainly on physical anthropological data rather than DNA analysis. It has very few adherents these days--except those who want to establish great genetic distance between the so-called races.
Note that the authors of the paper speak of ancient bottlenecks which would mean populations that have bootlenecked off a parent population and have multiplied mainly among themselves in relative isolation.
I stated that the hypothesis of the paper would be at variance with this because in the last 2,000 years--on account of wars and invasions--across the Eurasian plains and along the north-south latutudes of Europe and elsewhere, old bootlenecked populations would have experienced much commingling with other populations.
Note too that blog exchanges such as those ES, etc. only require the quick exchange of ideas without the citing of references--which would be more appropriate for specialist academic blog sites. Which is not to deny that references are sometimes useful when there is some clear point of dispute.
It looks like the title of the article does not reflect its contents.
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I looked at the papers numbers and they do not demsonstrate any significant support its claims. What the authors fail to recognise in their appeal to a vast area such as so-called "sub-Saharan" Africa is that the distance from the Cape of Good Hope to Mali in West Africa is greater than the distance from Mali to Italy. The distance from Senegal to Mombassa is greater than the distance from Sudan to Turkey.
So what is the point of using "sub-Saharan" Africa as a nodal point of departure for the analysis.
Surely, there must have been "ancient bottlenecks" formed in so-called "sub-Saharan Africa".
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Population movements have been more pronounced in the last 2,000 years than previously because of more efficient means of transportation and greater increases in population worldwide.
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