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Unfortunately I'm not able to access the full text of the Haaretz article since I am not subscribed. But I take it that this is the study being discussed?
Tukuler
multidisciplinary Black Scholar
Member # 19944
posted
Coupla Egypt centered REDUXes from "Brandon's" preprint.
How many times have some ESers 'blanketedly' dismissed similar logic transfers? Well, can employ 'em now that Simon Sez logical transference is valid. That is, if it survives peer review and sees print.
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They are basically regurgitating things we already know and rehashing some of the erroneous conclusions made in other papers. At issue in all of these papers is they are trying to reconstruct a DNA history based on current DNA going back 100,000 years which is impossible. The first problem being that you only see the lineages that survived,not the ones that died off or were replaced. The second issue being that there is no ADNA from Africa over 8,000 years old, which means any DNA study in this region is always going to be skewed toward ADNA samples from Europe. So it isn't really a DNA history as opposed to a statistical model for the history and evolution of the DNA samples they used which is by no means representative of the ancient population histories of the middle east. Keep in mind that when you talk of population clusters going back over 10,000 years you are mostly talking about populations of maybe a few hundred to a thousand people. So factoring that in with the fact that these people were mobile you see that it is exponentially impossible to tell who was where and when over such a large time span. Present populations cannot tell you that because it implies continuity of a single group or even multiple groups going back over tens of thousands of years which is also illogical and impossible.
The irritating part of all of this is that all these papers start with Africa, but refuse to label those original populations in Eurasia as Africans. Almost all of them try and impose this idea of "sex breeding camps" just outside the African border implying all migrating Africans all magically mated with Neanderthals. And then they totally drop any African lineages out of the population history and go on to talk about East Asia, Central Asia and Europe as major hubs for human origins, without talking about how the African genes changed into Eurasian genes or how the African lineages evolved into various Eurasian lineages. Then they always jump forward to the present and use those Eurasian population clusters as the basis for modeling genetic lineages in the modern DNA samples. It is always the same flow and is all predicated on the existing large body of ADNA samples from Eurasia, the lack of ADNA from Africa, large amounts of Neanderthal ADNA , Laziridis' Basal Eurasian and the "neanderthal mixture" model that is popular currently in Genetics research.
quote: Scientists have sequenced the oldest Homo sapiens DNA on record, showing that many of Europe’s first humans had Neanderthals in their family trees. Yet these individuals are not related to later Europeans, according to two genome studies of remains dating back more than 45,000 years from caves in Bulgaria and the Czech Republic1,2.
The research adds to growing evidence that modern humans mixed regularly with Neanderthals and other extinct relatives, says Viviane Slon, a palaeogeneticist at the University of Tel Aviv in Israel. “It’s different times, different places, and it happens again and again.”
The genetic history of the earliest humans in Europe and Asia has been blurred. Although researchers have sequenced DNA from Neanderthals and other extinct human relatives dating as far back as 430,000 years, there is a scarcity of genetic information from the period between around 47,000 and 40,000 years ago, known as the Initial Upper Palaeolithic, and no Homo sapiens DNA at all from before this period. Genomes belonging to humans from Siberia and Romania showed no connection to later waves of Europeans, but a 40,000-year-old individual from China is a partial ancestor of modern East Asian people.
Like all present-day people whose ancestry isn’t solely African, these early Eurasians carried Neanderthal DNA. Researchers thought that probably originated from mixing between the groups in the Middle East 50,000–60,000 years ago. But a 2015 study3 of the genome of the 40,000-year-old Romanian individual, from a site called Peștera cu Oase, held a surprise: a Neanderthal ancestor in the past four to six generations, suggesting that humans interbred with Neanderthals in Europe, too.
Given the bolded above, how do they know that all human populations going back over 50,000 years did not have Neanderthal ancestry as a result of being on the same evolutionary tree? A lot of these conclusions are simply ridiculous. But reinforces the point they cannot say what the DNA package was associated with OOA and without that, you really cannot model ancient population histories.
At this point I would just ignore any paper talking about ancient human DNA history that isn't using any ADNA from across multiple locations in Africa and the Middle East of any considerable time depth over 5,000 years old. Because the results are only going to reflect the available data and existing interpretations of said data.
In many ways this is simply verbally restating the same human laziridis DNA tree which magically branches African off from non African as co-equal entities and led to this whole concept of ghost populations and Basal Eurasian.
quote: The large number of physically-phased haplotypes allowed us to study population history from relatively old periods (>100 kya) to very recent times (1 kya). We find no evidence that an early expansion of humans out of Africa has contributed genetically to present-day populations in the region. This finding adds to the growing consensus that all contemporary non-African modern humans descend from a single expansion out-of-Africa, quickly followed by admixture with Neanderthals, before populating the rest of the world (Mallick et al., 2016; Bergstrom et al., 2020). We find that Middle Eastern populations have very little Neanderthal DNA that is private to the region, with the vast majority shared with other Eurasians. We demonstrate that Arabian populations have lower Neanderthal ancestry than Levantine, European and East Asian populations and attribute this difference to elevated ancestry from a basal Eurasian population, which did not admix with Neanderthals, in addition to recent African admixture.
These people don't even know the DNA lineages of the OOA populations which means they cannot model accurately any human DNA history without it.
The fundamental issue is that these researchers and scholars are trying to promote the fallacy that we can understand human population and DNA history SOLELY by looking at current populations and current DNA patterns. This is impossible, especially with the world being more connected and populations being able to travel and interact across long distances. Any genealogical research going over such large distances cannot take into account individual family histories and their individual geographic and distributions over time. All of these models are based on the assumption of fixed population groups that have remained in place for over 10,000 years which is simply false.
Posts: 8889 | Registered: May 2005
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posted
As for Levantines and Arabians having different origins, the archaeology seems to support this with Levantine influence reaching mainly the Hejaz (western Arabia) during the Neolithic and Bronze Ages. As for the ancestry proportion models, LOL yeah it looks like what a lot of people on this forum have been saying for years!
-------------------- Mahirap gisingin ang nagtutulog-tulugan. Posts: 26236 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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Figure 3 A possible model for the population formation in the Middle East Populations in ellipses are sampled populations, while populations in boxes are hypothetical. Worst f-statistics: Z score = −2.9.
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We explore models further in Figure S3. BA, Bronze Age; HG, hunter-gatherer.
Figure S3. qpGraph alternative models for population formation in the Middle East and automatically fitting admixture graphs, related to Figure 3
Graphs (A) and (B) show alternative scenarios for populating the Middle East. Changes from the best model (Figure 3) involve (A) Arabians derive their ancestry from a population related to ancient Iranians and local hunter-gatherers. (B) Ancestry in Arabia from a Levant_N-related rather than Natufian-related population. (C) We show a semi-automatically fitted graph. We started with a base-graph of the ancient populations based on previous knowledge (Lazaridis et al., 2016; Haber et al., 2017); this graph has an outlier Z-score = 2.06. We then used qpBrute (Ní Leathlobhair et al., 2018; Liu et al., 2019) to fit the EmiratiA and we obtained a graph with no outliers showing EmiratiA descended from a mixture of Natufian-related and Sidon_BA-related ancestries. We then used this new graph as a base and added the modern Lebanese. We found that the graph with the lowest Z-score shown here was identical to our Figure 3.
The genomic history of the Middle East Article Aug 2021 Mohamed A Almarri Marc Haber
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Abstract North Africa is a key region for understanding human history, but the genetic history of its people is largely unknown. We present genomic data from seven 15,000-year-old modern humans from Morocco, attributed to the Iberomaurusian culture. We find a genetic affinity with early Holocene Near Easterners, best represented by Levantine Natufians, suggesting a pre-agricultural connection between Africa and the Near East. We do not find evidence for gene flow from Paleolithic Europeans into Late Pleistocene North Africans. The Taforalt individuals derive one third of their ancestry from sub-Saharan Africans, best approximated by a mixture of genetic components preserved in present-day West and East Africans. Thus, we provide direct evidence for genetic interactions between modern humans across Africa and Eurasia in the Pleistocene.
Conclusion: The Taforalt individuals averaged 22.5% sub-Saharan African ancestry, ... shows the Natufians as 37% WHG-like and 63% Basal Eurasian like ancestry
^ Taforalt's position clusters with modern Afar and next to a modern Yemeni.
-------------------- Mahirap gisingin ang nagtutulog-tulugan. Posts: 26236 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Conclusion: The Taforalt individuals averaged 22.5% sub-Saharan African ancestry, ... shows the Natufians as 37% WHG-like and 63% Basal Eurasian like ancestry
This is double speak. 37% WHG + 63% BE means that ancestry represented by Taforalt in west and East Africans is basal Eurasian. That literally contradicts the philosophy of Basal Eurasian.
Posts: 1781 | From: New York | Registered: Jul 2016
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^ Sorry for the confusion of that incomplete quote. It is the Natufians who show 37% WHG ancestry and 63% Basal Eurasian ancestry. Taforalt in turn shows 36.5% Sub-Saharan ancestry and 63.5% Natufian ancestry, showing that Taforalt are the result of admixture between Sub-Saharans and allegedly immigrant Natufians. By the way, the particular type of Sub-Saharan ancestry Taforalt has predates that found in modern West and East Africans which comes to show how diverse "Sub-Saharan" ancestry is.
quote:Originally posted by Doug M: T The second issue being that there is no ADNA from Africa over 8,000 years old, which means any DNA study in this region is always going to be skewed toward ADNA samples from Europe.
This is patently false. Hora (Malawi), Shum Laka (Cameroon) and Taforlat (Morocco) ancient genetic samples are all over 8000 years old.
Posts: 2463 | From: New Jersey USA | Registered: Dec 2007
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