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…

Taforalt man into the Sahara.

L’homme de Taforalt au Sahara, ou le problème de l’extension saharienne des Cromagnoïdes du Maghreb

The important discovery of a cro Magnon settlement in the Southernmost Sahara  dating to the Holocene brings new data on the morphological and geographical evolution of the Cro Magnon population of the Maghreb (Men of Mechta-Afalou-Taforalt). The great resemblance between the men of Taforalt and those of the Sahara (Hassi-el-Abiod, Mali) pose the problem of their origins. Was it a migration from the Maghreb at the beginning of the Holocence aided by favourable climate conditions or regional evolution from the regional Aterien stock mixing with the Cro Magnons of the Maghreb and the Sahara? The numerous climatic changes occurring in this part of the Sahara during the last 30,000 years could be an efficient evolutive promoter and can explain the morpholgical and cultural differences observed between the Sahara and Maghrebian series. However, what will happen later to African Cro magnids in the Maghreb and especially in the Sahara is still an open question.

 I’m not going to translate the whole thing, but it observes that the Mechtoids vanish about 7,0oo years ago (very latest site in the Sahara, but they are gone by 10,000 Bp at the coast when the Capsian culture arrives from the near east) when the proto- mediterranoids arrive, and they are not found in later sites. When I have a little more time I’ll make up a more comprehensive entry involving this and the other work on mechtoid populations and genetics that should explain their origins and relationships a bit more clearly. Please excuse my imperfect translation.

Conclusion

These new discoveries bring three new basic concepts; firstly, African Cro Magnids occupied a vast part of the North of  Africa of the end of Pleistocene until  the beginning of  the Holocene; secondly in spite of regional morphological characteristics, all Mechtoids belong to the same group; thirdly these facts suggest the existence of a common ancestor to these three populations and this ancestor could be represented, until there are other older discoveries, by the Aterian people.

Which I’d have to disagree with, as the stone tool cultures and genetics suggest an expansion from Lower Nubia/Egypt about 24k ago that spawned off the Mechtoid/Kebaran populations, which was roughly equal in terms of back-migrating Eurasian and Nubian-African ancestry. Except for the Taforalt population, which ADNA has shown was entirely Eurasian for mt DNA, and may have been the result of a migration southwards across the straits of Gibraltar about the time of the LGM (20k ago) mixing with the local Mechtoids.

Guanche Y chromosomes

Demographic history of Canary Islands male gene-pool: replacement of native lineages by European

Abstract
 The origin and prevalence of the prehispanic settlers of the Canary Islands has attracted great multidisciplinary interest. However, direct ancient DNA genetic studies on indigenous and historical 17th-18th century remains, using mitochondrial DNA as a female marker, have only recently been possible. In the present work, the analysis of Ychromosome polymorphisms in the same samples, has shed light on the way the European colonization affected male and female Canary Island indigenous genetic pools, from the conquest to present-day times.

Results
Autochthonous (E-M81) and prominent (E-M78 and J-M267) Berber Y-chromosome lineages were detected in the indigenous remains, confirming a North West African origin for their ancestors which confirms previous mitochondrial DNA results. However, in contrast with their female lineages, which have survived in the present-day population since the conquest with only a moderate decline, the male indigenous lineages have dropped constantly being substituted by European lineages. Male and  female sub-Saharan African genetic inputs were also detected in the Canary population, but their frequencies were higher during the 17th-18th centuries than today.

Conclusions
The European colonization of the Canary Islands introduced a strong sex-biased change in the indigenous population in such a way that indigenous female lineages survived in the extant population in a significantly higher proportion than their male counterparts.

Unashamedly nicked from Maju- but topped off with a genuine portrait of a Guanche male called Hairy Harry (centre) shown to me by Ricardo.

Interesting to see the J1, which a couple of studies have placed in North Africa from about 10k ago. A fair amount of other older Eurasian lines. I’ll have another read of this one later.

Y chromosome J’s tangled past in Africa.

Just something I’ve done to help me get a better grip of the history of the Y chromosome’s presence in North Africa. Firstly, I need the J tree and it’s distribution from Cruciani 2004.

And some more detailed information on the distribution in the places relevant. Most important to this are J-m267 /J1, (typical of Arabs and common in East Africa) and J-m172/ J2, (which maps the expansion of the Neolithic into Europe and apparently into Pakistan (J2e) and North Africa).

J1 is typically seen as the marker for the Arab tribes expanding into North Africa, and this accounts for somewhat more than half of the J in North Africa. However, the J1 in East Africa is lacking a alteration in the historical-Arab specific Y chromosomes, and the latest paper I have seen dates the entry of this to Africa at the Iberomaurusian-Capsian- (pre neolithic) transition-or possibly a little later- which would require an entry date about  of about 12k ago.

Cruciani’s Bedouin sample was free of  J2 – as you can see from the maps there seems to be a break in it’s distribution pattern. A look at Italy and Greece (looking for other possible source of J possibly from the Romans and Greeks) showed it at levels low enough that for the Greek and Romans to have made any impact on the J Y chr of North Africa they would had to have left way more European specific haplotypes (the highest J observed in Italy is 29%, overall it’s a lot lower) and the same is true for other middle Eastern countries- to have added any extra J2 into North Africa a lot of other non-J Y chromosomes would have to have accompanied it. The North African Y chromosomes (Lower Egypt as the prime example)  just aren’t that varied and mainly show ‘ancient in Africa’ Eurasian and African specific Y chromosomes, with J making up most of the difference, which makes Europe and the recent near East as a source for the J2 unlikely. 

The distribution of J2 and J1 in North and East Africa, and whatever near Arabian populations I can find.

From Cruciani 2004

Egyptian

From Luis 2004 in Lower Egypt and Oman.

• Egyptian Arabs… J1 20%   J2 12%
• Oman Arabs…..    J1  38%   J2 10%

From Lucotte 2003

• Lower Egypt…. J1  10.5%  J2  8.6%
• Upper Egypt….  J1  3%        J2  4.5%

From Arredi 2004

• Lower Egypt… J1  9%,  J2 9%
• Upper Egypt     J1  21% J2 3.5%

I’m omitting the other studies I have on file as they don’t differentiate between the two, or lack clarity on which is which.

As the other studies are either a bit vague or very small I stick to these. The average amount of J for lower Egypt seems to be 25% (average of 5 studies) with about 10% being J2. Bearing in mind about 10% of the North African J1` is pre Neolithic, about 13.5% of the Egyptian Y chr are ‘Arab’ J1-possibly. J2 from the recent Arab expansion into North Africa probably does contribute to the J2 in NE Africa, but not in the main. The argument against this is that J2 is a minority in the Palestinian Arabs and Bedoiuns , and that to get J2 up to the levels you find in Egypt you’d need to have a lot more J1 and other Eurasian male ancestry- which would make the other African/ancient EurAfrican types way less more common. J2 is also common in Persia (who also invaded Egypt), but again it isn’t dominant and you would have to expect large amounts of other Y chromosomes to have accompanied it, which has not been observed (same argument against a European origin for Egyptian J2).

If the J2 had come in with the Arabs you’d expect a very obvious overweight of J1 in the ratio-as in the Sudan. It’s not even clear if the J1 there is all ‘Arab’ in origin, as the most of the J1 in East Africa is the pre Arabic J1- which makes Hassan’s 2008 choice of description as ‘Arabic’ for all the J1 in the Sudan a little confusing. As Cruciani wrote..

According to this interpretation, the first migration, probably in Neolithic times, brought J-M267 to Ethiopia

Although, I have to say; Hassan’s calling the Sudan Copts a living record of the Egyptians is strange considering how low they were on African Y chromosomes- particularly the Egyptian m78; and that 13 of 33 samples were J1.

While large scale historic movement of Arabic tribes into the Sudan is well documented, a lot of J1 is showing up in groups like the Nubians. When you bear in mind Arab culture is very patriarchal, I can’t understand how the non-Arab groups in the Sudan seem to have about the same amount of J1 as the Arab tribes in the Hassan study. Did more Arabs move into the Sudan than North Africa or is the recent and ancient J1 just getting lumped together in these studies?

I’m sure I’ll add to this post after my regulars have corrected/added whatever info they feel is necessary, but I think mainly but not entirely the J2 in North East Africa is a result of the Neolithic expansion, as it does seem to form a neat radial pattern from Turkey/Iran which is seems to track along with the R1b/p25, which also seems to be Turkish/Iranian.

Delayed Use of Food Resources among Early Holocene Foragers of the Libyan Sahara

Dismantling Dung: Delayed Use of Food Resources among Early Holocene Foragers of the Libyan Sahara

At Uan Afuda, and other Early Holocene sites of the Acacus mountains, in the Libyan Sahara, dung layers and plant accumulation are a major, but repeatedly neglected, feature of hunter-gatherer communities. To understand the formation and meaning of such features, a multidimensional analysis has been undertaken, combining micromorphological, palynological, botanical, archaeozoological, and archaeological data. The hypothesis here formulated is twofold: plant accumulations are evidence of anthropic activity aimed at the storage of fodder; and dung layers are related to a forced penning of a ruminant, very likely Barbary sheep (Ammotragus lervia). The exploration of these two features has hinted at the existence of a deep reciprocal relationship, which has been interpreted as the cultural control of wild Barbary sheep, leading to a delayed use of food resources. This behavior may be considered an opportunistic strategy adopted to minimize the effects of lean periods and implicates increasing cultural complexity within Late Acacus Saharan forager societies of the 9th millennium B.P.

Studying the ‘management’ of Barbary sheep (a kind of gazelle related to sheep and goats) during the Holocene. The paper points out a few flaws with Ehrets use of the terms ‘to drive’ etc in proto Northern Sudanic…

Of interest here is the evidence that the first forms of a planned or delayed use of resources in NorthAfrica were initially directed toward animal rather than plant resources. As a matter of fact, with the Proto-Northern-Sudanic, the roots dedicated to the vegetal world are grains and grindstones, not necessarily implicating either a delayed use of resources, or a possible incipient domestication. Conversely, with regard to the animal universe, the root “to drive” may be referred to a kind of hunting or also other activities. Since examples of hunting performed by means of fences are not known in North Africa, the idea that the root may be related to the driving of animals in specific areas (corrals?) appears to be appropriate. Finally, the root “to milk” is also linked to a typical secondary exploitation, as may be seen in the case of Bos exploitation at Bir Kiseiba in the eastern Sahara.

So I’m not the only person who spotted it. The fact that captured wild animals were being ‘kept’ in the Sahara not that far away from Nabta in space and time does have a bearing on the suggested cattle domestication there. A similar scenario to the Barbary sheep would seem more likely, as physically distinguishable domesticated cattle only appear along with Neolithic Asian goats and sheep, and don’t show an closer point of origin like Nabta with dates for domesticated cattle radiating out from the area (fully domesticated cattle should have been seen from dates as old as 8,300 bp in Egypt and Nubia if that were the case- but they aren’t). It would be interesting to look at the bone isotope values of pre-domestication sites in both Asia and north Africa to see it they were using dairy from tamed animals.

Recognizing population displacements and replacements in prehistory: A view from North Africa

Recognizing population displacements and replacements in prehistory: A view from North Africa

C.M. Stojanowski. Center for Bioarchaeological Research, School of Human Evolution and Social Change, Arizona State University.

Bioanthropologists use skeletal data to reconstruct the historical global distribution of humans. One of the more critical and contentious issues is the inference that a complete population replacement has occurred which has importance for our understanding of human biological variation as well as issues of cultural patrimony. Despite the ubiquity of such analyses, problems exist with current methods because the degree of phenotypic change through time is dependent on demographic parameters, processes of selection, and changes in subsistence orientation which reflect the malleability of cranial form. How different do two populations need to be for continuity to be rejected? In this paper the population history of northwestern African and central Saharan populations is discussed from the Late Pleistocene through Early Holocene. Craniometric data are used from nine chrono-spatial samples to address the relationship between temporally sequential populations in North Africa where long term changes in aridity prevented human occupation for several distinct intervals. R matrix analysis resolves several perceived population discontinuities based on analyses of lithic assemblages. Population structure indicates a replacement of indigenous Aterian (early modern human) populations by makers of the Iberomaurusian industry ca 18kybp. Population continuity is suggested between the Iberomaurusian and Capsian horizons, and the analysis suggests the expansion of Late Pleistocene populations from the Maghreb into the Sahara as climate improved during the Holocene. Finally, a second population replacement is inferred during the Middle Holocene in the central Sahara coincident with the advent of pastoralism.

The result of a little blog raiding at Dienekes. There’s a pdf from the AAPA full of interesting abstracts here, which I’m working my way through. This one caught my eye-being about North Africa. I t mentions the replacement of the Aterians by the IM industry, and the central Saharan population replacement in the Holocene. Unfortunately it doesn’t say who replaced who; the incoming neolithic mediterannoids replacing the Mechtoid Saharans possibly, although it could be another group, as the groups aren’t specified, but being familiar with the desciptions of Neolithic Saharans by various authors that would be my guess.

It also notes the North African (Mechtoid again) expansion into the Sahara which would have been about 12,000 years ago when the Sahara went through a wet phase. A DNA study on the bones of the Mechtoid population from Taforalt have shown them to be mainly of Eurasian mitochondrial types, and they are very similar to to bones  found as far South as Mali. However, it’s quite likely a good proportion of their Y chromosomes were East African and North East African in origin, as some of the populations show up as intermediate to Eurasian and sub Saharan groups of the same era (although not Taforalt).

The Aterian of North Afrca, and the Solutrean of the Iberian peninsula:was there contact between them in the upper Paleothic

The Aterian of North Africa, and the Solutrean of the Iberian peninsula-was there contact between them in the upper Paleothic?

En Espanol desafortunadamente… Anyone who feels like translating the finer details let me know.
ABSTRACT
We present a state of the question on the North African Aterian, examining different hypotheses that posit some kind of relationship of this technocomplex with the Solutrean of the Iberian Peninsula, via the Strait of Gibraltar. Despite the fact that palaeoenvironmental conditions of the Strait area during the last glaciation would have allowed the movement of humans in several moments, the current archaeological record, besides some techno-typological similarities, does not allow us to conclude any kind of Aterian contribution in the formation of the peninsular Solutrean industries. Furthermore, some reflections about the evolution of the lithic industries from the Initial Upper Palaeolithic are made, pointing out the necessity of undertaking a theoretical and methodological renovation, in order to gain a better understanding of the processes of technological evolution in the Upper Paleolithic, and their relationships with prior contexts.

Prehistoric origins of the paleo-Berbers and of the Tuaregs through Saharan rupestral art

Prehistoric origins of the paleo-Berbers and of the Tuaregs through Saharan rupestral art

A link to a translated page By Malik Hachid, a historian who specialises in North Africa and Berbers.

English  version.

French version.

Discovery of a human skull from the Iberomaurusian levels of Taza cave I, Jijel, Algeria

Discovery of a human skull from the Iberomaurusian levels of Taza cave I, Jijel, Algeria

Archaeological excavations were carried out from 1987 to 1990 in the prehistorically inhabited cave site of Taza I (eastern coast, Algeria). Recovered materials included stone and bone artifacts, faunal remains, and a single human skull. A radiocarbon date for the upper cave level from which the skull was found was 16,100 BP. Taza Skull I is from an adult female, very small overall, particularly in the middle facial area. Her measured cranial capacity was only 1,125 ml. However, her cranial and facial shape compare closely with several North African skull series from Columnata and Afalou in Algeria, Taforalt in Morocco, and Hassi-el-Abiod in Mali.

The North Africans before the Neolithic all seems quite closely related to each other, from Mali to Algeria. Unfortunately I can’t locate more on this.

Extension into the Sahara of the Mechta Afalou type

Extension into the Sahara of the Mechta Afalou type

(EXTENSION SAHARIENNE DU TYPE ANTHROPOLOGIQUE DE MECHTA-AFALOU)-link to (poorly) translated page

Unfortunately in French, which I can understand basically. I’m a useless translator, but the gist of it Is that the North African Mechtoid population extended as far south as Mali and Niger.

It describes some of the crania from various sites. Taforalt and Afalou in particular had wide noses, and a marked prognathism, characteristics usually considered negroid (although the Taforalt mt DNA showed to be mainly Eurasian in origin), and the survival into the neolithic of the mechtoid type in the Western Sahara. It also observes the remarkable proximity of the Western Mechtoid remains to the Cro Magnon remains, with the nose being the main difference between the two, but distance to the Eastern ( Sahaba, Wadi Halfa).

From the DNA studies I’ve read the Mechtoid population seem to be a mix of ancient Eurasian traits (also the origin of the Cro Magnon population) and East African traits from the upper Egypt area. The population expansion from upper Egypt seemed to lose its strength in Morocco, and the Far Western crania show less sub Saharan influence. These people were swamped by newcomers from the near in East in the Neolithic, and possibly in an earlier expansion from the same area prior to 12,000 kya.

Anyone who can find a translation of this into English.. please let me know!