Is this mysterious Arabian hunter-gatherer discussed before?
When did you think Natufians expanded to other regions such as Mesopotamia and/or North Africa? Or perhaps it was just like tariq moses and you suggested there was no significant migration but a metapopulation sort of existed in the three regions?
Last, how about the Marsh Arabs? Also, your proposal about modern Iraqi minorities seems quite logical, as the entire Mesopotamia was basically a place featuring populations with hooked noses and prominent beards fighting and "marrying" each other. Kind of weird to think they would only trace ancestry to one particular group of a certain period, IMO.
Btw, that's a very informative answer as always.
I have no idea if they did, to be honest. There is a semi-strong case for hunter-gatherer Levantine to have penetrated relatively deep into the Arabian Peninsula, furthermore, Arabian hunter-gatherer migration is not new to the people that talk about this subject. The lack of ancient/pre-historic sampling is important to emphasize. What I wrote about Mesopotamia with the other hypothesis is merely a conjecture.
I don't know what the meta-population entails -- I don't know if it makes intuitive sense for me conceptually. In this case, I might make a simple model talking in the sense of split/migration/divergence from a bunch of information we know, trying to not make it too formulaic or rigid of a proposition to the point where it can't be flexible (room for combinatory arrangements). Or in contrast, make something too flexible that it doesn't have predictive value or doesn't reflect reality. Oversimplified models are good if you can calibrate and try to approximate the true picture while grasping the weakness. The reality is, there is no such thing as Dzudzuana as one single broad thing; it's only a complex pre-LGM genetic variety that we lack the full resolution of which we consider as one thing because several divergent yet ancestrally related groups have a relative affinity for it. For example, the Taforalt West Asian ancestry is not from Georgia, nor is the Dzudzuana (the real sample) originally from that part of the world either, strictly speaking about the nexus radiation point geographic disposition.
I don't think Natufians expanded to North Africa. The inverse is the case for a lot of its ancestry. We know that Natufian received ancestry that seemed endemic to northwest Africa in the high twentieth percentile, but it could trace much more ancestry in total from North Africa because the diversity is not limited to Taforalt (there was a gradient with decreasing Taforalt ancestry as you moved from west to east of North Africa). Northeast Africa already had something similar to the terminal Paleolithic Levant populations, so thinking that a population that had way more enriched ancestral Near Eastern component (Dzudzuana-like) migrated into the Levant, additionally mixing with a complete Dzudzuana-like ancestral population in the Levant but which had small population size, then, being charitable, Natufians might derive higher than presumed northeast African derived ancestry that settled in the Levant from Egypt (with a two-wave model, one from northwest migrating, absorbing some ancestry in Egypt or frontier Libya, another wave to later arrive in the Levant through the Sinai), than a model that states that it was a population that received some substantial minor pure Iberomaurusian related component. I think there is an archeological precedent because I think the Natufian culture is related to a North African culture that moved into the Levant. Those culture carriers are strong contenders for potentially harboring significant of the Natufian DNA compositions and then later mixed with a less African-like population in the Levant that had a smaller population density, so they got absorbed. However, it can be that the proto-Near Eastern (Dzudzuana-like) population in the Southern Levant was indeed more numerous so, and that will change the geneflow amounts a bit and depreciate the North African side, consequently meaning the North African peoples had a bit more Iberomarusian concentration than the first hypothesis of this paragraph tries to illustrate. The central point is, the sequence of events can be complex when you deal with so many moving parts across time.
In some admixture models, the Near Eastern ancestry in Taforalt and Natufians seem closer in terms of divergence point, while ours, the Cushitic seem to have split a bit before the Taforalt and Natufians. The question is, assuming if these models are correct on the surface oversimplification, did the Cushitic Near Eastern component split off earlier, entailing that it existed in Egypt or Sudan while a true Iberomaursian-like people migrated to the Levant, not interacting with the Cushitic hunter-gatherer ancestors? If that happened, does that mean, that potentially, the Cushitic ancestral lived further down into Sudan or just south enough in Egypt for them to not genetically interact? Another thing can be that the Cushitic ancestry got some agricultural Levantine ancestry admixture which got some Anatolian Neolithic Farmer component that can bias the admixture but to be honest, I don’t know to what degree this would affect the scale. Either way, these three somewhat bifurcated (including the one from Georgia), or at least, geographically separate demographic historical pictures trace coetaneous origin somewhere before the Late Glacial Maximum.
The Upper Nubian Epipaleolithic sample Al-Khiday, and conceivably other hunter-gatherer samples in the late Paleolithic context in Egypt, if sequenced, can give us a better picture to infer more robust explanatory power of other related, not directly attested data as well, that has broad significance beyond its scope.
Putting beards and noses to the side, Marsh Arabs can be similar to the general south Iraqis. Given the lack of comprehensive data on account of sampling scarcity, we still got two samples derived from the marshlands. The samples indicate a general Iraqi profile with high-middle Arabian input, middle-high Iranian_N component, and slightly higher Anatolian farmer relative to the complete Iraqi sample set (that includes non-Arabs). Speculatively speaking, higher frequency of Peninsular Arabian ancestry in southern Iraq can give room for partial if not substantial genetic geneflow toward the marshland Iraqi people, given the tremendous south-north influence Arabs had on the region attributed to regional dominance of Islam. Even back in the late Mesopotamian era, various Arab tribes, particularly the Nabateans, were well attested. I am not aware if the Arabs in the marshlands have their sub-ethnic endogamy, ways of life that insulate them from receiving similar or symmetrical differential gene flow of ancestry from the south than the general Iraqi demography besides religious sectarianism.
At this point, such south-to-north genetic exchange I reckon has stabilized. Besides the known Arab tribes that trace their family origin to the Peninsular (I bet the overwhelming majority claim Arab origin from a tribal perspective), I am reluctant to draw total relative regionalism. You can find presumed 'Mesopotamian' profiles in the south and encounter heavy Arab admixture further north. The northernmost frontier, I suspect another matter. Iraq is genetically complex, and truth be told, the few Marsh Arab samples veer not outside the genetic broader diversity (I think they are nested well within it), and they did not seem, at least, recently admixed with Arabian, that's not to say that possible multiple thin layering sweeps can have happened throughout history given the dynamism of the region. The early Sumerians are said to have originated in the marshlands south. The Marsh Arabs can be fluctuating similarly for all we know like the general Iraqis since these samples might be representative only aspects of the broader cluster. How much direct continuity of the current genetic profile average goes back to the late Chalcolithic is a challenging question to answer. I know little about these particular people. This
link might help a bit.
