As I implied previously, several components in my previous run bear no close similarity to their respective poles. Just as when you run World populations with an African population pole and a (northerly) Eurasian one you can see "Out-of-Africa"; and when you run these with Papuans as a 3rd pole the Coastal Migration remains; by choosing appropriate forager poles you can maybe see the other hidden "foragers", including those that underwent massive expansion during Neolithic Revolutions.
Assuming that the method is valid, and I think the results are sufficiently reasonable according to other sources of data to believe there is at least more validity in it versus unsupervised ADMIXTURE runs, several reasonable interpretations can be made. Validity does not mean that the results of the run are the objective ultimate reality only that they're perhaps a better model of what happened 10.000 years ago and since, than previous ones.
My personal interpretation of the data.
1. "Chukchi" is really about a massive demographic expansion that can only be explained by a Neolithic Revolution. Does not imply close relationship to actual Chukchis from Far-Eastern Siberia, although this may have been the best "Childless pole" available in the sample fed into ADMIXTURE in this run. Siberia might have been populated after the Ice Age by a less distantly related population. I think it's likely this corresponds to the original Mesopotamian Neolithic Core population.
2. "!kung" same caveats apply. I believe this may correspond to a secondary Fertile Crescent Core in the Nile Valley and its radiation, developing within the influence but also largely independently from the Mesopotamian Core, in an endless tug-of-war. This component would correspond roughly to a Northeast African forager population successfully adopting agriculture.
3. "San" I think it's straightforward that this is about ancient Eurasian Forager populations. Perhaps more related between themselves than to the Mesopotamians or Siberians, and also perhaps somewhat closer to both actual !kung and San than to Siberians?, even though still very distantly related to either. It was perhaps more expected for a Siberian-like population to be present in Paleolithic Europe... I will be digging further into this if I'm able. Still, it's not impossible that an earlier diverging branch of modern Humans existed in the region prior to agriculture. This could correspond to both an Iberian refugium population expanding North after the Ice Age and relic populations in the Caucasus mountain range area (mountain populations being frequently less afected by demographic shifts). There has been some debate between Anthropologists about differences between early Paleolithic West Eurasians. I frankly don't think the results presented here, allow for anything to be presumed at this point.
Anyway, this population doesn't exist anymore as it existed then, but maybe enough recognizable fragments exist in some of us for someone eventually to reconstruct it?
4. Nganassan: probably simply very Nganassan-like ancient forager Eurasian populations. Nganassans are among the most westerly Siberians.
5. Koryak: same as Nganassan
6. Evenki: also very Evenki-like population, interestingly it can be found in small amounts in Turks as might be expected.
7. "Maasai": contemporary Maasais are actually significantly affected by other populations, still I believe this was a good match to ancient Forager populations living nearby ancient Nile River valley ones. May correspond to large components in ancient Nubians, for instance. Might it also be associated with Nilo-Saharan languages and pastoralism? They might be the Eastern branch of the Green Sahara populations (the Western being perhaps part of the Yoruba-like component in North Africans and Fulani), thrown East and South by the desertification process.
8. Yoruba: in this context representing the West African Neolithic and perhaps also more anciently related Green Saharan populations converting to pastoralism.
9. Hadza: This pole picked up sufficiently numerous small segments in neighbouring populations, so ADMIXTURE wasn't forced to "marry it" to more distant segments. Not a very relevant component in this context.
10. Mbuti Pygmy: same as Hadza.
So here's the model I think most likely with the current data. I'll review it if necessary:
1.Iberia and the Caucasus mountains inhabited by Forager A populations, who expanded to Northwest Europe after the end of the Ice Age. To the east of Mesopotamia the Coastal Migration peoples. In Northern Eurasia distantly Mesopotamian related? Siberian-like forager peoples (I didn't include East Asians in the run, so ancient Mesopotamians might just be the closest population here, even though still quite distant). In Northwest Africa West African-like forager people.
2. Mesopotamians evolve Neolithic attributes, then explode demographically all over Western Eurasia, replacing Forager A and Western Siberian-like and Coastal Migration peoples.
2. Nile River Valley people also develop Neolithic capabilities, but in a less effective way at first. They expand into North Africa, Ethiopia and the Green Sahara, largely replacing previous West-African-like and Maasai-like peoples.
3. Mesopotamians clash with Nile Valley people, replacing them partially as the dominant genetic element in the Nile itself.
4. A new synthesis between both populations arises in the Nile River, establishing the foundations for the later development of Egyptian Civilization and leading to a second wave (third for Nile Valley influenced North Africa, Nubia and Ethiopia) that has a major demographic impact in the Near East, Mediterranean-Atlantic region and the Balkans. Mesopotamians in peripheral regions absorb the most important parts of this new Neolithic package just in time to avoid major demographic shifts.