The trans-Saharan slave trade – clues from interpolation analyses and high-resolution characterization of mitochondrial DNA lineages

The trans-Saharan slave trade – clues from interpolation analyses and high-resolution characterization of mitochondrial DNA lineages

Background: A proportion of ¼ to ½ of North African female pool is made of typical sub- Saharan lineages, in higher frequencies as geographic proximity to sub-Saharan Africa increases. The Sahara was a strong geographical barrier against gene flow, at least since 5,000  years ago, when desertification affected a larger region, but the Arab trans-Saharan slave trade could have facilitate enormously this migration of lineages. Till now, the genetic consequences of these forced trans-Saharan movements of people have not been ascertained.

Results: The distribution of the main L haplogroups in North Africa clearly reflects the known trans-Saharan slave routes: West is dominated by L1b, L2b, L2c, L2d, L3b and L3d; the Center by L3e and some L3f and L3w; the East by L0a, L3h, L3i, L3x and, in common with the Center, L3f and L3w; while, L2a is almost everywhere. Ages for the haplogroups observed in both sides of the Saharan desert testify the recent origin (holocenic) of these haplogroups in sub-Saharan Africa, claiming a recent introduction in North Africa, further strengthened by the no detection of local expansions.

Conclusions: The interpolation analyses and complete sequencing of present mtDNA sub-Saharan lineages observed in North Africa support the genetic impact of recent trans-Saharan migrations, namely the slave trade initiated by the Arab conquest of North Africa in the seventh century. Sub-Saharan people did not leave traces in the North African maternal gene pool from the time of its settlement, some 40,000 years ago.

I haven’t read the whole paper through yet, but just from reading the bit I put in bold.. I’m sure that a paper on ancient Guanche mtDNA showed an L haplotype or two present which meant they had to be present a few thousand years ago during the colonisation of the Canary islands.

 The majority of lineages (93%) were from West Eurasian origin, being the rest (7%) from sub-Saharan African ascription

And a very ancient age for L6 crossing over into Spain (about 20 kya) from another paper. So I’m going to state emphatically this can’t be correct. Not to mention that the ceramic using Saharan Negroid ’roundhead’ population reached as far as the Acacus mountains (about 10,500 bp) and would have had some contact/gene flow with the coastal Capsians (who were  a near Eastern /Mechtoid mixed people from the cranial studies I’ve seen and the expansion dates of Y chr J1 and H mtDNA). Although  the majority of the L haplotypes in North Africa are due to the slave trade, they can’t ALL be.
Edit:

I read through this this morning. The most interesting bits of the whole pdf for me were…

Clearly, the main component of the West Eurasian lineages was made of possible Iberian
expanded lineages following the post-glacial climate improvement: H1 (12.35%), V (9.88%)
and U5b (1.23%).

I’d debate the 14k age for this given in the paper… but they had to have arrived before the Taforalt people died as the H, HV /V turns up in those 12k old samples..

A few L3 sequences observed in North Africa have older co-ancestry with other sub-Saharan
regions, but as this occurs in the rarer haplogroups (almost restricted to East Africa), most
probably the scenario will change as these become better characterized. This is the case for
one L3x2 sequence observed in Algeria, which shares an older most recent common ancestor
with two Ethiopian, one Israeli and one Kuwait, at 33,165 ± 4,499 years ago, but one
Ethiopian and the Israeli and Kuwait sequences share a younger ancestor at 19,012 ± 4,200.
Also, one Egyptian L3f2b sequence shares an ancestor with a Chadic one at around 24,809 ±
5,935 years ago
. For L3h1a2 haplogroup, one Egyptian and one Lebanese sequences share a
coalescence age of 26,281 ± 6,139 years old. And for L3h1b, with an age of 36,827 ± 3,772
years
, one of the North African sequences (one Tunisian and one Moroccan) has a most recent
common ancestor of 14,766 ± 4,448 years old with a sequence from Guinea Bissau.

I’ve been looking for mtDNA that could have accompanied the M78 out of Africa (arriving in the near east and NW Africa about 22k ago). While M1 obviously fits that date, it’s nice to see that some of the L3 dates aren’t incompatible with the m78;  being found in Natufian areas of Israel and Lebanon. The Israel/Kuwait/Ethiopian L3 may be a back-migrating L haplotype, not incompatible with the return of M1 and U, or another haplotype caught up in the Lower Nubian expansion and fanned out into the same areas as the m78/M1.

So far, the two only complete published samples belonging to haplogroup L3k have a North
African origin, one from Libya and one from Tunisia. This haplogroup has a coalescent age of
around 29,251 ± 6,524 years old

Who/where did that come from?

But the most useful thing in the whole paper are the maps, which give a quick over view of L distribution in Africa. I’ve reworked this one in colour, as the original is a bit hard to make out in places.

One of the interesting patterns I noticed was the (quite possibly superficial) relation to the expansion of non-L haplotypes and L3h in E/SE Africa. Also the hotspot for L3h in Northern Sudan, makes me wonder if it may not have been a travelling companion to the non-African mt DNA’s at some time. Unlike Maju, I’d say this looks like it has an origin on the Nile rather in Ethiopia, as it seems to have a relation to the expansion pattern of the M1/M1a/m78  from Lower Nubia/Egypt.

I’m going to have a dig to see what I can find on L3h now…

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6 responses to “The trans-Saharan slave trade – clues from interpolation analyses and high-resolution characterization of mitochondrial DNA lineages

  1. I have already made a criticism here. The authors show clear prejudice bias (bordering “romantic Orientalism”) and have no issue in reading their own MC estimates, all older than 10 Ka, as “recent” trans-saharan slave trade in the last 1000 years or so.

    The reality is very different. That’s why one has to read the data and, often, ignore the authors’ opinions (aka “conclusions”).

    The distribution maps are interesting anyhow.

    • The distribution maps are interesting anyhow.

      I saved them to my computer. One of the most interesting things I noted upon reading the paper was the dates for the L haplotypes that could match my ‘Nubian’ expansion circa 24k ago..

      Ethiopian and the Israeli and Kuwait sequences share a younger ancestor at 19,012 ± 4,200.
      Also, one Egyptian L3f2b sequence shares an ancestor with a Chadic one at around 24,809 ±
      5,935 years ago. For L3h1a2 haplogroup, one Egyptian and one Lebanese sequences share a
      coalescence age of 26,281 ± 6,139 years old

      I was an issue that I couldn’t find mtdna trace to match the Ych E moving OOA about 22k ago. problem solved /\

      I have already made a criticism

      Yep. I read it and I agreed. After I posted this I saw you’d made the same comment about the Guanche mtDNA that I did. Great minds think alike…

  2. sorry to disappointed ur Views some Archeological Evidence don’t share with u any Phylogenetic theories about that

    http://s1.zetaboards.com/anthroscape/topic/3212204/1/

    • FRom the link…Actually the Capsian is not of Kenyan origin- the crania studies and dating on the arrival of DNA from the NE place it as a Eurasian back migration. Don’t take that stuff on that page as gospel, a lot is outdated.

  3. Eburran is a term used for the hunter–gatherers in highlands of East Africa. The Mediterranean Caucasoid element which East Africans are mixed with is the local Berberid(aka Atlanto-Mediterranean).
    Kenya Capsian (Proto-capsian) or Eburrians of Kenya which dates between 13,000 and 9,000 BC in East Africa were of Mechtoid Ouchatian stocks origins sometime named for Aurignacians
    http://carnby.altervista.org/troe/02-09.htm

    in the Holocene Era the environment of the Maghreb was open savanna to East Africa there was an ancient Movements of Mechtoids and Archaic Mechtoids from North Africa to East africa plus there is two different Major capsian of pre-Neolithic era :
    Upper Capsian and Typical capsian
    that’s if you want to understand from where the ethiopians and Nilo-saharans get these Oldest Haplotypes
    http://s1.zetaboards.com/anthroscape/topic/3195550/1/
    No one said that capsian is of Kenyan origins ,big difference between a pre-capsian culture (Kenya) and a modern capsian culture (North africa) wich is due to similarities in the stone blade shapes.
    http://en.wikipedia.org/wiki/Capsian_culture

    • in the Holocene Era the environment of the Maghreb was open savanna to East Africa there was an ancient Movements of Mechtoids and Archaic Mechtoids from North Africa to East africa

      Not that I’m aware of. The Mechtoids originated in the Nubia area about 24k ago, related microlithic stone tool cutlure known from the Wadi Halfa area that turns up in Israel as the Kebaran and North Africa as the IM culture. The same population expanded from Nubia into East Africa.

      The upper and tpyical Capsian are just chronologically seperated but from the same origin. There’s no connection to the Eburran at all in any way. There’s a DNA trail leading back to the middle East, and a common snail eating culture to the Levantine Med coast with North African Capsians about 10k ago.

      The Mediterranean Caucasoid element which East Africans are mixed with is the local Berberid(aka Atlanto-Mediterranean).

      Well no it isn’t. East Africans are very short on Berber ancestry. Virtually Nil, in fact. Their Caucasoid ancestry only ever traces back to the East (via Nile or over the Red sea), never to the North West.

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