Holocene human peopling of Libyan Sahara

Holocene human peopling of Libyan Sahara – Molecular analysis of maternal lineages in ancient and extant populations of Fezzan

The present work provides an important view of a region of Africa that is still almost unknown: the Central Sahara. The aim of the project as a whole, was to reconstruct from the maternal side, through the genetic analysis of mitochondrial DNA (mtDNA), the origins of a Pastoral nomad population in the Libyan Sahara, the Tuareg. The availability of both modern and ancient samples from the Fezzan (Libyan Sahara), collected in collaboration with the Italian Archaeological Mission in Libya directed by Prof. Savino Di Lernia, represented an important means of relating the mtDNA pool of extant Libyan Tuareg, with that of Pastoral people inhabiting the Central Sahara in prehistoric times, and with the Garamantes, the hypothetical ancestors of Libyan Tuareg. Nevertheless, molecular analysis carried out on the bones collected from the archaeological sites of the Acacus region, showed a very low state of preservation of the DNA, this probably due to the high temperatures that characterised burials over the centuries. Failure of the genetic analyses in the ancient individuals, necessarily limited the present work to the study of the extant Tuareg sample. Nevertheless, comparison with other genetic data collected so far in the modern African populations, and moreover the multidisciplinary integration with archaeological and ethnological data, helped to hypothetically reconstruct the origins of Libyan Tuareg, and their relationship with the ancient human migratory dynamics that occurred in Northern Africa during the Holocene.

A total of 129 individuals from two villages in the Acacus region, in Fezzan, were genetically analysed at the mtDNA level. The results here reported clearly show the low level of genetic diversity in the Libyan Tuareg sample, that is hypothetically due to high endogamy. Furthermore, phylogenetic analyses indicate that the mtDNA genetic pool of the Libyan Tuareg is characterized by a major “West- Eurasian” component, that is shared with many Berber groups and hypothetically comes from the Iberian Peninsula, and a minor “South-Saharan” component that shows some kind of  relationship with Central and Eastern African populations.

A pdf I located with a lot of information on North Africa and The Tuareg, for anyone interested in their history and culture and maternal ancestry.

tmap

The pdf book (it’s very long) shows H1 to be dominant in the Tuareg sample tested at  frequencies higher than 60%, H1 having roughly an 11,000 year old presence in North Africa. Eurasian lines H and V  make up nearly 2/3 of Libyan Tuareg mtDNA. This paper also finds traces of Eastern African ancestry in the Tuareg via the L2a lineage which has a coalescence date of around 5,000 years, which is tolerably close to the theorised Beja/Tuareg split of 6,000 years. It’s got a pretty detailed breakdown all all the Hg’s found.

Luis, you’ll like this one. Places the U in N Africa as Iberian in origin.

7 responses to “Holocene human peopling of Libyan Sahara

  1. Luis, you’ll like this one. Places the U in N Africa as Iberian in origin.

    Hmm… I have just been able to make a “quick” (several hrs.) reading of such a long paper but I understand that they mention the Iberian origin mostly in relation with H, H1 and V lineages. U6 seems petty minor among the sampled Lybian Tuaregs and is not (I beleive) separately analyzed.

    Instead H1 is very dominant, especialy what they call the H-CRS, which is in fact not H2a but H1 with the CRS haplotype for the HVS-I sector. I am wondering now if the finding of “CRS” in Paglici Cave’s aDNA actually means just that: a CRS-like haplotype and not the full CRS sequence that certainly belongs to H2a. If so it would be H almost for sure but would solve the inconsistency of being a fully derived modern haplogroup (in the original discussion at Dienekes someone said it should be HV but not sure if he was right). I’ll have to re-read the paper to find out.

    Actually, I am reconsidering somewhat my position re. U6 origins. I was re-reading the relevant paper of Maca-Meyer and the highest haplogroup diversity seems to be in fact not in Iberia but in Morocco. U6c, the rarest of all major U6 haplogroups, is almost exclusive of Moroccans and Canarians (central node in Morocco). This would place U6 urheimat in North West Africa and its presence in Iberia could mean, IMO, an ancient exchange at the Iberomaurusian genesis. This would have implied major migration from Iberia to North Africa, signified by haplogroups H (H1 and H3 especially) and probably V as well, but also some backflow from North Africa, represented by U6* and U6b and maybe even Y-DNA E1b1b. Alternatively, U6b and E1b1b could have arrived to Iberia in the Neolithic (though U(xU5) was detected in Epipaleolithic Portuguese and I suspect it should be U6).

    Whatever the case, a NE African/West Asian coalescence for U6 is most unlikely, as these regions just do not have enough diversity to sustain Maca-Meyer’s conclussion. In fact I don’t find even clear evidence to support a NE African coalescence for U6a alone (the core of MM’s hypothesis), as the main node is best represented (by large) in Algerian Berbers and most of the rest are either NW African or Iberian people.

    Hence my current standing is that U6 is a NW African founder effect (derived of course from an original West/South Asian U) that expanded to Iberia (U6*, U6a, U6b) and NE Africa/West Asia (U6*, U6a) within the context of IM genesis, and has a clade that remained locally constrained to Atlantic North Africa (U6c). What early UP culture could represent these pre-IM North Africans is something I still don’t know though.

    Whatever the case, it is H (and possibly V too) which clearly evidences a flow from Western Europe (probably Iberia) into North Africa. This flow is IMO best explained by the Iberomaurusian (Oranian) genesis.

  2. Btw, I found a general reference to some “Aurignacoid” North African culture, the Dabban industries or something like that, in relation to U6 expansion into North Africa. This industry, I understood, would be the parallel (not derived) of European Aurignacian south of the Mediterranean, both being derived from a common Levantine source.

    I was wondering if you have ever stumbled upon this technocomplex, that would fill the blank between Aterian and Oranian – or at least imply older than Oranian human presence in North Africa that would be at the origin of U6. The reference for this association is Olivieri 2006 but it’s behind a paywall.

    • Funny, I just responded to a comment on that a few minutes ago (sorry for the tardy response, my kids and husband get my attention at the weekend).

      Dabban industries appear about 42k ago in N Africa. I’ll see what I can unearth this week. It was a microlithic culture.
      Here’s a quick link for it. I’ll blog it later..
      http://www.paleoanthro.org/dissertations/Colin%20Moyer-abstract.pdf
      The Organisation of Lithic Technology in the Middle and Early Upper Palaeolithic Industries at the Haua Fteah, Libya.

  3. “Luis, you’ll like this one. Places the U in N Africa as Iberian in origin.”

    Well, correct me if I’m wrong but isn’t the highest diversity of U6 in Spain (indicating its probable location of origin) ?

    • PM
      Yes, but…Maca Mayer places it’s expansion from Asia- and to be honest I’m just not the sort to disagree with a published professional without a sterling reason.

      Also, I’m not sure modern humans made it into Iberia early enough to make the est expansion dates into NW Africa, and because it seems to track in with M1 (Mt)and R1 (Y), which definitely didn’t come from Iberia. There seems to be a population replacement going on in NA during the Aterian that was simulatneous with the displacement of the Neanderthals.. the Dabban industry appears about the same time (42K) with microliths and there’s a transition away from older stone tool techniques in NA. Modern humans don’t arrive in Iberia until after this (about 5k plus).

      .

  4. Dabban industries appear about 42k ago in N Africa. I’ll see what I can unearth this week. It was a microlithic culture.

    Thanks for the link, very much appreciated. I wonder if they have been found west of Lybia.

    Anyhow, I don’t understand they were “microlithic” at all. Not just it is too old for that but also the few descriptions I have seen don’t fit with that at all. The link you just posted says: “Unlike the previous periods, the Early Dabban
    shows an integration of these conceptual modes in a single, numerically abundant
    technology (blades)”.

    Here there is another link I found (after posting the previous comment), which analyzes Dabban industries, which seem fully typical UP, distinct from typical European Aurignacian but guess relatedness can be argued, as happen with a number of West and Central Asian industries of that time. Chronology is also very much Aurignacian-like.

  5. Well, correct me if I’m wrong but isn’t the highest diversity of U6 in Spain (indicating its probable location of origin) ?.

    I first thought that from the text at Maca-Meyer’s paper but looking at the actual data, the highest top-level diversity is in fact in Morocco (because it includes the rare lineage U6c, absent elsewhere) and the highest overall diversity probably in Canary Islands, though it is derived from the Moroccan (and secondarily Iberian) pool.

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