posted
As some posters already noticed, most of the physical attributes that define so called "Caucasoid", "Mongoloid" or "Negroid", are all found in Africa. However I keep reading in Scientif studies even quoted here by well informed posters things like East Asian have high cheek bones because they had to protect themselves from the weather, the shape of their eyes was an adaptation to the weather. The same arguments are made for Eurasians, the shape of their nose is due to adaptation to cold weather so the cool hair become warmer when it enters the nasal orifices. Where do we stop? a more reasonable assumption is that Africans with different physical features left Africa and colonized the world, in some places they had features similar to diminutive people of Africa: like in NPG and Australia, in other places they had features similar to Sans or Elongated Eastern Africans. On this forum we went over Eastern Elongated, and how some Non African might have inherited their features along with more broad faced African phenotypes, however the fact that East Asian phenotype might be derived from San looking people is always ignored and as I mentioned earlier some speculations are advance concerning their phenotypes as if early Africans didn't contribute to them: The Sans
Relaxx
[This message has been edited by relaxx (edited 24 October 2005).]
It is more likely that the first Out-of-Africans were homogeneous in phenotypical traits; however they did have the genetic potential to alter such traits via natural selection according to the environment.
Thus cold-adapted people are very fair-skinned even though the first OOAs were not.
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It is more likely that the first Out-of-Africans were homogeneous in phenotypical traits; however they did have the genetic potential to alter such traits via natural selection according to the environment.
Thus cold-adapted people are very fair-skinned even though the first OOAs were not.
Thanks for replying, I was talking about other features and not the skin color, since they were many waves over thousand years, it's dangerous to assume that they were "homogeneous in phenotypical traits". Africans started to leave Africa 60K years ago, but they had lived almost 140k years, don't you think by that time they were diverse phenotypically? I still don't buy that physical features outside Africa beside the hair and the color of the skin is indigenous, and evolved locally, they were derived from African phenotypes. Relaxx
[This message has been edited by relaxx (edited 24 October 2005).]
quote:Originally posted by Djehuti: ...they did have the genetic potential to alter such traits via natural selection according to the environment.
Thus cold-adapted people are very fair-skinned even though the first OOAs were not.
Yeap; phenotyptic similarities can be either through gene flow, or happenstance [via in situ evolution due to genetic mutations and natural selection], or a combination of both.
quote:Originally posted by relaxx: Thanks for replying, I was talking about other features and not the skin color, since they were many waves over thousand years, it's dangerous to assume that they were "homogeneous in phenotypical traits". Africans started to leave Africa 60K years ago, but they had lived almost 140k years, don't you think by that time they were diverse phenotypically? I still don't buy that physical features outside Africa beside the hair and the color of the skin is indigenous, and evolved locally, they were derived from African phenotypes. Relaxx
But the same goes with other features! According to genetic studies, OOAs were a small population and most likely the same in features. What you fail to realize is that the diversity in features (not just skin color) developed as a result of evolution. The original OOA population could have all had the same features, but genetically they had enough variation to produce different features as their descendants evolved to different environments.
[This message has been edited by Djehuti (edited 25 October 2005).]
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quote:Originally posted by Djehuti: But the same goes with other features! According to genetic studies, OOAs were a small population and most likely the same in features. What you fail to realize is that the diversity in features (not just skin color) developed as a result of evolution. The original OOA population could have all had the same features, but genetically they had enough variation to produce different features as their descendants evolved to different environments.
[This message has been edited by Djehuti (edited 25 October 2005).]
Djehuti, As is stated in the following paragraph, there was two waves out of Africa: 60,000 years ago and 45,000 years ago, it is possible that Africans from those waves were phenotipically different and thus influenced greatly the present phenotypes of Non Africans in terms of body size, facial features and other traits beside the skin color and the hair texture which are really the main traits that are distinct from the average native African phenotypes :
Current DNA-based techniques can trace the lineage of Homo sapiens back 200,000 years ago to Africa. Although Wells marshals evidence from diverse fields of enquiry to his task of tracing human origins, he primarily writes about a stunning new array of genetic explorations in the last two decades. By tracking a genetic marker called M-168 that is present in the Y-chromosomes of men, Wells demonstrate how the first bands of modern humans, perhaps not unlike present-day African "bushmen", moved out of Africa and colonised the Arabian peninsula about 60,000 years ago. Almost immediately, a sub-group bearing the genetic marker M-130 rapidly moved along the resource-rich coastal fringe of southern Asia, populating Southeast Asia and Australia within a few thousand years. Because of lower sea level that prevailed, the Asian coastline was aligned very differently with far greater connectivity among landmasses, facilitating the rapid migration of M-130 lineage. These people were ancestors to the aboriginal human groups of Australia as well as in south and south-eastern Asia.
Another branch off the M-168 colonisers that bore the genetic marker M-89 moved into middle-east (45,000 years ago) and gave rise to lineage M-9 that moved into southern part of central Asia (40,000 years ago), following teeming herds of game in those vast grasslands. The M-9 lineage subsequently forked out in three directions: M-45 penetrated deeper into central Asia 35,000 years ago; M-175 moved into the Tibet-southern China region 30,000 years ago and a population bearing the genetic marker M-20 moved into the Indian subcontinent. This M-20 lineage intermixed with the earlier coastal migrant populations of M-130. Based on genetic evidence, Wells suggests the encounter between these groups may have been brutal and one-sided, with most men of the M-130 lineage being eliminated and their women being interbred with the more "advanced" (read aggressive) M-20 lineage. Thus, clearly all modern south Asians are a "genetic cocktail" of at least 30,000-year vintage, not withstanding notions of "superiority by birth" promoted by assorted swamis, acharyas, jagadgurus, and mullahs who proliferate in India, Sri Lanka, Pakistan and Bangladesh now. The biological evidence shows that their culturally inspired notions of "different blood" coursing through the veins of Hindus, Buddhists, Muslims, Dalits or whoever else, are absurd.
This human odyssey continued across the earth. The bearers of the marker M-242, descendants of M-45, advanced across the frozen north Asian continent, adapting to ice-age conditions to hunt woolly mammoths. They colonised the "new world" 20,000 years before Christopher Columbus "discovered" it. Within a few thousand years, these original Americans had spread all the way to the tip of South America. Around the same time, racing across China was a group of people bearing the marker M-122, descendants of M-175, who eventually populated much of Southeast Asia.
About 10,000 years ago, as ice-sheets retreated across Europe and Northern Asia, modern humans bearing genetic marker M-172 moved into Europe. The warm-moist climatic regime that we now live in emerged. The earth was already peopled, and ready for the next human revolution: discovery of agriculture and the consequent ability to modify the environment itself, unlike any other creature before.
Wells synthesises the genetic evidence with current research in geology, palaeontology, archaeology, anthropology and linguistics to make a robust case for his account of the human journey. A Harvard-trained expert on human evolution, Wells peppers his narrative with stories of major scientific breakthroughs along the way, ranging from insights of pioneers like Charles Darwin and Paul Broca to findings of modern-day scientists like Luigi Calvelli-Sforza, Richard Lewontin, Rebecca Caan and others. The book is nicely illustrated with a series of line drawings and range maps. Photographer Mark Reads' remarkable portfolio of human-cultures significantly enriches the text, although the numerically abundant and highly varied southern Asian cultures appear to be under-represented in it.
[This message has been edited by relaxx (edited 25 October 2005).]
posted
The above is referenced from Spencer Wells Journey of Man.
I'm not sure Wells exactly supports your thesis though, for example he uses the Khoisan as a base population prototype for all non Africans - and since M168/M9 derived lineages define both Chinese and Swiss [for example] you would still have to account for differences in phenotypes emerging after ROA.
That is - did the 1st M9 populations have ephicanthic folds, like the Chinese? Or not....like the Swiss?
Still your theory is interesting. Good thread.
[This message has been edited by rasol (edited 25 October 2005).]
quote:Originally posted by rasol: The above is referenced from Spencer Wells Journey of Man.
I'm not sure Wells exactly supports your thesis though, for example he uses the Khoisan as a base population prototype for all non Africans - and since M168/M9 derived lineages define both Chinese and Swiss [for example] you would still have to account for differences in phenotypes emerging after ROA.
That is - did the 1st M9 populations have ephicanthic folds, like the Chinese? Or not....like the Swiss?
Still your theory is interesting. Good thread.
[This message has been edited by rasol (edited 25 October 2005).]
Correct Rasol it's from the Journey of Man, but as you know different human groups with different phenotypes can share the same lineage, a typical example is the Hutus, Tutsis and Twa from the Central Africa. I think Djehuti might want to comment on that. Relaxx
quote:Originally posted by relaxx: Correct Rasol it's from the Journey of Man, but as you know different human groups with different phenotypes can share the same lineage, a typical example is the Hutus, Tutsis and Twa from the Central Africa.
Yes but if we are using ephicanthic folds as an example, the case would still be that the initial group either:
a) all had epicathnic folds. b) did not have them. or... c) some had them and some didn't.
Subsequent to migrating out of Africa you have two distinct groups - Europeans without epicanthic folds, and East Asians with them.
This implies to most anthropologists that current phenotypes developed - post - separation of East Asians and Europeans.
One of the reasons that this is suggested is that there is little to no evidence of these distinct Northern Eurasian phenotypes among the Earliest Out of Africa populations - moreover until this populations migrate into Northern Eurasia, there is no 'impetus' for the development of some distinct traits - for example pale skin in Europeans, or polar [cold adapted] limb ratios and sub-cutaneous fat in East Asians.
Finally, keep in mind Chris Stringers findings on early European populations, sometimes called cro-magnon: some were more like modern Africans and Australians based on objective anatomical measurements.
One thing is clear...it's a complicated picture.
[This message has been edited by rasol (edited 25 October 2005).]
quote:Originally posted by rasol: Yes but if we are using ephicanthic folds as an example, the case would still be that the initial group either:
a) all had epicathnic folds. b) did not have them. or... c) some had them and some didn't.
Subsequent to migrating out of Africa you have two distinct groups - Europeans without epicanthic folds, and East Asians with them.
This implies to most anthropologists that current phenotypes developed - post - separation of East Asians and Europeans.
One of the reasons that this is suggested is that there is little to no evidence of these distinct Northern Eurasian phenotypes among the Earliest Out of Africa populations - moreover until this populations migrate into Northern Eurasia, there is no 'impetus' for the development of some distinct traits - for example pale skin in Europeans, or polar [cold adapted] limb ratios and sub-cutaneous fat in East Asians.
Finally, keep in mind Chris Stringers findings on early European populations, sometimes called cro-magnon: some were more like modern Africans and Australians based on objective anatomical measurements.
One thing is clear...it's a complicated picture.
[This message has been edited by rasol (edited 25 October 2005).]
In his approach, Spencer Wells seem to favor a) over b) and c), however, the earliest Africans who left the continent could have been San looking people or a mix with other Africans with different phenotypes but who share the oldest lineages. Or it's possible that San looking people only left in the second wave along with other Africans since we don't observe their phenotype in Australia and NPG where the fist humans went. Remember that as of today the majority of people who live in North East and East Africa are Nilotes (Southern Sudanese) and Cushitic speaking people who also have very old lineages, and probably San looking people where also numerous. That's why c) is a plausible candidate, since Upper Paleolithic European had phenotypes similar to modern Africans and Australians. But you’re correct it’s very complicate even if we observe similar phenotypes between Africa and other continents. It will remain that way as long as Scientists can’t explain precisely the relationship between adaptation to climate and phenotype. Relaxx
quote:Originally posted by relaxx: Djehuti, As is stated in the following paragraph, there was two waves out of Africa: 60,000 years ago and 45,000 years ago, it is possible that Africans from those waves were phenotipically different and thus influenced greatly the present phenotypes of Non Africans in terms of body size, facial features and other traits beside the skin color and the hair texture which are really the main traits that are distinct from the average native African phenotypes :
Current DNA-based techniques can trace the lineage of Homo sapiens back 200,000 years ago to Africa. Although Wells marshals evidence from diverse fields of enquiry to his task of tracing human origins, he primarily writes about a stunning new array of genetic explorations in the last two decades. By tracking a genetic marker called M-168 that is present in the Y-chromosomes of men, Wells demonstrate how the first bands of modern humans, perhaps not unlike present-day African "bushmen", moved out of Africa and colonised the Arabian peninsula about 60,000 years ago. Almost immediately, a sub-group bearing the genetic marker M-130 rapidly moved along the resource-rich coastal fringe of southern Asia, populating Southeast Asia and Australia within a few thousand years. Because of lower sea level that prevailed, the Asian coastline was aligned very differently with far greater connectivity among landmasses, facilitating the rapid migration of M-130 lineage. These people were ancestors to the aboriginal human groups of Australia as well as in south and south-eastern Asia.
Another branch off the M-168 colonisers that bore the genetic marker M-89 moved into middle-east (45,000 years ago) and gave rise to lineage M-9 that moved into southern part of central Asia (40,000 years ago), following teeming herds of game in those vast grasslands. The M-9 lineage subsequently forked out in three directions: M-45 penetrated deeper into central Asia 35,000 years ago; M-175 moved into the Tibet-southern China region 30,000 years ago and a population bearing the genetic marker M-20 moved into the Indian subcontinent. This M-20 lineage intermixed with the earlier coastal migrant populations of M-130. Based on genetic evidence, Wells suggests the encounter between these groups may have been brutal and one-sided, with most men of the M-130 lineage being eliminated and their women being interbred with the more "advanced" (read aggressive) M-20 lineage. Thus, clearly all modern south Asians are a "genetic cocktail" of at least 30,000-year vintage, not withstanding notions of "superiority by birth" promoted by assorted swamis, acharyas, jagadgurus, and mullahs who proliferate in India, Sri Lanka, Pakistan and Bangladesh now. The biological evidence shows that their culturally inspired notions of "different blood" coursing through the veins of Hindus, Buddhists, Muslims, Dalits or whoever else, are absurd.
This human odyssey continued across the earth. The bearers of the marker M-242, descendants of M-45, advanced across the frozen north Asian continent, adapting to ice-age conditions to hunt woolly mammoths. They colonised the "new world" 20,000 years before Christopher Columbus "discovered" it. Within a few thousand years, these original Americans had spread all the way to the tip of South America. Around the same time, racing across China was a group of people bearing the marker M-122, descendants of M-175, who eventually populated much of Southeast Asia.
About 10,000 years ago, as ice-sheets retreated across Europe and Northern Asia, modern humans bearing genetic marker M-172 moved into Europe. The warm-moist climatic regime that we now live in emerged. The earth was already peopled, and ready for the next human revolution: discovery of agriculture and the consequent ability to modify the environment itself, unlike any other creature before.
Wells synthesises the genetic evidence with current research in geology, palaeontology, archaeology, anthropology and linguistics to make a robust case for his account of the human journey. A Harvard-trained expert on human evolution, Wells peppers his narrative with stories of major scientific breakthroughs along the way, ranging from insights of pioneers like Charles Darwin and Paul Broca to findings of modern-day scientists like Luigi Calvelli-Sforza, Richard Lewontin, Rebecca Caan and others. The book is nicely illustrated with a series of line drawings and range maps. Photographer Mark Reads' remarkable portfolio of human-cultures significantly enriches the text, although the numerically abundant and highly varied southern Asian cultures appear to be under-represented in it.
Actuallly Relaxx, if you payed close attention you would see that those populations that began colonizing the rest of Eurasia around 45,000 years ago are descended from the SAME M-168 carrying OOA population. There was no second wave, at least by Wells studies!
[This message has been edited by Djehuti (edited 26 October 2005).]
Posts: 26245 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: Actuallly Relaxx, if you payed close attention you would see that those populations that began colonizing the rest of Eurasia around 45,000 years ago are descended from the SAME M-168 carrying OOA population. There was no second wave, at least by Wells studies!
[This message has been edited by Djehuti (edited 26 October 2005).]
And from Underhill et al.: "Posterior demic movements, such as the one represented by the dissemination of the ancestral M89 chromosomes and the 10873T mtDNA lineage to Eurasia, most likely occurred via the Levantine corridor, ~45 ky ago (Underhill et al. 2001b; Quintana-Murci et al. 1999).". However M130 spread via the Southern Arabia Peninsula 60K years go, it seems that there were two distinct waves out of Africa even though their ancestors carried M168. Scientists carefully describe M89 and M130 as markers that identify people who left Africa respectively 45K and 60K years ago. Meaning those markers could have arisen in Africa and then spread outside Africa. Relaxx
Relaxx
[This message has been edited by relaxx (edited 26 October 2005).]
And from Underhill et al.: "Posterior demic movements, such as the one represented by the dissemination of the ancestral M89 chromosomes and the 10873T mtDNA lineage to Eurasia, most likely occurred via the Levantine corridor, ~45 ky ago (Underhill et al. 2001b; Quintana-Murci et al. 1999).". However M130 spread via the Southern Arabia Peninsula 60K years go, it seems that there were two distinct waves out of Africa even though their ancestors carried M168. Scientists carefully describe M89 and M130 as markers that identify people who left Africa respectively 45K and 60K years ago. Meaning those markers could have arisen in Africa and then spread outside Africa. Relaxx
Relaxx
Didn't Dr. Wells say that M89 carriers divereged from the same ancestral population as the M130 carriers, and that this ancestral population was a single population already settled in Southern Arabia??
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quote:Originally posted by Djehuti: Didn't Dr. Wells say that M89 carriers divereged from the same ancestral population as the M130 carriers, and that this ancestral population was a single population already settled in Southern Arabia??
Here is another quote: 'The Middle Eastern marker, M89, represents a wave of migration out of Africa that occurred around 45,000 years ago. The Haplogroup R lineage ultimately traces all the way back to marker M168.
"Every non-African has M168, which appeared in eastern Africa around 60,000 years ago," Wells said.'
posted
Here is another quote: 'The Middle Eastern marker, M89, represents a wave of migration out of Africa that occurred around 45,000 years ago. The Haplogroup R lineage ultimately traces all the way back to marker M168.
"Every non-African has M168, which appeared in eastern Africa around 60,000 years ago," Wells said.'
And the following is even more precise: The third large sub-cluster of M168 lineages is characterized by the M89/M213 mutations at the root of Groups VI-X. As discussed above, this sub-cluster is suggested to have evolved in East Africa, from where it dispersed to Eurasia through the Levantine corridor around 45000 years ago. This dispersal would have also involved several mtDNA haplogroups characterized by the 10873 C -->T mutation (Quintana-Murci et al. 1999)." (Underhill, 2001) Relaxx
quote:Originally posted by relaxx: Here is another quote: 'The Middle Eastern marker, M89, represents a wave of migration out of Africa that occurred around 45,000 years ago. The Haplogroup R lineage ultimately traces all the way back to marker M168.
"Every non-African has M168, which appeared in eastern Africa around 60,000 years ago," Wells said.'
And the following is even more precise: The third large sub-cluster of M168 lineages is characterized by the M89/M213 mutations at the root of Groups VI-X. As discussed above, this sub-cluster is suggested to have evolved in East Africa, from where it dispersed to Eurasia through the Levantine corridor around 45000 years ago. This dispersal would have also involved several mtDNA haplogroups characterized by the 10873 C -->T mutation (Quintana-Murci et al. 1999)." (Underhill, 2001) Relaxx
I've seen the program Journey of Man on PBA and it showed that the population that spread to northern Eurasia 45000 years ago was a branch of the same population that generated the branch that migrated through the coastal areas 60,000 years ago.
The maps you showed indicate this and not two entirely seperate waves out of Africa but a single wave that divided into 2.
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