Mozabites in an unsupervised ADMIXTURE analysis are generally modal for their own component, which then dominates fellow North Africans, and is present in small amounts in some East Mediterranean populations with no likely contact with Northwest Africa (its presence in Iberians has likely other reasons explored later). Under a theory of Neolithic Replacement, this doesn't make sense, since North Africans are agricultural peoples since ancient times...
Thus I decided to try to break them up into Neolithic source components using the supervised mode in ADMIXTURE.
Three likely sources of Neolithic techs and genes are present in the region:
1. Northern Fertile Crescent: In order to distinguish a first wave from secondary waves from other regions in the Fertile Crescent area, I decided to use Basques as a pole. In retrospect maybe Basques absorbed some small but not insignificant secondary wave component too, but since it was likely much less important than in North Africa and the Middle East, the choice is still valid (may have to use populations from further North as a first wave pole next time though).
2. Northeast Africa: Egypt is obviously a major candidate for a secondary "Southern Fertile Crescent" wave. Their fast appearing shining civilization indicates extra surplus food production allowing exceptionally large elites. Surplus food techs would likely expand along with the people using them, since they would allow for higher densities of agriculturalists versus less advanced "first wave"-tech using peoples. However it's expected that secondary wave people (but not techs or seeds) will travel much less far than first wave ones, since already agricultural peoples will effectively resist and learn since they share a similar mindset already.
A complication to use Egypt as a pole is that Egypt very likely received high genetic flow from the Northern Fertile Crescent as it was perhaps a more peripheral but integral part of the West Eurasian Neolithic Core Area from the start of the Revolution. Thing is, Egyptians also have very significant non-Western Asian components they share with other East-Africans, namely Ethiopians and Maasai. Since Ethiopians also seem to have received major influence from the Arabian Peninsula in ancient times, a more southern pole must be sought to make things clearer with less overlapping. If North African populations have East African components, we can use Egyptians directly later, but in this analysis I chose the Maasai.
3. Western Africa: Western Africa's Neolithic Revolution seems to have happened later than the Fertile Crescent one (which failed to expand into the region due to seed-package maladaptation to tropical conditions). Still, there was likely much gene flow between both regions so I included them as the third pole (Yoruba+Mandenka).
Here are the results:
A possible interpretation: Mozabites may be a compound of an earlier Southeastern-subset Fertile Crescent Egyptian wave superimposed by a dominant more advanced Northern-subset Fertile Crescent one. As seeds, cultural practices and genes mixed in the Nile, a second (or third for North Africa) Fertile Crescent wave would expand and Egyptian Civilization would arise in the Nile itselfit.
It's interesting that populations from more arid areas have more "West African" (Mozabites themselves, Libyans, South Moroccans). It may seem more likely that the West-African minor component is derived from later expansion of West Africans and the caravan trade. However little is known, as far as I'm aware of local Forager genetics since no forager populations remain in North Africa today. Foragers likely remained in regions not congenial to agriculture until development of desert Pastoralist (camels, goats) lifestyles in Arabia much later. One tantalizing possibility is that it was more West African-like from the very beginning. The Saharan pump theory may offer some clues, since the Sahara during the Ice Age was much more congenial to (forager) gene flow from the south than today...
The model predicts this "Egyptian wave" would spread to Europe and the more distant Near East using the obvious expansion routes already travelled by first waves. It would however petter out relatively quickly as Egyptian colonists failed to completely overwhelm numerically already neolithic first wave peoples and would become more "first-wave-like" genetically the further one travels from Egypt. I will analyse European populations for evidence of Egyptian/East African admixture next.