posted
I have not read the article, but you might find it interesting. The article is two parts, a letter and a responce. -----------
Science 6 April 2007: Vol. 316. no. 5821, pp. 50 - 53 Letters
Timing of a Back-Migration into Africa
Indigenous North Africans are genetically quite distinct from sub-Saharan Africans (1), and this difference is reflected in their lighter skin and European/Middle Eastern physical features. We have previously suggested, on the basis of the distribution of mtDNA type M1, that North Africans are largely descended from a back-migration into Africa within the last 2000 to 15,000 years, resettling the temporarily lush Sahara and spreading the Afro-Asiatic language family (2). In their Report "The mtDNA legacy of the Levantine early Upper Palaeolithic in Africa" (15 Dec. 2006, p. 1767), A. Olivieri and colleagues used high-resolution mtDNA data to propose that the migration from Asia back to North Africa happened much earlier, and they link the settlement of North Africa with the settlement of Europe 40,000 to 45,000 years ago.
Three points lead us to believe that our younger chronology for the back-migration into northern Africa still merits consideration. First, the mtDNA trees reconstructed by Olivieri and colleagues are less than conclusive because they consist of phylogeographically mixed branches, which cause uncertainty in identifying the relevant founder nodes for genetic dating. Second, in our view the fact that the North African mtDNA marker types still correspond so closely with the Afro-Asiatic language zone argues against the existence of that correlation for tens of thousands of years. Third, cave art in the Sahara shows that in Neolithic times (around 5000 B.C.), the population of the Sahara was still of sub-Saharan African ancestry (see figure), whereas "Europoid" figures documenting the arrival of west Eurasians appear later in the cave art record (3).
Within the framework of our younger chronology, the occurrence of low frequencies of M1 types in the European Mediterranean can be explained by diffusion from the Middle East and North Africa during and since the Neolithic. The Sardinian M1 mtDNA founder date of 7700 ± 3100 years years calculated by Olivieri and colleagues would conveniently fit with the arrival of farming in the European Mediterranean.
In conclusion, we suggest that more recent influx from Asia, possibly since the Last Glacial Maximum 20,000 years ago, may better explain some of the major genetic and linguistic patterns in North Africa and adjacent areas [cf. (4, 5)]. We nevertheless believe that future archaeogenetic research on Ice Age Africa and subsequent periods will benefit greatly from the complete mtDNA sequencing approach taken by Olivieri and colleagues.
Peter Forster* Department of Forensic Science and Chemistry Anglia Ruskin University, Cambridge CB1 1PT, UK and New Hall, University of Cambridge Cambridge CB3 0DF, UK
*To whom correspondence should be addressed. E-mail: pf223@cam.ac.uk
Valentino Romano Dipartimento di Oncologia Sperimentale e Applicazioni Cliniche Università di Palermo Palermo, Italy and Associazione OASI Maria SS. (I.R.C.C.S.) Troina, Italy
References
1. L.-L. Cavalli-Sforza, P. Menozzi, A. Piazza, The History and Geography of Human Genes (Princeton Univ. Press, Princeton, NJ, 1994). 2. P. Forster, Philos. Trans. R. Soc. London Ser. B 39, 255 (2004). 3. A. Muzzolini, L'Art Rupestre Prehistorique des Massifs Centraux Sahariens (BAR, Oxford, 1986). 4. C. Renfrew, Cambr. Archaeol. J. 1, 3 (1991). 5. I. Diakonoff, J. Semit. Stud. 43, 209 (1998).
Response
The principal problem with great syntheses of languages, genes, and figurines (or pots) is that they lump together different migrational and cultural processes and especially overstretch recent events of the Holocene, thereby downplaying or swamping the genetic signals that point to much earlier events of the Pleistocene (1, 2).
Forster and Romano propose a recent arrival--within the last 2000 to 15,000 years--of haplogroup M1 in North Africa from western Asia, linked to the spread of Afro-Asiatic languages. This would entail a Near Eastern origin of the Afro-Asiatic language family and thus would be in agreement with Bellwood (3), provided that one subscribes to such a tight link between genes and languages. Afro-Asiatic scholarship (4), as well as the coalescence times of both M1a and M1b and the diverse basal distribution of M1a lineages especially in East Africa, however, militate against this interpretation. As we proposed in our Report, the arrival of M1 in Africa is most likely contemporary with that of U6, but if one alternatively hypothesized that only M1a originally went into the Northeast African Mediterranean coast, then 25,000 to 30,000 years ago would be the realistic time frame.
The latter hypothesis is valid when one assumes the less parsimonious scenario that only haplogroup U6 was involved 40,000 to 45,000 years ago in the early Upper Palaeolithic diffusion of Levantine populations into North Africa and that a diffusion of M1a lineages marked a new phase in the Nile Valley Complex, 25,000 to 30,000 years ago (5). It is then also more plausible to see the development and emergence of proto-Afro-Asiatic languages there, in the Nile Valley (6, 7). Later migrations and gene flow, which undoubtedly took place, have certainly complicated phylogeographic patterns. For instance, one may also envision some mutual contacts between the Levantine Natufian culture and contemporary autochthonous cultures of the Lower Nile Valley (~15,000 years ago). Later Neolithic influence then brought a whole package of Near Eastern mtDNA lineages into all of North Africa, as attested, for instance, by the relatively high frequency of mtDNA haplogroups H, J, and T in modern North African populations (8, 9).
The cave art argument adduced by Forster and Romano has no impact on the issue of the late Near Eastern influx because haplogroup U6 very clearly testifies to an early presence in North Africa of Near Eastern lineages, which must have proceeded to as far as Northwest Africa with the ancestors of the Iberomaurusians before the Late Glacial Maximum (8). The anthropological evidence from North Africa, pointing to the autochthonous Mechta-Afalou physical type, with continuity well into the Capsian of the mid-Holocene, gives clear support to the ancient presence of Upper Palaeolithic people in North Africa (5). Moreover, the presence of figurines of sub-Saharan type in the cave art of the Sahara may simply be indicative of resettlement of the region by groups from the south, already adapted to savannah ecology, after the early Holocene arrival of monsoon rains changed the Sahara into a habitable region (10). Thus, the argument is not informative on the antiquity of a "Europoid" settlement in North Africa.
Anna Olivieri Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Alessandro Achilli Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Maria Pala Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Vincenza Battaglia Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Simona Fornarino Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Nadia Al-Zahery Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Department of Biotechnology College of Science University of Baghdad, Iraq
Rosaria Scozzari Dipartimento di Genetica e Biologia Molecolare Università "La Sapienza," Piazzale Aldo Moro 5 00185 Rome, Italy
Fulvio Cruciani Dipartimento di Genetica e Biologia Molecolare Università "La Sapienza," Piazzale Aldo Moro 5 00185 Rome, Italy
Doron M. Behar Molecular Medicine Laboratory Rambam Health Care Campus Efron 9 street, Bat Galim 31096 Haifa, Israel
Jean-Michel Dugoujon Centre d'Anthropologie, FRE 2960 CNRS Université Paul Sabatier Toulouse III, 37, allées Jules Guesde 31073 Toulouse Cedex, France
Clotilde Coudray Centre d'Anthropologie, FRE 2960 CNRS Université Paul Sabatier Toulouse III, 37, allées Jules Guesde 31073 Toulouse Cedex, France
A. Silvana Santachiara-Benerecetti Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Ornella Semino Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Hans-Jürgen Bandelt Department of Mathematics University of Hamburg, Bundesstrasse 55 20146 Hamburg, Germany
Antonio Torroni* Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
*To whom correspondence should be addressed. E-mail: torroni@ipvgen.unipv.it
References
1. H.-J. Bandelt, V. Macaulay, M. Richards, in Examining the Farming/Language Dispersal Hypothesis, P. Bellwood, C. Renfrew, Eds. (McDonald Institute Monographs, McDonald Institute for Archaeological Research, Cambridge, 2003), pp. 99-111. 2. M. Richards, Annu. Rev. Anthropol. 32, 135 (2003). 3. P. Bellwood, Science 306, 1681 (2004). 4. C. Ehret, S. O. Y. Keita, P. Newman, Science 306, 1680 (2004). 5. D. W. Phillipson, African Archaeology (Cambridge Univ. Press, Cambridge, ed. 3, 2005). 6. C. Ehret, A Reconstruction of Proto-Afroasiatic (Proto-Afrasian): Vowels, Tone, Consonants and Vocabulary (Univ. of California Press, Berkeley/Los Angeles/London, 1995). 7. M. Brett, E. Fentress, The Berbers: the Peoples of Africa (Blackwell, Oxford, 1996). 8. J. C. Rando et al., Ann. Hum. Genet. 62, 531 (1998). 9. V. Macaulay et al., Am. J. Hum. Genet. 64, 232 (1999). 10. R. Kuper, S. Kröpelin, Science 313, 803 (2006).
Posts: 2198 | Registered: Jun 2006
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Both M1 and U6 derivatives in southwest Asia are downstream derivatives of those based in east Africa [for M1] and North Africa [for U6] respectively. As for linguistics, the only branch outside of Africa, is the Semitic branch as the 'youngest' of all the branches, aside from the intra-African development of the "Berber" groups, as another yet young branch of Afrasan.
The predominant lineages in North Africa again, from a paternal side, is predominantly African, with the PN2 transition derivatives. The Northwest Africans have very little Upper Paleolithic contribution in their gene pool.
-------------------- Truth - a liar penetrating device! Posts: 5964 | Registered: Jan 2005
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Afterall, the article was taken from Science Magazine, one of two prestigious science journals. The other journal is of cource, nature.
If you could response, similar to the article, with references and notes, that would be nice.
Cheers!
Supercar does not need say anything except BS. And I agree with him.
The argument fails mainly because of the fact that the Afro-Asiatic languages have their ultimate origin in Africa rather Europe. Secondly, the idea of M1 back migrating into Africa during this period is ludicris on two counts. First, around 40,000 BC Europe was occupied mainly by Neanderthals. They begin to be replaced in Europe around 30,000 by the CroMagnon people at Les Eyzies. The CroMagnon people carry the N haplogroup.
Secondly, the archaeological evidence make it clear that the CroMagnon people probably originated in Africa and spread east from Iberia into the Levant. Since the migration of the first homo sapien sapiens was from West to East there was no way M1 could have back migrated into Africa, carried by speakers of AfroAsiatic languages since the Natufians who settled the Levant did not come on the scene for another 10,000+ years.
Moreover, M1 is decendant from the L lineages the same as N. If N and M1 are descendant from L how could M1 have originated in Europe when the CroMagnon carrying N haplogroup were the dominant group in the area.
Most people forget that the Neanderthals were not replaced in the Levant, until long after CroMagnon man had already settled much of Western Europe. This is just another ploy to explain the appearence of modern Europeans in Europe before the Indo Europeans arrive in the area only 5000- 4000 ybp.
Perhaps he should add that you should go back and read his post and respond to his 4 substantive points:
- Both M1 and U6 derivatives in southwest Asia are downstream derivatives of those based in east Africa [for M1] and North Africa [for U6] respectively.
- As for linguistics, the only branch outside of Africa, is the Semitic branch as the 'youngest' of all the branches, aside from the intra-African development of the "Berber" groups, as another yet young branch of Afrasan.
- The predominant lineages in North Africa again, from a paternal side, is predominantly African, with the PN2 transition derivatives.
- The Northwest Africans have very little Upper Paleolithic contribution in their gene pool.
^ Supercar actually provided more substance than both you and the article you posted combined.
You responded with a 'quip' but addressed no point of substance.
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posted
^The only back-migration to North Africa I am aware of is represented through the European maternal lineages found among the coastal white Berbers and of course what little Arab paternal lineages are found from the Arab invasion.
Other than that, the lineages of North African people are preponderantly indigenous.
Why do you suddenly attack Supe's past responses as "BS", Arwa? Is there something not to your liking?
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Djehuti: ^The only back-migration to North Africa I am aware of is represented through the European maternal lineages found among the coastal white Berbers and of course what little Arab paternal lineages are found from the Arab invasion.
Other than that, the lineages of North African people are preponderantly indigenous.
In that case then most modern Egyptians haven't changed much from the ancients, since you say there haven't been any significant back migration and only little arab lineages among Egyptians and they are "preponderantly indigenous", right?
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posted
^If you were paying attention, I was referring to North Africa as a whole. Arab lineages follow a gradient that decreases from east to west and the converse is true. Since Egypt specifically is the main entry point for most of the Arab invasion, it is not surprising that Egypt has the largest percentage of Arab lineages in North Africa but even then African lineages are still largely present. Also,we must not forget other foreign lineages that have filtered into Egypt since before the Arabs like other Asiatics and even Europeans. That said, of course there was a significant change in the population of Egypt:
^Notice the percentage of African E lineages sampled from 'Arab' Egyptians alone.
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: ^If you were paying attention, I was referring to North Africa as a whole. Arab lineages follow a gradient that decreases from east to west and the converse is true. Since Egypt specifically is the main entry point for most of the Arab invasion, it is not surprising that Egypt has the largest percentage of Arab lineages in North Africa but even then African lineages are still largely present. Also,we must not forget other foreign lineages that have filtered into Egypt since before the Arabs like other Asiatics and even Europeans. That said, of course there was a significant change in the population of Egypt:
^Notice the percentage of African E lineages sampled from 'Arab' Egyptians alone.
posted
Linguistical BS also. They resort to the use of North Africa and Western Asia to confuse and hide the fact that M1 in Ethiopia/Arabia (Saudi/Yemeni) share the same roots! The Horn of Africa was once contiguous landmass and not a bridge per present geographic delineation.
Commentary/response: They said "This would entail a Near Eastern origin of the Afro-Asiatic language" but this is a red herring? It is the other way around where Afro-Asiatic origin created the Near Easter language/culture pool and subsequent differentiation due to the birth of the "Fertile Crescent" (Middle East?)
POINT: They say "As we proposed in our Report, the arrival of M1 in Africa is most likely contemporary with that of U6" which is odd because Africa is the origin of both M1 and U5/U6. Why the trap of designating North Africa as a different land mass when it is contiguous with the continent! The Atlas Mountains are a perfect place (dietary/climate) where M1 and U5/6 differentiated from the south and with that differentiation it developed over time with migrations (at least 600 AD-could be earlier). I arbitrarily used 600 A.D. because Tariq was invited to Spain by the Goths and various source state the Germanic tribes were familiar with Berbers (Amazigh?).
Posts: 1290 | From: usa | Registered: May 2005
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quote:Djehuti: ^The only back-migration to North Africa I am aware of is represented through the European maternal lineages found among the coastal white Berbers and of course what little Arab paternal lineages are found from the Arab invasion.
Other than that, the lineages of North African people are preponderantly indigenous.
In that case then most modern Egyptians haven't changed much from the ancients, since you say there haven't been any significant back migration and only little arab lineages among Egyptians and they are "preponderantly indigenous", right?
The Syrian, Greek, Roman and Arab invasion of Egypt is not considered back migration in the anthropological sense, for the same reasons that the Dutch/Boer and British invasions of the Southern Africa are not considered back migration.
These things are called - imperialism.
Posts: 15202 | Registered: Jun 2004
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quote:Originally posted by Clyde Winters: Where was this chart published?
Here (The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations)
quote:Originally posted by Bettyboo: You people believe in too much science. Neanderthals never existed.
What you fail to understand is that unlike religion, science is a matter of fact or strong claims backed up by evidence.
If you believe Neanderthals never existed, then go tell that to the scientist who study their skeletal remains! LMAOPosts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
I believe the article in Science magazine is primarily touching upon Maghrebian[north-west] Africa as opposed to Egypt. The article erroneously states that phenotypically most northern Africans are distinct from sub-saharan Africans without defining a definitive phenotype for sub-Sahara. The article further tries to group northern Africans with Europeans and the Middle East despite the latter area being very diverse and hetrogenous itself. The problem with the following is most northern Africans looking nothing like Europeans and your typical Middle Eastern would never be Erupoid just based on skin color and apperance. I also gurantee you that most northern African/Middle Easteners genetic profile is just as different from a sub-Saharan as to a northern and most southern Europeans.[except areas where interaction between thw two areas are present].
As far as contemporary Egypt, people overemphasize the invasions instead of migrations that occured in pharoanic and post-pharoanic eras. Most of the people who invaded Egypt never really intermingled with the local people except for groups that came in with the said invaders.
Posts: 8675 | From: Tukuler al~Takruri as Ardo since OCT2014 | Registered: Feb 2003
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quote:Originally posted by ausar: I believe the article in Science magazine is primarily touching upon Maghrebian[north-west] Africa as opposed to Egypt. The article erroneously states that phenotypically most northern Africans are distinct from sub-saharan Africans without defining a definitive phenotype for sub-Sahara. The article further tries to group northern Africans with Europeans and the Middle East despite the latter area being very diverse and hetrogenous itself. The problem with the following is most northern Africans looking nothing like Europeans and your typical Middle Eastern would never be Erupoid just based on skin color and apperance. I also gurantee you that most northern African/Middle Easteners genetic profile is just as different from a sub-Saharan as to a northern and most southern Europeans.[except areas where interaction between thw two areas are present].
You are correct as usual, Ausar.
quote:As far as contemporary Egypt, people overemphasize the invasions instead of migrations that occured in pharoanic and post-pharoanic eras. Most of the people who invaded Egypt never really intermingled with the local people except for groups that came in with the said invaders.
Hence the Bedouin tribes who intermarried with the locals and not the elite themselves.
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
Taking into account the sharing of genes between Southern Europe and North Africa, it would only be natural for the sea route to reflect the migratory pattern, i.e invasion/colonization from Gebraltar to Spain to 700 years of Arab/Berber control, i.e. migratory pattern South to North! For the Arabs to get to North Africa, the movement is West to East>>North to Spain so it is feasible for the bi-rectional flow with conquest and subsequuent dynastic defeat of the various groups (Ayubid, Almohad, etc) and I am sure many who became acclimated choose Christianity or went further North, or depending on societal position returned to diferent countries of origin closer to dynastic origin. It was said there were quite a few Syrians and Slavs who occupied positions of influence and when their respective dynasty fell, instead of going back, they probably went to Morocco, Mali, Algeria, etc to be close to their place of birth, which happened to be Spain!
Posts: 1290 | From: usa | Registered: May 2005
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posted
With four points and an B.S. can't take you to Science Magazine or nature--let alone any journals.
quote:Originally posted by rasol:
quote:Originally posted by Arwa: Supercar,
Do you have anything to add than an B.S.?
Perhaps he should add that you should go back and read his post and respond to his 4 substantive points:
- Both M1 and U6 derivatives in southwest Asia are downstream derivatives of those based in east Africa [for M1] and North Africa [for U6] respectively.
- As for linguistics, the only branch outside of Africa, is the Semitic branch as the 'youngest' of all the branches, aside from the intra-African development of the "Berber" groups, as another yet young branch of Afrasan.
- The predominant lineages in North Africa again, from a paternal side, is predominantly African, with the PN2 transition derivatives.
- The Northwest Africans have very little Upper Paleolithic contribution in their gene pool.
^ Supercar actually provided more substance than both you and the article you posted combined.
You responded with a 'quip' but addressed no point of substance.
This page shows a good example of Egyptian phenotypical variety. Like Ausar said, even though there are some who are descended from foreign invaders over the years, there is still a lot of the indigenous black to light brown population to be seen. The question being which phenotypical traits are more representative of ancient populations versus the modern one.
Science 6 April 2007: Vol. 316. no. 5821, pp. 50 - 53 Letters
Timing of a Back-Migration into Africa
Indigenous North Africans are genetically quite distinct from sub-Saharan Africans (1), and this difference is reflected in their lighter skin and European/Middle Eastern physical features. We have previously suggested, on the basis of the distribution of mtDNA type M1, that North Africans are largely descended from a back-migration into Africa within the last 2000 to 15,000 years, resettling the temporarily lush Sahara and spreading the Afro-Asiatic language family (2). In their Report "The mtDNA legacy of the Levantine early Upper Palaeolithic in Africa" (15 Dec. 2006, p. 1767), A. Olivieri and colleagues used high-resolution mtDNA data to propose that the migration from Asia back to North Africa happened much earlier, and they link the settlement of North Africa with the settlement of Europe 40,000 to 45,000 years ago.
Three points lead us to believe that our younger chronology for the back-migration into northern Africa still merits consideration. First, the mtDNA trees reconstructed by Olivieri and colleagues are less than conclusive because they consist of phylogeographically mixed branches, which cause uncertainty in identifying the relevant founder nodes for genetic dating. Second, in our view the fact that the North African mtDNA marker types still correspond so closely with the Afro-Asiatic language zone argues against the existence of that correlation for tens of thousands of years. Third, cave art in the Sahara shows that in Neolithic times (around 5000 B.C.), the population of the Sahara was still of sub-Saharan African ancestry (see figure), whereas "Europoid" figures documenting the arrival of west Eurasians appear later in the cave art record (3).
Within the framework of our younger chronology, the occurrence of low frequencies of M1 types in the European Mediterranean can be explained by diffusion from the Middle East and North Africa during and since the Neolithic. The Sardinian M1 mtDNA founder date of 7700 ± 3100 years years calculated by Olivieri and colleagues would conveniently fit with the arrival of farming in the European Mediterranean.
In conclusion, we suggest that more recent influx from Asia, possibly since the Last Glacial Maximum 20,000 years ago, may better explain some of the major genetic and linguistic patterns in North Africa and adjacent areas [cf. (4, 5)]. We nevertheless believe that future archaeogenetic research on Ice Age Africa and subsequent periods will benefit greatly from the complete mtDNA sequencing approach taken by Olivieri and colleagues.
Peter Forster* Department of Forensic Science and Chemistry Anglia Ruskin University, Cambridge CB1 1PT, UK and New Hall, University of Cambridge Cambridge CB3 0DF, UK
*To whom correspondence should be addressed. E-mail: pf223@cam.ac.uk
Valentino Romano Dipartimento di Oncologia Sperimentale e Applicazioni Cliniche Università di Palermo Palermo, Italy and Associazione OASI Maria SS. (I.R.C.C.S.) Troina, Italy
References
1. L.-L. Cavalli-Sforza, P. Menozzi, A. Piazza, The History and Geography of Human Genes (Princeton Univ. Press, Princeton, NJ, 1994). 2. P. Forster, Philos. Trans. R. Soc. London Ser. B 39, 255 (2004). 3. A. Muzzolini, L'Art Rupestre Prehistorique des Massifs Centraux Sahariens (BAR, Oxford, 1986). 4. C. Renfrew, Cambr. Archaeol. J. 1, 3 (1991). 5. I. Diakonoff, J. Semit. Stud. 43, 209 (1998).
Evergreen Writes:
First and foremost, we should all be thankful that these scholars came out into the light with their opinions on this matter. North American scholars are much more subtle and subversive with such views. This gives us a great opportunity to impact the public discourse. I encourage each of you to email these scholars and the journal Science to make an impact. I will….
{Indigenous North Africans are genetically quite distinct from sub-Saharan Africans}
Evergreen Writes:
It is of interest that Forster uses a non-peer reviewed, 1994 source to support this claim. The fact is indigenous North Africans are not homogenous. More recent studies show heterogeneity across North Africa, even at the micro-geographic level.
Evergreen Posts:
Female gene pools of Berber and Arab neighboring communities in central Tunisia: microstructure of mtDNA variation in North Africa
Human Biology 2005 Feb;77(1):61-70
North African populations are considered genetically closer to Eurasians than to sub-Saharans. However, they display a considerably high mtDNA heterogeneity among them, namely in the frequencies of the U6, East African, and sub-Saharan haplogroups. In this study, we describe and compare the female gene pools of two neighboring Tunisian populations, Kesra (Berber) and Zriba (non-Berber), which have contrasting historical backgrounds. Both populations presented lower diversity values than those observed for other North African populations, and they were the only populations not showing significant negative Fu's F(S) values. Kesra displayed a much higher proportion of typical sub-Saharan haplotypes (49%, including 4.2% of M1 haplogroup) than Zriba (8%). With respect to U6 sequences, frequencies were low (2% in Kesra and 8% in Zriba), and all belonged to the subhaplogroup U6a. An analysis of these data in the context of North Africa reveals that the emerging picture is complex, because Zriba would match the profile of a Berber Moroccan population, whereas Kesra, which shows twice the frequency of sub-Saharan lineages normally observed in northern coastal populations, would match a western Saharan population except for the low U6 frequency. The North African patchy mtDNA landscape has no parallel in other regions of the world and increasing the number of sampled populations has not been accompanied by any substantial increase in our understanding of its phylogeography. Available data up to now rely on sampling small, scattered populations, although they are carefully characterized in terms of their ethnic, linguistic, and historical backgrounds. It is therefore doubtful that this picture truly represents the complex historical demography of the region rather than being just the result of the type of samplings performed so far.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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The principal problem with great syntheses of languages, genes, and figurines (or pots) is that they lump together different migrational and cultural processes and especially overstretch recent events of the Holocene, thereby downplaying or swamping the genetic signals that point to much earlier events of the Pleistocene (1, 2).
Forster and Romano propose a recent arrival--within the last 2000 to 15,000 years--of haplogroup M1 in North Africa from western Asia, linked to the spread of Afro-Asiatic languages. This would entail a Near Eastern origin of the Afro-Asiatic language family and thus would be in agreement with Bellwood (3), provided that one subscribes to such a tight link between genes and languages. Afro-Asiatic scholarship (4), as well as the coalescence times of both M1a and M1b and the diverse basal distribution of M1a lineages especially in East Africa, however, militate against this interpretation. As we proposed in our Report, the arrival of M1 in Africa is most likely contemporary with that of U6, but if one alternatively hypothesized that only M1a originally went into the Northeast African Mediterranean coast, then 25,000 to 30,000 years ago would be the realistic time frame.
The latter hypothesis is valid when one assumes the less parsimonious scenario that only haplogroup U6 was involved 40,000 to 45,000 years ago in the early Upper Palaeolithic diffusion of Levantine populations into North Africa and that a diffusion of M1a lineages marked a new phase in the Nile Valley Complex, 25,000 to 30,000 years ago (5). It is then also more plausible to see the development and emergence of proto-Afro-Asiatic languages there, in the Nile Valley (6, 7). Later migrations and gene flow, which undoubtedly took place, have certainly complicated phylogeographic patterns. For instance, one may also envision some mutual contacts between the Levantine Natufian culture and contemporary autochthonous cultures of the Lower Nile Valley (~15,000 years ago). Later Neolithic influence then brought a whole package of Near Eastern mtDNA lineages into all of North Africa, as attested, for instance, by the relatively high frequency of mtDNA haplogroups H, J, and T in modern North African populations (8, 9).
The cave art argument adduced by Forster and Romano has no impact on the issue of the late Near Eastern influx because haplogroup U6 very clearly testifies to an early presence in North Africa of Near Eastern lineages, which must have proceeded to as far as Northwest Africa with the ancestors of the Iberomaurusians before the Late Glacial Maximum (8). The anthropological evidence from North Africa, pointing to the autochthonous Mechta-Afalou physical type, with continuity well into the Capsian of the mid-Holocene, gives clear support to the ancient presence of Upper Palaeolithic people in North Africa (5). Moreover, the presence of figurines of sub-Saharan type in the cave art of the Sahara may simply be indicative of resettlement of the region by groups from the south, already adapted to savannah ecology, after the early Holocene arrival of monsoon rains changed the Sahara into a habitable region (10). Thus, the argument is not informative on the antiquity of a "Europoid" settlement in North Africa.
Anna Olivieri Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Alessandro Achilli Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Maria Pala Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Vincenza Battaglia Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Simona Fornarino Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Nadia Al-Zahery Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Department of Biotechnology College of Science University of Baghdad, Iraq
Rosaria Scozzari Dipartimento di Genetica e Biologia Molecolare Università "La Sapienza," Piazzale Aldo Moro 5 00185 Rome, Italy
Fulvio Cruciani Dipartimento di Genetica e Biologia Molecolare Università "La Sapienza," Piazzale Aldo Moro 5 00185 Rome, Italy
Doron M. Behar Molecular Medicine Laboratory Rambam Health Care Campus Efron 9 street, Bat Galim 31096 Haifa, Israel
Jean-Michel Dugoujon Centre d'Anthropologie, FRE 2960 CNRS Université Paul Sabatier Toulouse III, 37, allées Jules Guesde 31073 Toulouse Cedex, France
Clotilde Coudray Centre d'Anthropologie, FRE 2960 CNRS Université Paul Sabatier Toulouse III, 37, allées Jules Guesde 31073 Toulouse Cedex, France
A. Silvana Santachiara-Benerecetti Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Ornella Semino Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
Hans-Jürgen Bandelt Department of Mathematics University of Hamburg, Bundesstrasse 55 20146 Hamburg, Germany
Antonio Torroni* Dipartimento di Genetica e Microbiologia Università di Pavia, Via Ferrata 1 27100 Pavia, Italy
*To whom correspondence should be addressed. E-mail: torroni@ipvgen.unipv.it
References
1. H.-J. Bandelt, V. Macaulay, M. Richards, in Examining the Farming/Language Dispersal Hypothesis, P. Bellwood, C. Renfrew, Eds. (McDonald Institute Monographs, McDonald Institute for Archaeological Research, Cambridge, 2003), pp. 99-111. 2. M. Richards, Annu. Rev. Anthropol. 32, 135 (2003). 3. P. Bellwood, Science 306, 1681 (2004). 4. C. Ehret, S. O. Y. Keita, P. Newman, Science 306, 1680 (2004). 5. D. W. Phillipson, African Archaeology (Cambridge Univ. Press, Cambridge, ed. 3, 2005). 6. C. Ehret, A Reconstruction of Proto-Afroasiatic (Proto-Afrasian): Vowels, Tone, Consonants and Vocabulary (Univ. of California Press, Berkeley/Los Angeles/London, 1995). 7. M. Brett, E. Fentress, The Berbers: the Peoples of Africa (Blackwell, Oxford, 1996). 8. J. C. Rando et al., Ann. Hum. Genet. 62, 531 (1998). 9. V. Macaulay et al., Am. J. Hum. Genet. 64, 232 (1999). 10. R. Kuper, S. Kröpelin, Science 313, 803 (2006).
{The latter hypothesis is valid when one assumes the less parsimonious scenario that only haplogroup U6 was involved 40,000 to 45,000 years ago in the early Upper Palaeolithic diffusion of Levantine populations into North Africa and that a diffusion of M1a lineages marked a new phase in the Nile Valley Complex, 25,000 to 30,000 years ago (5).}
Evergreen Writes:
When the Olivieri study initially came out I emphasized the fact that this study was based in part on archaeological inputs. This subtlety alluded some. This issue has resurfaced. Did the UP Nile Valley archaeological complex derive from Africa or Asia?
{The cave art argument adduced by Forster and Romano has no impact on the issue of the late Near Eastern influx because haplogroup U6 very clearly testifies to an early presence in North Africa of Near Eastern lineages, which must have proceeded to as far as Northwest Africa with the ancestors of the Iberomaurusians before the Late Glacial Maximum (8).}
Evergreen Writes:
Yet, more recent studies indicate that ALL human populations had phenotypic affinities with modern Sub-Saharan Africans until very recently.
Evergreen Posts:
Genetic evidence for the convergent evolution of light skin in europeans and East asians. Mol Biol Evol. 2007 Mar;24(3):710-22. Epub 2006 Dec 20.
Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical F(ST) approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians.
{The anthropological evidence from North Africa, pointing to the autochthonous Mechta-Afalou physical type, with continuity well into the Capsian of the mid-Holocene, gives clear support to the ancient presence of Upper Palaeolithic people in North Africa (5). …….Thus, the argument is not informative on the antiquity of a "Europoid" settlement in North Africa.}
Evergreen Writes:
“Europoid” ….WTF? This helps us contextualize Cruciani.
Evergreen Posts:
COLIN P. GROVES AND ALAN THORNE 1999 The Terminal Pleistocene and Early Holocene Populations of Northern Africa. Homo 50(3):249-262. ISSN 0018-442X. Abstract:
We studied three northern African samples of human cranial remains from the Pleistocene/Holocene boundary: Afalou-bou-Rhummel, Taforalt, and Sudanese Nubia (Jebel Sahaba and Tushka), and compared them to late Pleistocene Europeans and Africans. Despite their relatively late dates, all three of our own samples exhibit the robusticity typical of late Pleistocene Homo sapiens. As far as population affinities are concerned, Taforalt is Caucasoid and closely resembles late Pleistocene Europeans, Sudanese Nubia is Negroid, and Afalou exhibits an intermediate status. Evidently the Caucasoid/Negroid transition has fluctuated north and south over time, perhaps following the changes in the distribution of climatic zones. Evergreen Writes:
Note that in the Groves/Thorne study the so-called Afalou ‘intermediate’ type is most similar to the modern Dogon!
Posts: 2007 | From: Washington State | Registered: Oct 2006
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{The anthropological evidence from North Africa, pointing to the autochthonous Mechta-Afalou physical type, with continuity well into the Capsian of the mid-Holocene, gives clear support to the ancient presence of Upper Palaeolithic people in North Africa (5). …….Thus, the argument is not informative on the antiquity of a "Europoid" settlement in North Africa.}
Evergreen Writes:
“Europoid” ….WTF? This helps us contextualize Cruciani.
Evergreen Posts:
COLIN P. GROVES AND ALAN THORNE 1999 The Terminal Pleistocene and Early Holocene Populations of Northern Africa. Homo 50(3):249-262. ISSN 0018-442X. Abstract:
We studied three northern African samples of human cranial remains from the Pleistocene/Holocene boundary: Afalou-bou-Rhummel, Taforalt, and Sudanese Nubia (Jebel Sahaba and Tushka), and compared them to late Pleistocene Europeans and Africans. Despite their relatively late dates, all three of our own samples exhibit the robusticity typical of late Pleistocene Homo sapiens. As far as population affinities are concerned, Taforalt is Caucasoid and closely resembles late Pleistocene Europeans, Sudanese Nubia is Negroid, and Afalou exhibits an intermediate status. Evidently the Caucasoid/Negroid transition has fluctuated north and south over time, perhaps following the changes in the distribution of climatic zones. Evergreen Writes:
Note that in the Groves/Thorne study the so-called Afalou ‘intermediate’ type is most similar to the modern Dogon!
posted
So I ask, where are Arwa's answers to the above discrepancies as pointed out by Evergreen?
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
Arwa, the issue here is that populations 30,000 - 40,000 years ago were not CAUCASIAN in any sense of the term. To claim that the populations 40,000 years ago are the same as the present appearance of populations in ANY area of the world is absolutely ridiculous. The only populations that can claim such a link are those who were relatively isolated from other patterns of migrations SINCE 40,000 years ago. And those populations that have such isolated histories are ALL BLACK. The people of the Andaman Islands are one example and the Aborigines of Tasmania and Australia are another example. Therefore to suggest in any way that those 40,000 year old asian migrants looked like the modern pale skinned populations along the coast of North Africa is nonsense.
Second, we KNOW that there was a recent historical migration of populations from Europe and Asia into North AFrica over the last 4,000 years and that this is more relevant to the study of modern dispersions of pale skinned populations than studies of populations 40,000 years ago. We know that the Sea Peoples invaded Libya and were among the first documented examples of white populations in North Africa. We know about the Greeks and Romans. We know about the arrival of the Muslims, all of which have had a significant impact on the coastal North African zone. Prior to that the populations, as documented in the rock art and elsewhere, was purely indigenous black African.
To put this in context, 40,000 years ago humans had only been in Europe for 5,000 years or so. They had not developed the distinct traits that would define what we call modern European traits of white skin and features. The populations of Europe 40,000 years ago were as different from modern Europeans as the Aborigines of Australia are different from white Australians. Therefore, to suggest that these populations in North Africa brought a white founder gene to North Africa, when there was no predominant white complexion among human populations 40,000 years ago, is the reason for the absurdity of this article.
Posts: 8895 | Registered: May 2005
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quote:Originally posted by Doug M: Arwa, the issue here is that populations 30,000 - 40,000 years ago were not CAUCASIAN in any sense of the term. To claim that the populations 40,000 years ago are the same as the present appearance of populations in ANY area of the world is absolutely ridiculous. The only populations that can claim such a link are those who were relatively isolated from other patterns of migrations SINCE 40,000 years ago. And those populations that have such isolated histories are ALL BLACK. The people of the Andaman Islands are one example and the Aborigines of Tasmania and Australia are another example. Therefore to suggest in any way that those 40,000 year old asian migrants looked like the modern pale skinned populations along the coast of North Africa is nonsense.
Second, we KNOW that there was a recent historical migration of populations from Europe and Asia into North AFrica over the last 4,000 years and that this is more relevant to the study of modern dispersions of pale skinned populations than studies of populations 40,000 years ago. We know that the Sea Peoples invaded Libya and were among the first documented examples of white populations in North Africa. We know about the Greeks and Romans. We know about the arrival of the Muslims, all of which have had a significant impact on the coastal North African zone. Prior to that the populations, as documented in the rock art and elsewhere, was purely indigenous black African.
To put this in context, 40,000 years ago humans had only been in Europe for 5,000 years or so. They had not developed the distinct traits that would define what we call modern European traits of white skin and features. The populations of Europe 40,000 years ago were as different from modern Europeans as the Aborigines of Australia are different from white Australians. Therefore, to suggest that these populations in North Africa brought a white founder gene to North Africa, when there was no predominant white complexion among human populations 40,000 years ago, is the reason for the absurdity of this article.
Ok Doug I need some help understanding somethings. When did humans become "non-black" if not 40,000 years ago? Are you sure there were no "non-black" anywhere on the Earth 40,000 years ago and if so can you give me some documentation.
The reason I asked is because you don't seem as emotional as the others when it comes to race questions and that I was told that the R1b haplotype in Cameroon was a "black" haplotype that went back 30,000 years and wasn't a semetic/Western Asian/Arab haplotype. Can you tell me why it isn't..despite the appearance of Cameroon people?
At what point in time approximately did people become non-black and how can we or science tell the difference?
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quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]..... I need some help understanding somethings. When did humans become "non-black" if not 40,000 years ago?
Evergreen Writes:
Great question.
quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]....and that I was told that the R1b haplotype in Cameroon was a "black" haplotype that went back 30,000 years
Evergreen Writes:
It is R1* not R1b that is found in West Africa.
quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]At what point in time approximately did people become non-black and how can we or science tell the difference?
Evergreen Writes:
The study below is a good starting point.
Genetic evidence for the convergent evolution of light skin in europeans and East asians. Mol Biol Evol. 2007 Mar;24(3):710-22. Epub 2006 Dec 20
Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical F(ST) approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]..... I need some help understanding somethings. When did humans become "non-black" if not 40,000 years ago?
Evergreen Writes:
Great question.
quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]....and that I was told that the R1b haplotype in Cameroon was a "black" haplotype that went back 30,000 years
Evergreen Writes:
It is R1* not R1b that is found in West Africa.
quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]At what point in time approximately did people become non-black and how can we or science tell the difference?
Evergreen Writes:
The study below is a good starting point.
Genetic evidence for the convergent evolution of light skin in europeans and East asians. Mol Biol Evol. 2007 Mar;24(3):710-22. Epub 2006 Dec 20
Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical F(ST) approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians.
Thanks for the post but does it have dates? What does "recent" mean and what about the other factors involved like body plans/types etc. that are non tropical? I need an approximation during this Ice Age that did all these changes because I am lost here with the dating of Haplo clusters and how to determine if something is "definetly" black like the R1 in Cameroon.
Posts: 336 | Registered: Apr 2007
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quote:Originally posted by Nice Vidadavida *sigh*: [QUOTE]Thanks for the post but does it have dates? What does "recent" mean
Evergreen Writes:
Again, good question. Not sure that this has been resolved to that level. We do know that it posts dates the seperation of Europeans from Asians. Europeans are distinguished by the down-stream European-specific lineage R1b. Hence, this differentiation would post-date 35kya. Also as we know the remains in the Nile Valley corridor during the period in question all have affinities with recent Sub-Saharan Africans as do the earliest Europeans (i.e., Grimaldi Man). In addition, there is a postive correlation between melanin level and limb attenuation (see Brace et al.). Mesolithic Europeans had somewhat tropical limb ratios.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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It means *after* East Asians and Europeans split, which means no earlier then 30kya~ and based upon the mcra of European depigmentation mutations as recent as 12kya~.
quote: and what about the other factors involved like body plans/types etc. that are non tropi cal? I need an approximation during this Ice Age that did all these changes because I am lost here with the dating of Haplo clusters and how to determine if something is "definetly" black like the R1 in Cameroon.
All known skeletal material of central Africa shows tropical adaptation.
There is no evidence of any white population ever living in Cameroon.
Moreover there are no white people with R1 haplotype either.....the earliest Europeans having had R1b, having already split from R1a Asians, and still were not white.
In turn both of these lineages had split prior from R1.
Posts: 15202 | Registered: Jun 2004
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posted
The problem with all these claims in back-migrations to ancient or prehistoric Africa, is that there seems to be confusion with actual pattern of genetic signitures.
Thus people get North African U6 mixed up with European U, and East African M1 with Indian M.
As pointed out above, it is similar to West African R* associated with European R1.
It is likely either the result of common origins or parallel mutations-- perhaps both.
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
LMao arguing that populations 40,000 years ago were "Black". We do not know that they were dark skinned. Broad featured, sure. Last I checked that wasn't a color. Neanderthals were broad featured as well. Does that make them Black? In fact all populations of the world began with broader features and more robustness of cranial features.
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quote:Originally posted by maa'-kherew: LMao arguing that populations 40,000 years ago were "Black". We do not know that they were dark skinned. Broad featured, sure. Last I checked that wasn't a color. Neanderthals were broad featured as well. Does that make them Black? In fact all populations of the world began with broader features and more robustness of cranial features.
Evergreen Writes:
It is less relevent how we label these populations. The fact of the matter is peer-reveiewed assessment has determined that EMH had melanin levels and phenetic characteristics that show affinity with modern SSA. In a social context these people would be called Blacks.
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posted
Mitochondrial DNA transit between West Asia and North Africa inferred from U6 phylogeography Nicole Maca-Meyer,1 Ana M González,1 José Pestano,2 Carlos Flores,1 José M Larruga,1 and Vicente M Cabreracorresponding author1 1Departamento de Genética, Facultad de Biología, Universidad de La Laguna, Tenerife, SPAIN 2Laboratorio de Genética, Facultad de Medicina, Universidad de Las Palmas de Gran Canaria, Gran Canaria, SPAIN corresponding authorCorresponding author. Nicole Maca-Meyer: nmacame@ull.es; Ana M González: amglez@ull.es; José Pestano: jpestano@dbbf.ulpgc.es; Carlos Flores: cflores@ull.es; José M Larruga: jlarruga@ull.es; Vicente M Cabrera: vcabrera@ull.es
Abstract
Background World-wide phylogeographic distribution of human complete mitochondrial DNA sequences suggested a West Asian origin for the autochthonous North African lineage U6. We report here a more detailed analysis of this lineage, unraveling successive expansions that affected not only Africa but neighboring regions such as the Near East, the Iberian Peninsula and the Canary Islands.
Results Divergence times, geographic origin and expansions of the U6 mitochondrial DNA clade, have been deduced from the analysis of 14 complete U6 sequences, and 56 different haplotypes, characterized by hypervariable segment sequences and RFLPs.
Conclusions The most probable origin of the proto-U6 lineage was the Near East. Around 30,000 years ago it spread to North Africa where it represents a signature of regional continuity. Subgroup U6a reflects the first African expansion from the Maghrib returning to the east in Paleolithic times. Derivative clade U6a1 signals a posterior movement from East Africa back to the Maghrib and the Near East. This migration coincides with the probable Afroasiatic linguistic expansion. U6b and U6c clades, restricted to West Africa, had more localized expansions. U6b probably reached the Iberian Peninsula during the Capsian diffusion in North Africa. Two autochthonous derivatives of these clades (U6b1 and U6c1) indicate the arrival of North African settlers to the Canarian Archipelago in prehistoric times, most probably due to the Saharan desiccation. The absence of these Canarian lineages nowadays in Africa suggests important demographic movements in the western area of this Continent. Top Abstract >Background Results Discussion Methods Supplementary material References
Background
Attested presence of Caucasian people in Northern Africa goes up to Paleolithic times. From the archaeological record it has been proposed that, as early as 45,000 years ago (ya), anatomically modern humans, most probably expanded the Aterian stone industry from the Maghrib into most of the Sahara [1]. More evolved skeletal remains indicate that 20,000 years later the Iberomaurusian makers, replaced the Aterian culture in the coastal Maghrib. Several hypothesis have been forwarded concerning the Iberomaurusian origin. They can be resumed in those which propose an arrival, from the East, either from the Near East or Eastern Africa, and those which point to west Mediterranean Europe, either from the Iberian Peninsula, across the Gibraltar Strait, or from Italy, via Sicily, as their most probable homeland [2]. Between 10,000 and 6,000 ya the Neolithic Capsian industry flourished farther inland. The historic penetration in the area of classical Mediterranean cultures, ending with the Islamic domination, supposed a strong cultural influx. However, it seems that the demic impact was not strong enough to modify the prehistoric genetic pool.
Linguistic research suggests that the Afroasiatic phylum of languages could have originated and extended with these Caucasians, either from the Near East or Eastern Africa and that posterior developments of the Capsian Neolithic in the Maghrib might be related to the origin and dispersal of proto-Berber speaking people into the area [3]. Nowadays, the Berber speakers, scattered throughout Northwest Africa from the Atlantic to the Lybic desert and from the Mediterranean shores to the south of the Sahel, are considered the genuine descendants of those prehistoric colonizers. Some important issues are pending of resolution to clarify the past and present of the North African Caucasians: To which extent the Neolithic waves substituted the Paleolithic recipients? Which is the most probable origin of these prehistoric occupants? Did they come from Europe, East Africa, Southwest Asia or are they a result of an "in situ" evolution? Is there a correspondence between the Afroasiatic diversification and the spread of Caucasians?
Recently, molecular genetic research on North African populations has contributed new data to test the major issues proposed on archaeological, anthropological and linguistic grounds. The studies based on uniparental genetic markers have been particularly informative. Both, mitochondrial DNA (mtDNA) sequences [4,5], and Y-chromosome binary markers [6,7] detected specific North African haplotypes that confirm an ancient human colonization for this area and a sharp discontinuity between Northwest Africa and the Iberian Peninsula. From a mtDNA point of view, the most informative of these genetic markers is the North African clade U6. On the basis of complete mtDNA sequences, it has been proposed that U6 lineages, mainly found in North Africa, are the signatures of a return to Africa around 39,000–52,000 ya [8]. This stresses the importance of its detailed study in order to trace one of the earliest Caucasian arrivals to Africa. Although in moderate frequencies, the geographic range of this clade extends from the Near East to the Canary Islands, along the Atlantic shores of Northwest Africa and from the Sahel belt, including Ethiopia, to the southern Mediterranean rim. Out of this area, U6 has only been spotted in the Iberian Peninsula [9-12], Sicily [13], in the north European Ashkenazic Jews [14], and in Ibero-America. The presence in the latter is, most probably, the result of the Spanish and Portuguese colonization [15,16].
In order to construct an unambiguous phylogeny for this clade and infer precise ages for the whole group and for its derivatives, we have fully sequenced eleven mitochondrial lineages representing the main branches of U6. Subsequently, we analyzed the geographic distribution range and relative diversity of these subclades, to deduce their most probable expansion origins based on sequence information of the first hypervariable segment (HVSI) of the mitochondrial control region and on new RFLPs, discovered to be diagnostic for them. Top Abstract Background >Results Discussion Methods Supplementary material References
Results
A new sublineage for U6 Haplogroup U splits from R by mutations 11467, 12308 and 12372. Three branches sprout from this root: U5 (3197, 9477, 13617 and 16270), U6 (3348 and 16172) and the rest of the U clade defined by mutation 1811 [8,17,18]. For this reason, a representative of U5 was chosen as an outgroup.
The phylogenetic tree based on complete mtDNA U6 sequences, confirms that this clade is defined by mutations 3348 and 16172 (Fig. 1). The former can be detected by RFLP analysis using MboI [15]. The existence of three subgroups is also evident. U6a was defined by the presence of HVSI mutations 16172, 16219 and 16278 [4] and now by 7805 and 14179 in the coding region, that can be tested by RFLPs -7802 MaeI and +14179 AccI, respectively. Subgroup U6b was characterized by HVSI mutations 16172, 16219 and 16311 [4], to which mutation 9438 (detectable by RFLP -9438 HaeIII) can now be added. The new clade U6c is defined by HVSI mutations 16169, 16172 and 16189 and at least by mutations 4965 and 5081, that can be tested by RFLPs +4963 Aci I and -5079 Tsp509 I, respectively. In addition, a subgroup, U6a1, has been detected within U6a characterized by the addition of HVSI mutation 16189 [4]. In the same way, HVSI mutation 16163 classifies subgroup U6b1, autochthonous of the Canary Islands [19]. Within the coding region, this subgroup can be further defined by RFLP + 2349 MboI. Figure 1 Figure 1 Phylogenetic tree based on complete U6 mtDNA genome sequences. A U5b individual has been added in order to root the tree. Nomenclature of individuals as in Table 2. Numbers along links refer to nucleotide positions; suffixes are transversions; i insertions (more ...)
From Fig. 1, an important question rises about the constant mutation rate in the coding region. The mean number of substitutions accumulated in U6b lineages (Table 1) is significantly smaller than those in U6a (P = 0.013) and is near significance in U6c (P = 0.058). These differences are mainly due to the number of mutations accumulated in the coding region. Following others [20], we used the likelihood-ratio test [21] to asses whether the mutations accumulated on the different branches were compatible or not with a uniform rate. The difference between the values obtained for the uniform clock model (L0 = -23060.25) and for the variable rate model (L1 = -23032.22), was statistically significant at the 5% level. So, the simpler clock-like tree was rejected. On the other hand, the substitution ratio between coding vs. HVSI region is double in U6a than in U6b or U6c (Table 1). Furthermore, taking into account the ratio of synonymous vs. non-synonymous substitutions in the coding region, again the U6a value doubles that of U6b or U6c, reaching a significant level (P = 0.0237, in a two-tailed Fisher exact test). Both selection and stochastic processes have to be invoked to satisfactorily explain these data. A bias in lineage sampling is the most probable cause of the different substitution ratios between D-loop and coding regions: the U6b and U6c lineages were chosen for their different geographic origin and, comparatively, large divergence in HVSI, whilst for U6a we chose central representatives of the different subclusters excepting that of the Canary Islands. In relation to the differences in synonymous vs. non-synonymous ratios, they could be attributed to the action of purifying selection, having a stronger effect on the older U6a lineages. From this, we deduced that both U6b and U6c spread more recently. Finally, the apparent differences in substitution rates between U6b and U6a or U6c could better be the result of genetic drift, so that the founder lineage that originated the U6b subgroup was less evolved than those that originated U6a and U6c. However, we have to point out that in a similar case, in which significant differences were found in the number of mutations accumulated on two clades of haplogroup L2, selection was suggested as the most probable cause [20]. Table 1 Table 1 Mean number of substitutions, from the base of U6, for the three subgroups of U6 calculated for the twelve complete sequences.
Geographic distribution of U6 lineages Fig. 2 shows the reduced median network obtained from the 56 U6 haplotypes found for the HVSI region between positions 16086–16370. The basal motif for haplogroup U6 has varied as new data have been added. Algerian sequences [9] suggested that the ancestral sequence harbored mutations 16172 16189. Additional data [4] considered 16172 16219 as the most probable ancestral motif. However, the complete sequence of the individual with this motif relocates it in U6a, presenting a back mutation in HVSI position 16278. Our data points to 16172 as the only substitution present in the basal motif. Unfortunately, the high recurrence of this mutation makes it insufficient to diagnose this haplogroup. The highest frequencies for haplogroup U6 as a whole are found in Northwest Africa (Table 2), with a maximum of 29% in the Algerian Berbers [9]. Subgroup U6a and its derivative U6a1 present the widest geographic distribution, from the Canary Islands in the West, to Syria and Ethiopia in the East, and from the Iberian Peninsula in the North, to Kenya in the South. In contrast, U6b shows a more limited and patched distribution, restricted to western populations. In the Iberian Peninsula, U6b is more frequent in the North whilst U6a is prevalent in the South. In Africa, it has been sporadically found in Morocco and Algeria in the North, and Senegal and Nigeria in the South, pointing to a wider distribution in the past, or to gene flow from a geographic focus which has still not been sampled. Curiously, two Arab Bedouins [22] with the same haplotype (16111 16172 16219 16311 16362), are the only Eastern representatives classified as U6b. It would be very interesting to test the 9438 HaeIII restriction enzyme to confirm this classification. Furthermore, subgroup U6b1 characterized by mutation 16163, is restricted to the Canarian Archipelago and the Iberian Peninsula. The geographic distribution of the new subgroup U6c, characterized by the basic motif 16169 16172 16189, is even more localized. It has only been found in the Canary Islands and Morocco. It could also be present in Algeria, if the two individuals with haplotype 16172 16189 16234 16311 [9], classified as U* by RFLP analysis [5], belong to this subgroup. Like for U6b, an autochthonous U6c subcluster (characterized by mutation 16129) was also detected in the Canarian Archipelago. Figure 2 Figure 2 Reduced median network relating HVSI sequences of subhaplogroup U6. The central motif (star) differs from rCRS [55,56] at position 16172. Population codes as in Table 2. Numbers along links refer to nucleotide positions minus 16000; suffix indicates a (more ...) Table 2 Table 2 List of populations used in this study. Population codes are given, as well as sample size, number of U6 haplotypes detected, percentage of U6 in the sample, and the relative frequency (%) of the three U6 sub-groups.
Relationships between areas Linearized FST values distinguished three significantly differentiated geographical areas: Continental Africa, the Iberian Peninsula and the Canary Islands (Table 3). Nucleotide diversities within areas (Table 3) ranged from 3.253 in the Iberian Peninsula to 2.059 in East Africa. At first sight, it is striking that diversities are larger in the Canary Islands and Iberia than in Africa. We think that demographic processes are responsible of this situation. In Africa, the geographic and social isolation of the different Berber groups [23], could have promoted a loss of diversity by genetic drift. On the contrary, the presence in the Canary Islands and Iberia of representatives of all, or nearly all, U6 subclades, some of them not detected nowadays in the Continent, strongly point to the existence of several migratory waves from Africa, possibly at different times, which have increased their variability. This explanation is reinforced when the number of segregating sites (S) are taken into account. This value is larger in West Africa (5.10 ± 1.5) than in the Canaries (2.60 ± 1.0) and the Iberian Peninsula (3.90 ± 1.4), but East Africa presents a lower value (3.2 ± 1.4). The fact that U6b and U6c have a restricted western distribution undoubtedly contributes to this Continental difference. However, the younger U6a1 branch contradicts this general trend. For this subclade, East and West Africa are statistically differentiated (P = 0.016), and the former presents a higher nucleotide diversity (1.55 ± 1.11) than the latter (0.98 ± 0.75). Geographic distributions and diversity values of U6 are congruent with a western origin and radiation for all subclades excepting U6a1 that, most probably, had an eastern origin. Table 3 Table 3 Linearized FST values between areas (below diagonal) and π diversities within areas (on diagonal).
Radiation ages Radiation ages for U6 and its subclades have been estimated on the basis of complete coding and HVSI sequences (Table 4). In general, ages obtained from HVSI are larger than those deduced from the coding region. Both approaches present inconveniences for the time estimates. It has been demonstrated that the coding region has evolved at a roughly constant rate [24]. However, as relatively few clades are fully sequenced, stochastic and/or intentional sampling may bias the representation of the chosen lineages. On the other hand, HVSI estimations are based on a large number of individuals minimizing sampling errors. However, we deal with a short sequence that has not evolved at a constant rate across all human lineages [24]. Furthermore, from the phylogeny of complete U6 sequences (Fig. 1), it has been deduced, once more, that empirical time estimations are not independent of the demographic history of the population sampled. Therefore, we have taken coalescence ages only as rough time frames into which lineage expansions could have occurred. Adopting a conservative position we have used ages based on the coding region whenever possible. Table 4 Table 4 Estimated ages (years) for different subgroups of U6 haplogroup, based on coding and HVSI regions. Top Abstract Background Results >Discussion Methods Supplementary material References
Discussion
African U6 origin and expansions Discarding the Canary Islands, because the most ancient human settlement seems to be no earlier than 2,500 ya [25], and the Iberian Peninsula, because there are no consistent traces of U6 lineages in Europe, Northwest Africa is left as the most probable place from where the African U6 subclades radiated. Another point is to decide whether the proto-U6 ancestor was also of African origin. Although it cannot be completely excluded, this hypothesis seems highly improbable even invoking strong bottlenecks in African populations. It is clear that the whole haplogroup U is an offshoot of macrohaplogroup N. This lineage, together with macrohaplogroup M, were the only ones that, belonging to the star radiation of L3 in Africa, left this continent to colonize Eurasia. Five mutations separate N from the root of the African L3 [8], and there are only late evolved N lineages in Africa, whereas representatives of the full N radiation are present in Eurasia. Thus, this continent would be the logical homeland of the proto-U6 that came back to Africa and spread in its northwest area around 30,000 ya (Table 4). Its most probable route had to be through East Africa. So, the loss of variability in this area is puzzling, although posterior demic expansions affecting East Africa might be the cause. This date roughly corresponds to the Paleolithic occupation of the Maghrib by the Iberomaurusian culture and to the age of the evolved Homo sapiens sapiens skeletons found in this area. Only one of the three U6 subclades, U6a, experienced a great geographic radiation spreading west to the Atlantic shores and east, crossing Africa, to the Near East. A posterior offshoot of this clade, U6a1, has a similar distribution. The upper bound for these expansions are around 28,000 and 17,000 ya, respectively (Table 4). Genetic diversities are congruent with a west to east expansion for U6a and a more probable east to west expansion for U6a1. Furthermore, the absence of U6b and U6c lineages in the East suggests that the population from which the U6a colonizers originated also lacked these lineages or presented them in very low frequencies. The fact that 5 of the 8 U6a haplotypes detected in the Near East are unique of this area (Fig. 2), points to prehistoric demic movements as the most probable cause of the U6a Africa to Asia migration, although historic events cannot be completely ruled out. In frame with the estimated age of U6a are archaeological data supporting early migrations from Africa into the Near East [26]. The expansion of Caucasians in Africa has been correlated with the spread and diversification of Afroasiatic languages. There are different hypothesis to explain the Afroasiatic origin. For some, it would be the result of a Neolithic demic diffusion from the Near East to Africa [27,28]. For others, the Afroasiatic originated in Africa and had a posterior demic spread to West Asia [29,30]. A third possibility is that Afroasiatic languages spread mostly through cultural contacts either from Africa or from Asia [31]. Only demic diffusions could be correlated with U6 expansions detected here. Since an upper bound of 15,000 ya has been estimated for the proto-Afroasiatic origin, it seems that the coalescence age for U6a predates by far the origin of the Afroasiatic phylum. However, the recent spread of U6a1 is more in frame with the emergence of a proto-Afroasiatic language. This U6a1 expansion would favor an East African origin for the Afroasiatic and a posterior expansion to West Africa and West Asia. However, a Near Eastern origin, most probably predating the Neolithic expansion, cannot be ruled out.
Iberian U6 origin and expansions In Europe, U6 lineages have been consistently sampled only in the Iberian Peninsula. It has been mentioned that U6 nucleotide diversity is higher in Iberia than in Africa [12]. This has been confirmed here (Table 3). However, S is greater in West Africa. Considering the isolation of the different Berber groups we think that, in this case, the latter is a better diversity measure. The absence of U6 representatives in the rest of Europe, is also an argument against the hypothesis that these lineages could have migrated to North Africa from Europe. Naturally, this does not exclude that other mitochondrial lineages could have followed this route. Most probably, the presence of these African lineages in Iberia is the result of northward expansions from Africa. The time of this expansion has been predominantly attributed to either the Arab/Berber occupation that lasted seven centuries [10] or to prehistoric immigrations of North Africans to Iberia [12]. Both processes could have contributed to model the U6 landscape in Iberia. First, haplotype matches show that 10 of the 19 U6 lineages detected in Iberia are not present in Africa (Fig. 2), which points against only one recent immigration. Second, the geographic distribution of the U6 lineages in Iberia is puzzling. Whereas the U6b lineages, nowadays very scarce in Africa, are mainly detected in the Northwest, the U6 lineages found in highest frequencies in Africa are predominant in the south, where the Islamic rule lasted longer. At the light of these results we propose that U6b in Iberia is the signal of a prehistoric North African immigration that could have also brought some U6a lineages. Its actual northern range could be the result of a forced retreat due to the arrival of new southern incomers to Iberia. However, the U6a distribution is better explained as the result of more recent gene flow from North Africa. The age of U6b (approx. 10,000 ya) might be considered as an upper bound for the prehistoric wave. Curiously, around this time the Iberomaurusians began to be displaced by the incoming Capsian culture in the Maghrib. On archaeological grounds, it has been proposed that Iberomaurusians slowly retreated towards the Atlantic coast from where they sailed to the Canary Islands and southwards to the Malinese Sahara [2]. Coincidentally, these are the same places where the U6b lineages have been spotted (Fig. 2).
Canary Islands U6 origin and expansions At a genetic level, the Berber origin of the Guanches, the aboriginal population of the Canary Islands, and their survival after the Spanish occupation, has been inferred from the high frequency of U6 lineages in its modern population (Table 2), similar to that of North Africa [19,32]. This fact has been recently confirmed in a mtDNA sequence study on aboriginal remains [33]. It was found that in the Guanche maternal gene pool, U6b1 and U6a were present at frequencies of 8.22% and 1.37%, respectively. U6c was probably also present in the aboriginal pool as a haplotype (16129 16169 16172 16189), now known to belong to subhaplogroup U6c, was proposed as a probable Canarian founder type [19]. As in Northwest Iberia, U6b was the dominant U6 subclade carried by the North African settlers of the islands. All three subclades are present in the modern Canarian population at frequencies of 1.3%, 13.0% and 3.3% for U6a, U6b and U6c, respectively, which is indicative of a broad aboriginal component in the present maternal pool. Perhaps, the comparatively higher frequency of U6a lineages might be attributed to an additional Berber input as result of the slave trade after the Spanish conquest [34,35]. What remains enigmatic of the indubitable North African prehistoric colonization of the Archipelago is that it was carried out by people whose U6 lineages mainly belonged to the U6b subclade that has only been spotted in very low frequencies in the modern African populations of Morocco, Algeria, Senegal and Nigeria (Table 2). Moreover, the U6b and U6c insular haplotypes belong to the autochthonous U6b1 and U6c1 branches differing by substitutions 16163 and 16129, respectively, from all their African counterparts. As the most probable arrival of the first prehistoric Canarian settlers was around 2,500 ya, it is highly improbable that these mutations occurred on the islands. Therefore, we expected to find these Canarian lineages in some place of Africa. However, after extensive sampling they have still not been detected. It is possible that they are present somewhere in low frequencies but, in any case, this phylogeographic distribution suggests that Northwest Africa suffered important demic displacements in the past.
Besides U6, other genetic markers such as 110(-) haplotype of the CD4/Alu system [36], and the M81 Y-chromosome binary marker [6,7], point to an ancient and autochthonous human presence in Northwest Africa. An eastward decline in M81 frequencies has been detected, regrettably the lack of extensive intra-M81 microsatellite diversity studies in Africa precludes phylogeographic comparisons as those done with mtDNA. There are other coincidences between mtDNA data and other systems. For instance, using classical genetic markers, it was found that the Iberian Peninsula showed smaller genetic distances with East Africa than with West Africa [37]. The same pattern was observed for Y-chromosome studies [7], both in line with our results (Table 3). More studies with other genetic markers are necessary to corroborate, complement or even contradict the proposed U6 landscape.
In summary, the phylogeography, nucleotide diversity, and coalescence ages of U6 lineages show that this clade came back to Africa in Paleolithic times. Its most probable origin was the Near East and not Europe, and since then, its presence in North Africa has been permanent. The focus of the first African expansion, detected by the spread of U6a, was Northwest Africa reaching the Near East also in the Paleolithic. The posterior U6a1 radiation most probably occurred in Northeast Africa again extending to the Near East. This movement is correlated in time with the attributed origin and expansion of Afroasiatic languages. This U6a1 wave also arrived to the Maghrib, the Northwest African margin, where the more localized U6b and U6c lineages were spreading. This movement is in time frame with the Capsian culture. Based on archaeological and anthropological grounds, it has been speculated that these incomers slowly pushed away the aboriginal residents [2]. It could be in that time when U6b reached the south of the Iberian Peninsula from where it was displaced to the north where it persists today. The U6b and U6c diaspora also reached the Atlantic fringe from where they sailed to the Canary Islands. Two autochthonous U6 lineages (U6b1 and U6c1), present today in the islands, attest the survival of those aboriginal North Africans until nowadays. The fact that these Canarian lineages have not been detected in Africa and that, in contrast to the ubiquitous U6a and U6a1, the U6b and U6c lineages are scarcely spotted in present African populations, may be clues of past important demographic movements in this western area. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=270091Posts: 169 | Registered: Apr 2007
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Also: Sean Myles1, 2 Contact Information, Nourdine Bouzekri1, Eden Haverfield1, 3, Mohamed Cherkaoui4, Jean-Michel Dugoujon5 and Ryk Ward1 (1) Institute of Biological Anthropology, University of Oxford, Oxford, UK (2) Department of Evolutionary Genetics, Max-Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103, Leipzig, Germany (3) Department of Human Genetics, University of Chicago, 920 East 58th Street, Chicago, IL 60637, USA (4) Laboratoire drsquoEcologie Humaine, Faculté des Sciences-Semlalia, Université Cadi Ayyad, Morocco (5) Centre drsquoAnthropologie CNRS,, University of Toulouse, UMR 8555, France
Abstract The process by which pastoralism and agriculture spread from the Fertile Crescent over the past 10,000 years has been the subject of intense investigation by geneticists, linguists and archaeologists. However, no consensus has been reached as to whether this Neolithic transition is best characterized by a demic diffusion (with a significant genetic input from migrating farmers) or a cultural diffusion (without substantial migration of farmers). Milk consumption and thus lactose tolerance are assumed to have spread with pastoralism and we propose that by looking at the relevant mutations in and around the lactase gene in human populations, we can gain insight into the origin(s) and spread of dairying. We genotyped the putatively causal allele for lactose tolerance (–13910T) and constructed haplotypes from several polymorphisms in and around the lactase gene (LCT) in three North African Berber populations and compared our results with previously published data. We found that the frequency of the –13910T allele predicts the frequency of lactose tolerance in several Eurasian and North African Berber populations but not in most sub-Saharan African populations. Our analyses suggest that contemporary Berber populations possess the genetic signature of a past migration of pastoralists from the Middle East and that they share a dairying origin with Europeans and Asians, but not with sub-Saharan Africans.
Contact Information Sean Myles Email: myles@eva.mpg.de Phone: +49-341-3550543 Fax: +49-341-3550555
More: Genetic variation in North Africa and Eurasia: Neolithic demic diffusion vs. paleolithic colonisation Guido Barbujani 1 2 *, Andrea Pilastro 2, Silvia De Domenico 2, Colin Renfrew 3 1Dipartimento di Scienze Statistiche, Università di Bologna, I-40126 Bologna, Italy 2Dipartimento di Biologia, Universita' di Padova, I-35121 Padova, Italy 3Department of Archaeology, University of Cambridge, Cambridge CB2 3DZ, UK
*Correspondence to Guido Barbujani, Dipartimento di Biologia, via Trieste 75, I-35121 Padova, Italy
Keywords Gene frequencies • Languages • Gene flow • Cultural transmission • Spatial autocorrelation
Note, the expansion was from Africa, into West Asia as well as Southwest Europe.
quote:The foolish troll wrote: Not really. Some would and some wouldn't. (call modern SSA black)
LOL Only nutcases like you would not call indigenous Sub-Saharan Africans 'black'! LOLPosts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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Only nutcases in the past called anyone Negroid, but those nutcases did not call KhoiSan that. Now nutcases in the present try to call them Black.
Posts: 169 | Registered: Apr 2007
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One of the biggest misconceptions is that Khoisan are all light (yellow-lieghtbrown) skinned, and all other Africans are somehow 'black', and descended from Bantu.
Anyone outside of that definition is not a black african.
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^ Which is silly because Khoisan evolved light skin in southern Africa farther from the equator, yet the majority of African populations lived around the equator and it is in equatorial regions that the first human populations evolved and in which the first humans left African (out of the Horn). Thus to deny that these populations were 'black' is ludicrous. Besides, even the 'lighter-skinned' Khoisan are still considered 'black' in social circles!
Jaimie is just a negro-phobe with issues. Let banned trolls be banned... Unless he comes back again!
Posts: 26252 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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UBBFriend: Email this page to someone!
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So I ask, where are Arwa's answers to the above discrepancies as pointed out by Evergreen?
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