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Haplogroup_R1b_World
300px-Hamito-Semitic_languagesIf you follow Y genealogy you know that the distribution of R1ba2 exhibits a peculiar pattern. R1b is the most common haplgroup in Western Eurasia, and shares a deep common ancestry with R1a. It seems to have risen to high frequencies in Europe only during the Bronze Age, though has been found in earlier periods. But within Africa R1b is found in very high concentrations around Lake Chad. This particular R1b lineage seems to have diverged from other Eurasian branches in the latter portion of the Pleistocene, so one possible consideration is that this was an instance of Eurasian backflow during the Ice Age.

One reason I have been somewhat skeptical of this model is that the Sahara desert was much more extensive and arid during much of the Pleistocene than today. And during this period humans had less cultural technology to endure the rigors of the deep desert. Or, if they did, their population densities were likely much lower, which probably served as an impediment to gene flow.

A new paper in The American Journal of Human Genetics sheds light on what might have been going on here. Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations. The major findings are straightforward. First, much greater sampling of populations, and a better depth/density of marker coverage, allowed the researchers to detect low levels, on the order of ~1%, Eurasian admixture in some Central African groups. This admixture seems to date to the Holocene, ~5,000 to ~7,000 years before the present (they used LD based methods on the autosome). Interestingly, the R1b lineage common in Central Africa also seems to coalesce during this time. Finally, the admixture seems to be closest to Sardinians among extant populations.

The Sardinian affinity of much of African Eurasian admixture may seem peculiar, but it makes more sense when one considers that Sardianians are probably the best modern proxies for the earliest Neolithic farmers from the Eastern Mediterranean. Modern Middle Eastern populations are very different from those which flourished in the prehistory between the rise of agriculture and complex civilizations because of admixture within Middle Eastern groups. The initial push into Africa by the agriculturalists dates to a period before we have a good understanding of the ethnographic balance.

Very high frequencies of R1b in modern Central Africa groups may indicate drift. But another possibility is that the migration was male-mediated. This seems to have been the case in much of Eurasia, so it would not be surprising in this context. The status of these males was such that despite their diminishing genetic impact on overall ancestry, their Y chromosomes, and possibly their language, with varied forms of Afro-Asiatic, persisting down to the present.

Finally, here’s the last paragraph of the discussion:

Our study has shown that human genetic diversity in Africa is still incompletely understood and that ancient admixture adds to its complexity. This work highlights the importance of exploring underrepresented populations, such as those from Chad, in genetic studies to improve our understanding of the demographic processes that shaped genetic variation in Africa and globally.

 
• Category: Science • Tags: Africa, Genetics 
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  1. Shaikorth says:

    Looks like the authors lean towards the idea that R1b-V88 isn’t related to Afro-asiatic language, contra some other studies.

    R1b-V88 was previously found in Central and West Africa and was associated with a mid-Holocene migration of Afro-asiatic speakers through the central Sahara into the Lake Chad Basin. In the populations we examined, we found R1b in the Toubou and Sara, who speak Nilo-Saharan languages, and also in the Laal people, who speak an unclassified language. This suggests that R1b penetrated Africa independently of the Afro-asiatic language spread or passed to other groups through admixture.

    And of course, many AA-speakers more distant from Chad don’t have much in the way of V88.
    Anatolian/Levantine Neolithic as the first Eurasian backflow makes sense in any case. Eventually accompanied by Iranian Neolithic-like ancestry in the east and north.

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    • Replies: @ohwilleke
    It is beyond dispute that R1b-V88 is strongly associated with the Chadic language. And, over 7,200 years, of course, there would be some seepage to neighboring populations (indeed, the remarkable thing is not how much seepage there has been, but how little).

    There is also very good (genetic and linguistic) reason to believe that some early Chadic people were Nilo-Saharans who experienced language shift, and that Chadic is genetically derived from Northern Cushitic languages as speakers of those languages have an mtDNA affinity with Chadic people involving mtDNA L3f.

    The real mystery is how and why R1b-V88 people got from the European steppe at the time that herding arrive there (around 6000 BCE, the same time that it arrived in Egypt, or perhaps a few centuries earlier), to the Fertile Crescent and beyond to the Nile, then down the Nile to the Blue Nile and from there to Northern Ethiopia sometime prior to 5300 BCE (allowing 100 years to take local Cushitic wives and then to travel as nomadic pastoralists upstream along the Blue Nile to the junction with the Yellow Nile and over the ridge in the Lake Chad endorheic basin where Chadic ethnogenesis was completed), without leaving much of a trace anywhere in between.

    What didn't the Natufians do this?

    The 8.2 kiloyear climate event is a plausible push, but why not stop sooner? Did they just keep going until they found people who didn't insist they move along?

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  2. covadonga says:

    Hi,

    I am a former engineer, now working in finance who started reading this blog a year ago i.e. I am an almost complete neophyte to genetics. If I was interested in having my whole genome sequenced: (i) is there a commercial service available to me or do I need to be part of a research project and (ii) which one would you recommend?

    On an unrelated note, since I’ve started reading the blog I have also really enjoyed all the book reviews and recommendations – is there one particular book that you would recommend to someone looking to start reading up on Chinese history?

    Thank you,

    Covadonga

    Read More
    • Replies: @Razib Khan
    https://www.fullgenomes.com/ or veritas.

    is there one particular book that you would recommend to someone looking to start reading up on Chinese history?

    fairbanks.

    please use the 'open thread' for these sorts of comments in future.

  3. @covadonga
    Hi,

    I am a former engineer, now working in finance who started reading this blog a year ago i.e. I am an almost complete neophyte to genetics. If I was interested in having my whole genome sequenced: (i) is there a commercial service available to me or do I need to be part of a research project and (ii) which one would you recommend?

    On an unrelated note, since I've started reading the blog I have also really enjoyed all the book reviews and recommendations - is there one particular book that you would recommend to someone looking to start reading up on Chinese history?

    Thank you,

    Covadonga

    https://www.fullgenomes.com/ or veritas.

    is there one particular book that you would recommend to someone looking to start reading up on Chinese history?

    fairbanks.

    please use the ‘open thread’ for these sorts of comments in future.

    Read More
  4. covadonga says:
    @Razib Khan
    https://www.fullgenomes.com/ or veritas.

    is there one particular book that you would recommend to someone looking to start reading up on Chinese history?

    fairbanks.

    please use the 'open thread' for these sorts of comments in future.

    Thanks! And will do.

    Read More
  5. YFull has the following estimates for R-V88:
    formed 17200 ybp, TMRCA 11800 ybp

    It’s “brother clade” R-L389 is about same age,
    R-L389L389/PF6531 * L388/PF6468formed 17200 ybp, TMRCA 16800 ybp
    (L389 is parent clade of M269 and thus nearly all western Eurasian R1b)

    I wonder if this reflects a spilt in R1b lineage probably somewhere south of Caspian (Iranian plateau?) with R-V88 been south of Caucasus/Caspian and the subclades of R-L389 (M269 and M73) been north in Eurasian steppe. M73 seems concentrated in Turkic groups of Eurasian Steppe and obviously M269 showed up in Yamnaya kurgan remains and seems to expanded into western Eurasia during the Bronze age.

    One of the neolithic farmers sequenced from Spain was R1b, but most likely R1b-V88 (I believe in Reich’s paper).

    Anyways better go read the paper, thanks for the link/analysis.

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  6. @Razib,
    “Very high frequencies of R1b in modern Central Africa groups may indicate drift. But another possibility is that the migration was male-mediated. ”

    R1b-V88 was very unpopular in the Neolithic East Mediterranean. Therefore at some-point drift occurred, whether before their arrival in Central Africa or afterwards.

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  7. dearieme says:

    (assholes who talk shit about me on other blogs not welcome to comment :-] -Razib)

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  8. In my opinion when the Sahara was green there was bi-directional gene-flow. Chad, Algeria/Tunisia/Libya, and Sardinia all have several variants of R-V88 plus African Y-DNA haplogroup A, etc. Plus the highest frequency HLA haplotype in Sardinians among various populations across the whole island is A30-Cw5-B18-DR3-DQ2, which is a very disequilibrated haplotype shared with Berbers, Chadic speakers [eg Podoko or Ouldeme], Senegalese Mandenka, Ghanaians, and Sudanese. The haplotype has several recombinants in Africa, and the alleles which the haplotype is composed from are all found at highest frequency and diversity in the African populations, indicating that the haplotype originated in Africa and not Sardinia.

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  9. ohwilleke says: • Website

    This is consistent with autosomal data from Tishkoff et al, “The genetic structure and history of Africans and African Americans” 22(324) Science 5930 (May 2009) which concluded that:

    We observe the highest proportion of the “Nilo-Saharan AAC [ed. ancestral autosomal genetic component]” in the southern/central Sudanese populations (Nuer, Dinka, Shilluk, Nyimang), with decreasing frequency from northern Kenya (e.g. Pokot) to northern Tanzania (Datog, Maasai). From K = 5-13 [ed. refering to the number of ancestral components], all Nilo-Saharan speaking populations from Kenya, Tanzania, southern Sudan, and Chad cluster with west-central Afroasiatic Chadic speaking populations.

    These results are consistent with linguistic and archeological data, suggesting a possible common ancestry of Nilo-Saharan speaking populations from an eastern Sudanese homeland within the past ~10,500 years, with subsequent bi-directional migration westward to Lake Chad and southward into modern day southern Sudan, and more recent migration eastward into Kenya and Tanzania ~3,000 ya (giving rise to Southern Nilotic speakers) and westward into Chad ~2,500 ya (giving rise to Central Sudanic speakers).

    A proposed migration of proto-Chadic Afroasiatic speakers ~7,000 ya [5000 B.C.E.] from the central Sahara into the Lake Chad Basin may have caused many western Nilo-Saharans to shift to Chadic languages. Our data suggest that this shift was not accompanied by large amounts of Afroasiatic gene flow. Analyses of mtDNA provide evidence for divergence ~8,000 ya [6,000 B.C.E.] of a distinct mtDNA lineage present at high frequency in the Chadic populations and suggest an East African origin for most mtDNA lineages in these populations.”

    It is also consistent with the conclusions of a Cherny (2009) on Chadic mtDNA (which doesn’t bracket the time frame very closely):

    Within the Afro-Asiatic language phylum, the Chadic branch is linguistically close to the East African Cushitic branch although they are separated by ~2,000 km of territory in which different Semitic and Nilo-Saharan peoples live today. We show that only northern Cushitic groups from Ethiopia and Somalia are genetically close to Chadic populations. Thus, the archaeologically and linguistically supported route of proto-Chadic pastoralists via Wadi Howar [the remnant of the ancient Yellow Nile, a tributary of the Nile from about 8000 to 1000 BCE] to the Chad Basin may have genetic support.

    The mtDNA distributions in Northeastern, Eastern and Central Africa tend to follow regional patterns except for one mtDNA L3f clade particular to Chadic peoples and derived from a Cushitic clade (the Cushitic people overwhelmingly live in Ethiopia), and the Chadic languages have relatively stronger linguistic links to Cushitic within the Afro-Asiatic language family than to other Afro-Asiatic languages.

    A 2010 paper on Y-DNA R1b-V88 comes up with a consistent date range whose midpoint is very close to the archaeological data discussed in another paper:

    A worldwide phylogeographic analysis of the R1b haplogroup provided strong support to the Asia-to-Africa back-migration hypothesis. The analysis of the distribution of the R-V88 haplogroup in >1800 males from 69 African populations revealed a striking genetic contiguity between the Chadic-speaking peoples from the central Sahel and several other Afroasiatic-speaking groups from North Africa. The R-V88 coalescence time was estimated at 9.2-5.6 [corrected] kya, in the early mid Holocene. We suggest that R-V88 is a paternal genetic record of the proposed mid-Holocene migration of proto-Chadic Afroasiatic speakers through the Central Sahara into the Lake Chad Basin, and geomorphological evidence is consistent with this view.

    From Cruciani, et al., “Human Y chromosome haplogroup R-V88: a paternal genetic record of early mid Holocene trans-Saharan connections and the spread of Chadic languages.” Eur J Hum Genet. 2010 Jul;18(7):800-7. Epub 2010 Jan 6.

    In terms of dates the most convincing input comes from a 2008 paper: Sereno PC, Garcea EAA, Jousse H, et al. “Lakeside cemeteries in the Sahara: 5000 years of Holocene population and environmental change.” PLoS One. 2008;3:e2995.

    Approximately two hundred human burials were discovered on the edge of a paleolake in Niger that provide a uniquely preserved record of human occupation in the Sahara during the Holocene (~8000 B.C.E. to the present). Called Gobero, this suite of closely spaced sites chronicles the rapid pace of biosocial change in the southern Sahara in response to severe climatic fluctuation. Two main occupational phases are identified that correspond with humid intervals in the early and mid-Holocene, based on 78 direct AMS radiocarbon dates on human remains, fauna and artifacts, as well as 9 OSL dates on paleodune sand.

    The older occupants have craniofacial dimensions that demonstrate similarities with mid-Holocene occupants of the southern Sahara and Late Pleistocene to early Holocene inhabitants of the Maghreb. Their hyperflexed burials compose the earliest cemetery in the Sahara dating to ~7500 B.C.E. These early occupants abandon the area under arid conditions and, when humid conditions return ~4600 B.C.E., are replaced by a more gracile people with elaborated grave goods including animal bone and ivory ornaments.

    The principal significance of Gobero lies in its extraordinary human, faunal, and archaeological record, from which we conclude the following:

    1.The early Holocene occupants at Gobero (7700–6200 B.C.E.) were largely sedentary hunter-fisher-gatherers with lakeside funerary sites that include the earliest recorded cemetery in the Sahara.
    2.Principal components analysis of craniometric variables closely allies the early Holocene occupants at Gobero with a skeletally robust, trans-Saharan assemblage of Late Pleistocene to mid-Holocene human populations from the Maghreb and southern Sahara.
    3.Gobero was abandoned during a period of severe aridification possibly as long as one millennium (6200–5200 B.C.E).
    4.More gracile humans arrived in the mid-Holocene (5200–2500 B.C.E.) employing a diversified subsistence economy based on clams, fish, and savanna vertebrates as well as some cattle husbandry.
    5.Population replacement after a harsh arid hiatus is the most likely explanation for the occupational sequence at Gobero.
    6.We are just beginning to understand the anatomical and cultural diversity that existed within the Sahara during the Holocene.

    The Neolithic revolution appears in Egypt around 6000 B.C.E. and the Egyptian historic record goes back to about 3100 B.C.E., so these dates would be in a pre-historic period in Egypt, after it had adopted farming and herding, but before it had adopted writing, which explains why there is no historical record of their migration.

    Identifying the proto-Chadic people with the humans who arrived at Gobero on the shores of Lake Chad around 5200 B.C.E. is a good fit for all of the data. And genetics and archaeology also tell us a lot about how they got to their final destination.

    Proto-Chadic men (with Y-DNA R1b-V88) took Cushitic women as wives (probably no earlier than about 6000 B.C.E. when herding reaches Egypt) and then migrated West to Lake Chad where they arrive around 5200 BCE.

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  10. ohwilleke says: • Website
    @Shaikorth
    Looks like the authors lean towards the idea that R1b-V88 isn't related to Afro-asiatic language, contra some other studies.

    R1b-V88 was previously found in Central and West Africa and was associated with a mid-Holocene migration of Afro-asiatic speakers through the central Sahara into the Lake Chad Basin. In the populations we examined, we found R1b in the Toubou and Sara, who speak Nilo-Saharan languages, and also in the Laal people, who speak an unclassified language. This suggests that R1b penetrated Africa independently of the Afro-asiatic language spread or passed to other groups through admixture.
     
    And of course, many AA-speakers more distant from Chad don't have much in the way of V88.
    Anatolian/Levantine Neolithic as the first Eurasian backflow makes sense in any case. Eventually accompanied by Iranian Neolithic-like ancestry in the east and north.

    It is beyond dispute that R1b-V88 is strongly associated with the Chadic language. And, over 7,200 years, of course, there would be some seepage to neighboring populations (indeed, the remarkable thing is not how much seepage there has been, but how little).

    There is also very good (genetic and linguistic) reason to believe that some early Chadic people were Nilo-Saharans who experienced language shift, and that Chadic is genetically derived from Northern Cushitic languages as speakers of those languages have an mtDNA affinity with Chadic people involving mtDNA L3f.

    The real mystery is how and why R1b-V88 people got from the European steppe at the time that herding arrive there (around 6000 BCE, the same time that it arrived in Egypt, or perhaps a few centuries earlier), to the Fertile Crescent and beyond to the Nile, then down the Nile to the Blue Nile and from there to Northern Ethiopia sometime prior to 5300 BCE (allowing 100 years to take local Cushitic wives and then to travel as nomadic pastoralists upstream along the Blue Nile to the junction with the Yellow Nile and over the ridge in the Lake Chad endorheic basin where Chadic ethnogenesis was completed), without leaving much of a trace anywhere in between.

    What didn’t the Natufians do this?

    The 8.2 kiloyear climate event is a plausible push, but why not stop sooner? Did they just keep going until they found people who didn’t insist they move along?

    Read More
    • Replies: @Shaikorth
    Yes, Sub-Saharan V88 is associated with Chadic now (and everyone around that region), but was it associated with a possible Chadic-Cushitic origin, or with original Afroasiatics? This is a bit like "was R1b-M269 associated with the ancestral language family of the Basques"? Cushitics don't show much V88, the samples from this study have none.
  11. ohwilleke says: • Website

    The Proto-Chadic people, by the way, were not Natufians as we can now discern from ancient DNA. Per Wikipedia:

    According to ancient DNA analyses conducted by Lazaridis et al. (2016) on six Natufian skeletal remains from present-day northern Israel, the Natufians carried the Y-DNA haplogroup E-Z830, which is ancestral to the E1b1b-M123 paternal clade. One Natufian individual was also found to belong to the N1b mtDNA haplogroup. In terms of autosomal DNA, these Natufians carried high frequencies of the Basal Eurasian component, but were slightly distinct from the northern Anatolian populations that contributed to the peopling of Europe.

    citing Lazaridis, Iosif; et al., “The genetic structure of the world’s first farmers” (biorxiv 17 June 2016).

    Read More
  12. Shaikorth says:
    @ohwilleke
    It is beyond dispute that R1b-V88 is strongly associated with the Chadic language. And, over 7,200 years, of course, there would be some seepage to neighboring populations (indeed, the remarkable thing is not how much seepage there has been, but how little).

    There is also very good (genetic and linguistic) reason to believe that some early Chadic people were Nilo-Saharans who experienced language shift, and that Chadic is genetically derived from Northern Cushitic languages as speakers of those languages have an mtDNA affinity with Chadic people involving mtDNA L3f.

    The real mystery is how and why R1b-V88 people got from the European steppe at the time that herding arrive there (around 6000 BCE, the same time that it arrived in Egypt, or perhaps a few centuries earlier), to the Fertile Crescent and beyond to the Nile, then down the Nile to the Blue Nile and from there to Northern Ethiopia sometime prior to 5300 BCE (allowing 100 years to take local Cushitic wives and then to travel as nomadic pastoralists upstream along the Blue Nile to the junction with the Yellow Nile and over the ridge in the Lake Chad endorheic basin where Chadic ethnogenesis was completed), without leaving much of a trace anywhere in between.

    What didn't the Natufians do this?

    The 8.2 kiloyear climate event is a plausible push, but why not stop sooner? Did they just keep going until they found people who didn't insist they move along?

    Yes, Sub-Saharan V88 is associated with Chadic now (and everyone around that region), but was it associated with a possible Chadic-Cushitic origin, or with original Afroasiatics? This is a bit like “was R1b-M269 associated with the ancestral language family of the Basques”? Cushitics don’t show much V88, the samples from this study have none.

    Read More
  13. ohwilleke says: • Website

    Chadic probably postdated Cushitic

    The model that makes sense to me is that Cushitic predates Chadic. If Y-DNA R1b-V88 were part of the founding population of Cushitic people, it would be present in Cushitic populations in more than trace amounts, which it is not. Chadic men, meanwhile lack both Y-DNA T and Y-DNA E1b1b in significant amounts. From a Y-DNA perspective, they are true outsiders. They picked up Cushitic wives and were influenced by Cushitic languages without leaving a genetic legacy in East Africa – the whole proto-Chadic community left for Lake Chad together.

    There is really no otherwise way to understand a Chadic language origin that makes any sense. No place that R1b-V88 could have come from would have been within the range of the Afro-Asiatic languages at any point in history and they are associated with any other language group, so they must have experienced language shift to Chadic. Chadic was probably a result of substrate influences of Y-DNA R1b-V88 men acquiring Cushitic as a second language and changing that language in the process.

    Y-DNA T was probably an earlier Neolitic arrival to Afro-Asiatic Africa

    Phylogeny and geography, taken together, clearly put the origins of Y-DNA T outside of Africa.

    One of the distinctive Y-DNA haplogroup in a lot of Cushitic populations is Y-DNA T and that clade almost certainly back migrated via the Levant and down the Nile to Ethiopia and Somalia, and had much more of a demographic impact all of the way up and down the Nile basin. The Gate of Tears route from Arabia for Y-DNA T in Africa is strongly disfavored because clades of Y-DNA T in Arabia have TMRCA of about 1,600 years ago v. 11,000ish for those in Egypt and East Africa which most Y-DNA T in Africa is found.

    The Wikipedia survey of the frequency of Y-DNA T in Africa when I last looked showed 108 instances within Afro-Asiatic populations surveyed (mostly Egypt, Ethiopia and Somolia) and 26 instances of non-Afro-Asiatic peoples with 19 of those instances in three populations: 15 (of 256) individuals in the Spanish Canary Islands that trace roots to North Africa and were almost surely settled by Berbers during the Roman era, 6 (of 34) individuals in the Bantu speaking South African Lemba who claim to have have Jewish roots (which genetics tends to confirm), and 3 (of 17) of the Niger-Congo speaking Fulbe in Northern Cameroon right on the Afro-Asiatic and Niger-Congo population boundary in Africa.

    There were only seven other individuals in all of Africa with Y-DNA T in all of the populations that have been surveyed (and the Wikipedia list is while not a complete set of the literature, a summary of a very good share of the entire literature) out of 134 African surveyed with Y-DNA T in all. There were three isolated cases in small Bantu populations, and four involving small percentages in Nilotic populations, and each of these trace outliers was in samples mostly on the Eastern Coast of Africa which would have been exposed to Y-DNA T rich Somolians in the sea trade or near the Western boundary of Afro-Asiatic populations that are relatively rich in Y-DNA T.

    But, there are some Cushitic populations with little or no Y-DNA T, so Y-DNA T doesn’t make a good source population for the Cushitic language either.

    While hard data implies that it is possible that Y-DNA T conceivably could have arrived Mesolithic migrants, a narrative in which Y-DNA T is one of the clades present in the first population to bring the Fertile Crescent Neolithic package to Sudan, Ethiopia and Somolia via the Nile makes a lot more sense, even though this compresses the time frame for their arrival to no more than 700 years prior to the R1b-V88 proto-Chadic men. And, it also looks like that Y-DNA T wave, like the Y-DNA R1b-V88 wave, was male dominated, because there aren’t corresponding West Asian/SW Asian mtDNA clades in the places where Y-DNA T is found in Africa of the right time depth.

    There are two main back migrating mtDNA lineages in Afroasiatic language speaking areas: mtDNA M1 and mtDNA U6. But the time depth of these clades in Africa is far too great (well into the Upper Paleolithic) and there are absent pretty much everywhere outside of Africa that Y-DNA T is found. Gonzalez et al. 2007 suggest that Afroasiatic speakers may have dispersed from East Africa carrying the subclades M1a and U6a1 but that would still have been pre-Neolithic, and mtDNA U6 is predominantly in places where Y-DNA T is not found within Africa.

    Another thing that makes Y-DNA T seem more plausible as a Neolithic rather than Mesolithic arrival in Africa is that Y-DNA T is a secondary Y-DNA component (after Y-DNA G) in the first wave Neolithic populations of Europe including ancient DNA from early Neolithic Anatolia and LBK populations in Germany.

    What About The Natufians?

    Of course, we know that the Natufians weren’t the source of the Y-DNA T men in the Nile Basin and East Africa either, as ancient DNA shows them as an overwhelmingly Y-DNA E-Z830 (which is ancestral to E1b1b-M123) population. But, a lot of Afro-Asiatic people do have a lot in common genetically with the Natufians. And, all of the Y-DNA T rich populations are also rich in Y-DNA E1b1b.

    Natufians were present in the Levant before the Neolithic era. They were a Mesolithic people and their Y-DNA was mostly pre-E1b1b. Many of their descendants stayed put into the Neolithic. There also isn’t evidence that people with African mtDNA L3 (xM xN) were ever common in the Levant, even in the Mesolithic. (The Natufians are a very plausible candidate for the proto-Semitic language sub-family speakers.)

    All populations speaking Afro-Asiatic languages except the Chadic language speakers have significant frequencies of E1b1b-M123:

    Cushitic 32–81%
    Egyptian languages 36–60%
    Berber languages 40–91%
    Semitic languages 7–29%
    Omotic languages 50%

    In the case of Cushitic and Egyptian languages, much of the balance is Y-DNA T (which is also found in Semitic people in the Near East and the Jewish diaspora and in Europe, Central Asia, and South Asia).

    A significant balance of the Semitic language speakers today have Y-DNA J1c3, formerly known as “J1e”, and this is actually a more common paternal lineage than E1b1b in most Semitic speaking populations. But, Y-DNA J1 is strongly associated with low land Middle Eastern origins (highland people in the Near East tend to be more Y-DNA J2) and Y-DNA J1c3 apparently spread from the Middle East into today’s Semitic populations after the original dispersion of Afroasiatic (particularly in light of the Natufian ancient DNA).

    There is also linguistic and genetic evidence that Berber languages and Berber ethnogenesis has a fairly shallow time depth (it may be younger than Chadic).

    E1b1b seems to have deep origins in Africa. Y-DNA haplogroup E is the dominant black African haplogroup (excluding Khoisan and Pygmy populations) with E1b1a (particularly associated with West Africa), E1a (particularly in West Africa and Sudan) and E2 (pan African, but especially Eastern and Southern Africa) are particularly common. There have been proposals for Y-DNA haplogroup E as back migrations, but I find them highly implausible.

    Specific E1b1b subhaplogroups have associations with different groups of Afro-Asiatic speakers. E1b1b1b (E-V257) is associated with Berbers. E1b1b1c1 (E-M34) is mostly Semitic. E1b1b1d (E-V6), E1b1b1f (E-V42), E1b1b1g (E-V92), and E1b1b2 (E-V16/E-M281) are all associated with Ethiopia. E1b1b1e* is found in Southern and Eastern Africa. Based upon diversity and phylogeny roots for Y-DNA E1b1b in Ethiopia or the vicinity seem likely.

    All of this suggests that Afro-Asiatic was a language group that expanded no later than the Mesolithic era before agriculture came along and spread beyond Africa into the Levant at its furthest extent, and the data is not a good fit for Y-DNA T men or Y-DNA R1b-V88 men in the Neolithic being the source of either Afro-Asiatic languages in general or Cushitic languages is particular.

    This is pretty impressive. The population of Egypt increased 100 fold with the Neolithic Revolution and there is little doubt that the Neolithic Revolution’s spread from the Levant to Africa had to have at least some demic component. The fact that the indigenous language family rather than the language family of the Neolithic package bearing newcomers managed to remain dominant is remarkable. But, this seems like a more plausible theory than the alternative that Afro-Asiatic languages had a Near Eastern origin which is not a good fit to some of the key facts we know.

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  14. I’m reminded of the Mediterranean like ancient skeletons in the southern Sahara iirc

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  15. Into Africa: the levantine main lineage radiated throughout the world in a series of waves. The latest wave replaced all but a few archaic lineages in Africa, and it is ideologically driven folly to say those archaic lineages are the main branch from which we all descend.

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