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SW African Bantu matrilineages

Prolific researcher Chiara Barbieri has put online another interesting study on African genetics, this time about the Bantu populations of Southwestern and Central-Southern Africa (i.e. Namibia, Angola, Botswana and Zambia).
Chiara Barbieri et al., Migration and interaction in a contact zone: mtDNA variation among Bantu-speakers in southern Africa. bioRXiv 2014. Freely accessible (pre-pub) → LINK

ABSTRACT

Bantu speech communities expanded over large parts of sub-Saharan Africa within the last 4000-5000 years, reaching different parts of southern Africa 1200-2000 years ago. The Bantu languages subdivide in several major branches, with languages belonging to the Eastern and Western Bantu branches spreading over large parts of Central, Eastern, and Southern Africa. There is still debate whether this linguistic divide is correlated with a genetic distinction between Eastern and Western Bantu speakers. During their expansion, Bantu speakers would have come into contact with diverse local populations, such as the Khoisan hunter-gatherers and pastoralists of southern Africa, with whom they may have intermarried. In this study, we analyze complete mtDNA genome sequences from over 900 Bantu-speaking individuals from Angola, Zambia, Namibia and Botswana to investigate the demographic processes at play during the last stages of the Bantu expansion. Our results show that most of these Bantu-speaking populations are genetically very homogenous, with no genetic division between speakers of Eastern and Western Bantu languages. Most of the mtDNA diversity in our dataset is due to different degrees of admixture with autochthonous populations. Only the pastoralist Himba and Herero stand out due to high frequencies of particular L3f and L3d lineages; the latter are also found in the neighboring Damara, who speak a Khoisan language and were foragers and small-stock herders. In contrast, the close cultural and linguistic relatives of the Herero and Himba, the Kuvale, are genetically similar to other Bantu-speakers. Nevertheless, as demonstrated by resampling tests, the genetic divergence of Herero, Himba, and Kuvale is compatible with a common shared ancestry with high levels of drift and differential female admixture with local pre-Bantu populations.

Figure 1: Map showing the rough geographical location of populations, 
colored by linguistic affiliation. Abbreviations of population labels are 
as specified in Table 1.

In spite of the Bantu-centric approach of the study, which also has its merits, my greatest interest is rather in the less typically Bantu lineages, which speak of admixture with several pre-Bantu populations.
In this sense I find the following highlights:

Fig. S2 (annotated in green by Maju): CA plots based on haplogroup frequencies. Left: all the dataset, right: excluding outliers.

L3d and L3f founder effect:
The Himba and Herero, as well as the non-Bantu pastoralists Damara make one distinctive cluster defined by the high frequencies of haplogroup L3d, as well as L3f (not present among the Damara but found among the Kuvale). As discussed in the paper, the Himba and Herero may be related to the Kuvale of SW Angola but they have notable differential levels (or directionality) of aboriginal admixture. 
As both L3d and L3f are present in West and East Africa alike, it is interesting to track the specific subhaplogroups implicated in this founder effect, something done in fig. 4. 
The main L3d sublineage is L3d3a1, whose haplotype network shows a largely Khoisan centrality (not Damara) although this node is shared also by some unspecified “other Bantu”. The Southern Africa specificity of L3d3a was already noticed in the past (see here). So it is very possible that we are before an aboriginal Southern African lineage, maybe arrived with the first Khoisan Neolithic (or whatever other ancient flow) rather than a Bantu-specific founder effect. 
The main L3f subhaplogroup is L3f1b4a, which seems more specifically Bantu, with a major branch concentrated among the Himba, Herero and Kuvale. This lineage is not found among the Damara in spite of the other strong affinity of this Khoisan population towards the Himba and Herero. L3f1b is found in Southern Africa, Kenya and Oman (per Bihar 2008), so we are probably before a distinctive East African element, not too likely to be genuinely Bantu but possibly just assimilated into Bantu ethnic identity. 
Even if both lineages converge in the Himba and Herero, they are almost certainly different inputs, one of Damara (herder Khoisan) origin and the other of Bantuized East African origin maybe.
L1b founder effect:
L1b is essentially a West African lineage concentrated in the Sahel area from Chad westwards (although L1b1a2 is from the Nile basin). A particularly high frequency population are the Fulani pastoralists, original from the Westernmost African plateaus, who ruled many kingdoms in West Africa between the collapse of the colonial rule by Morocco and the consolidation of the European conquest of the continent.
As this study does not dwell in sublineages, we cannot understand the most likely specific origins of it among several Southern African populations, specifically the pooled NE Zambians (13%) and the Fwe and Shanjo of SW Zambia (24-27%).
In any case it is a notorious founder effect, almost absent in other Bantus of the area (0-10%).
Typical L0d Khoisan admixture:
This element is concentrated in Botswana (~25%) and with highest frequencies in the SW Kgalagadi (53%). It is also important among the Kuvale of SW Angola (21%). Other Bantu populations in this dataset have frequencies under 10%, some even zero. The Damara have 13%.
We know from previous studies that it is also found at high frequencies among the Xosha of South Africa (L0d3).
While L3h appears marked in the graph, the lineage is in fact absent in all populations except at very low frequency among the Kuvale (2%), so it does not seem actually of any relevance. 
Less typical L0k around SW Zambia:
While L0k is generally considered an aboriginal Southern African lineage it has a much more northernly distribution than the more common and surely older L0d. Its area of greatest commonality seems to be SW Zambia (see here and here).
This study confirms this distribution:

Supplementary Figure S3[A]: Haplogroup frequencies of important haplogroups in the populations studied here. A: Haplogroups L0d and L0k.(…)

The size of the circles is proportional to the sample size.

High frequencies of L1c (Pygmy admixture marker) among Southern African Bantus:
An interesting element is the commonality of L1c, typical of Western Pygmies and some other populations from Gabon (possibly representative of the wider West-Central Africa jungle region, not too well studied otherwise), among almost all Bantu populations in this dataset. 
The exceptions are the Herero, Himba, Kgalagadi and Tswana (0%), as well as the NE Zambians (4%). All the rest have frequencies between 12% and 30%. Even the non-Bantu Damaras have 11% of it.
In my understanding this almost certainly implies a notable level of admixture with Western Pygmies of the Bantus from especially Angola and West Zambia. A phenomenon that may be widespread in Central-West Africa. 
It is notable however that at least many of the populations with the highest likely Khoisan admixture (in its various forms, discussed in the previous sections) have the lesser frequencies of L1c (Pygmy admixture). So to a great extent these two aboriginal influences in Bantu mtDNA seem mutually exclusive and were probably produced after settlement rather than “on the march”. 
This in turn arises some interesting questions about the ethnic geography of Africa before the Bantu expansion. 

Update: I just noticed that Ethiohelix has parsed the haplogroups’ frequency into a very helpful chartLINK.

See also:
 

Hunter-gatherers, acorns and tooth trouble

It has been commonplace to believe that hunter-gatherers had good tooth health and that it was farming what caused dental problems because as cereals became a staple. There was good reason for that: caries were detected only rarely among hunter-gatherer remains (0-14%) while early farmers had much such painful problems much more frequently.
However the Upper Paleolithic people of Taforalt caves (Rif, North Africa), some 14,000 years ago (Oranian culture), had caries in 51% of adult teeth, a frequency comparable to those of early farmers.
This is attributed to the very high levels of nut consumptions, particularly acorns but also pine nuts, juniper berries, pistachios and wild oats. The number of acorn remains found is so large that the archaeologists had to conclude that they were used as year-long staple.

Late Upper Paleolithic of North Africa
· Iberomaurusian, aka Oranian, is shaded in dark green ·
· The core area of Capsian is shaded in gray-blue ·
(credit: Locutus Borg (anticopyright))
Taforalt people had hand mills, which they used to process some of these nuts, most likely the acorns, whose consumption as bread has been documented since antiquity.
Another finding are esparto grasses, which the authors believe were used in basketry. However I must mention that this versatile fiber has known many uses, being documented in Neolithic clothing of nearby Andalusia, used for some types of shoes even today and, of course, being a prime material for rope-making.

Esparto bale
Oranian culture dates to c. 22,000 years ago, with likely (partial?) roots in the Southern Iberian Gravetto-Solutrean (hence the name Iberomaurusian, although the culture as such is not known in Iberia). It was replaced in the Epipaleolithic by Capsian culture, with ultimate roots at the Nile (and hence the most likely vector of Afroasiatic languages leading to Tamazigh, aka Berber).
Source: PhysOrg.
Ref. Louise T. Humphrey et al., Earliest evidence for caries and exploitation of starchy plant foods in Pleistocene hunter-gatherers from Morocco. PNAS 2013 (pay per view, free after 6 months) → LINK [doi: 10.1073/pnas.1318176111]
 
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Posted by on January 9, 2014 in Africa, Morocco, North Africa, Oranian, Paleolithic food

 

Madagascar inhabited long before Austronesian arrival

These findings revolutionize the understanding of the prehistory of the island, until now believed to have remained uninhabited until the arrival of peoples of Austronesian stock some 1500 years ago (with some scattered evidence of earlier inhabitation but nothing too conclusive). New archaeological data pushes back the first colonization period to some 4000 years ago, a time when Malayo-Polynesian culture was still restricted to, roughly, the Philippine archipelago.
Robert E. Deward et al., Stone tools and foraging in northern Madagascar challenge Holocene extinction models. PNAS 2013. Pay per view (6-month embargo) → LINK [doi:10.1073/pnas.1306100110]

Abstract

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar’s known occupational history, and thus the time during which people exploited Madagascar’s environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. 14C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton’i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050–1350, by 14C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. 14C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact.

Notice that this colonization is also older than the Bantu expansion and therefore these settlers must have been pre-Bantu peoples of East African roots.

Source: Al-Hakawati
The sites are located in the North tip of the island, what is consistent with arrival through Comoros, the most natural route between East Africa and Madagascar, which  requires the sailing of some 190 miles (~350 Km) of open sea.
Otherwise the narrowest extent of the Mozambique Channel, between Angoche and Tambohorano, is of some 460 Km. The small island or Juan de Nova (uninhabited except for a military garrison) lies to the south of this other potential sailing route.
The toolkit found in the key site of Lakaton’i Anja includes many microliths, as well as some larger tools, made of chert and obsidian. This last must have been brought from far away, as there are no sources of the volcanic glass in Northern Madagascar.

An important point is that these new dates show that human inhabitation did not kill the Malagasy megafauna right away but that instead humans and giant animals shared the environment without immediate catastrophic consequences, which would only happen in the last two millennia.
 

Indian Microlithic industry almost contemporary of Western initial UP and LSA

Mehtakheri toolkit
That is what a new study has found, albeit on just one date. Based on that they argue that the recent claim by Mellars et al. (see also here) about an extremely late date for the migration out of Africa (OOA) becomes more plausible.
Sheila Mishra et al., Continuity of Microblade Technology in the Indian Subcontinent Since 45 ka: Implications for the Dispersal of Modern Humans. PLoS ONE 2013. Open accessLINK [doi:10.1371/journal.pone.0069280]
However considering the pivotal role played by South Asia in the genetics of Humankind after the OOA it is still impossible that this microlithic industry corresponds with that process, because the migration and successive Eurasian expansion must:
  1. Have minimal dates of well before 60-55 Ka ago, time when the presence of H. sapiens becomes undeniable from Palestine to SE Asia and Australia
  2. Go at least largely through South Asia; because the distribution and basal diversity of mtDNA M and R, as well Y-DNA F demand it without any reasonable alternatives. 
The authors themselves acknowledge that the finding is inconclusive in this debate but they choose to lean for a revised Mellars-style interpretation on their own subjectivity.
Their hypothesis is not exactly like Mellars et al. These proposed an extremely late (c. 40-35 Ka BP) OoA, which would imply also extremely late colonization of East Asia and Australasia by Homo sapiens (via South Asia). In order to “explain” the lack East Asian blade-like technologies (necessary for the old professor’s ideas about “modern human behavior”) they proposed that the Eastern colonization was led by small populations who somehow lost the technology. But well, as I discussed back in the day, the hypothesis does not stand.
Mishra’s revised hypothesis is somewhat more coherent (but still very unlikely): she proposes that East Asia and Australia were actually colonized with Middle Paleolithic technology (neither blades nor microblades) in the time demanded by archaeological data and that South Asia instead was not colonized by our species until c. 45,000 BP, possibly because there was some kind of intelligent archaic hominin (Hathnora?), which blocked the expansion of our species initially.
However the hypothesis is still plagued by problems:
  1. As I said above, any model that dictates that South Asia was not central to the expansion of Homo sapiens in Eurasia and surroundings must be wrong: genetics demand otherwise. A settlement of South Asia that is posterior to that of East Asia, Papua and/or West Eurasia (other than the initial Arabian trailblazers or boaters) simply does not make any sense.
  2. The African microblade technology is still quite older (70-60 Ka BP) than the South Asian findings and the similitude may well be a mirage or a matter of convergent evolution. Not the only time that people reinvent the same thing separated by time and space: look for example at Neolithic, which was developed at least in four separate regions of the World, maybe more; or look at the Solutrean style of retouch, used in many different Paleolithic cultures separated by time and space (Africa, Europe, America, etc.)
  3. It would require that Homo sapiens would travel through Altai and all the evidence in this North Asian keystone region, a necessary corridor for transcontinental travel before the domestication of camels (or at the very least horses), indicates that it was inhabited by “archaic” hominids (Neanderthals, H. erectus/Denisovans) until c. 47 Ka BP, when industries related to those of West Asia and Europe show up (at later dates associated to H. sapiens remains).
The facts:
A C14 date was obtained for the site of Mehtakheri (near Barwah, Nimar region, Madhya Pradesh) annotated as: >42,900 BP, > 46,555 calBP, >45,028 – 48,081 (68% CI range for the calBP date). Another C14 date from the same site is much more recent (34,380 ± 991 calBP).
They also obtained five of OSL dates for section 2 ranging from 41.6(±3.3) to 47.0(±4.9) Ka ago. Another date for this unit of 55.5(±5.8) was not used by the authors because it corresponds to an unstudied layer.
Section 3 has older dates (65-78 Ka) but it corresponds to the Middle Paleolithic.
The microlithic industry seems to continue in South Asia until the Iron Age, suggesting that Neolithic and later developments did not substantially alter the demography of the subcontinent. 
All this is very informative but the conclusions suggested don’t seem to make any sense. It is much more logical to infer that H. sapiens left Africa with an MSA-like Middle Paleolithic toolkit that was not related to the Nubian culture (the dead horse being beaten once and again by both Mellars and Mishra) but to other ill-defined groups of possible South African affinity (as claimed by Petraglia). Insisting on the Nubian techno-complex, when we do not know it reaching beyond Dhofar (i.e. they did not reach the Persian Gulf “oasis”, unlike Petraglia’s trailblazers or Armitage’s Jebel Faya findings) is taking the part for the whole, as if there was not already a much more widespread and diverse African Middle Paleolithic (MSA, Lupenbiense, Aterian) in those times already.
Instead these data may indicate a relation of some sort with West Eurasian Upper Paleolithic and African Late Stone Age, which are of roughly those dates. This tentative relationship does not imply migration but would just need some cultural contact. 
It would be interesting to know more about the MP-UP transition in the area around Arabia Peninsula in order to develop better theories on this tripartite interaction between the West Eurasian early UP, the African early LSA and the South Asian early microlithic industry. These very possible cultural interactions fit well within the wet phase of the Mousterian Pluvial (c. 50-30 Ka ago).

Update (Jul 11): “microliths” that are not microliths

I just looked for the first time at the technical issue of what is a microlith (~1 cm long, ~0.5 cm wide) and the published toolkits only seem to have one microlith senso stricto: the J4 point. All the rest have lengths of 2 cm or larger, often 5 cm or more.

The presence of some microlith-sized pieces (usually points) in early UP cultures is almost standard: Emirian, Chatelperronian, Aurignacian and Gravettian all them have occasional “microliths” (measured by size) an in all cases these are points, exactly as happens in Mehtakheri.

So these toolkits seem to have more relationship, if anything, with Western Eurasian early UP ones, which are roughly contemporary (Emirian is the only clearly older one).

Furthermore, archaeologist Millán Mozota sees even similitudes with Mousterian flaking style (see comments):

Bladelet flaking is a typical flaking strategy for this blank type
(small pebbles). Specially if the raw material itself is of good enough
quality.

It has been documented, for high quality quartz on
Mousterian sites, like in Grotte Breuil and, if i recall correctly,
other sites in that area of the Italian Peninsula.

Being also puzzled because the inventories described suggest a strong blade/bladelet component, instead of microblades. 

 

Mellars 2013: second round

As I mentioned before, I have already got copies of the controversial study by Paul Mellars et al., which argues for a very late colonization of Eurasia. It includes some aspects not dealt with in the first round, when I could only access the supplemental material. 
Paul Mellars et al., Genetic and archaeological perspectives on the initial modern human colonization of southern Asia. PNAS 2013. Pay per view (6-month embargo) → LINK [doi:10.1073/pnas.1306043110]
Maybe the most important is the very striking visual comparison between proto-LSA African microlithic industries and post-UP South Asian microlithic ones:

While it is maybe easy to dismiss the patterns drawn on ostrich shells in Africa and South Asia as not really looking the same at all and therefore likely coincidence, the visual comparison of the industries is much harder to reject. It does indeed pose a mysterious apparent link similar to others that are hard to explain like the similitude between Chatelperronian and Gravettian (not so long ago treated together as “Perigordian”) or the hammering insistence by some rather marginal academics on the similitudes between the SW European Solutrean culture and the (much more recent) North American Clovis industry. 
Sure: impressive and intriguing. But when it comes to chronology the Mellars hypothesis seems to fail terribly. While the African microliths are pre-LSA and therefore from before ~49,000 years ago in all cases, the South Asian ones only show up mostly since c. 34-38,000 years ago, more than ten millennia later. Mellars makes this figure 40-35 Ka and then just 40 Ka for the following graph, which in fact misrepresents Petraglia’s model and data in a key issue (see below):

It must be emphasized here that Petraglia’s data and model, at least for what I know it, implies an hiatus between c. 110 Ka and c. 80 Ka BP, hiatus for which there is no archaeological data of any kind in South Asia. Therefore neither side graph should suggest continuity to the past before ~80 Ka, allowing at most for a highly hypothetical dotted line (as in Petraglia 2010):

Also there is nothing in Petraglia’s work that could suggest discontinuity at the Toba ash layer, as suggested by Mellar’s version, rather the opposite: continuity is very apparent in Jwalapuram:

Jwalapuram industries (from Petraglia 2007)

Quite conveniently Mellars ignores Petraglia’s data again, which suggest continuity before and after microlithism in Jurreru Valley and then also finds a transition towards UP (“blade and bladelet”, as well as “backed artifacts”) technologies since c. 34 Ka BP. 
But regardless, I’m pretty sure that Prehistory-savvy readers have already noticed a major issue in all this chronology: we are talking of dates that are almost 20,000 years after the colonization of West Eurasian by H. sapiens with “Aurignacoid” technologies, which are dated to before 55 Ka BP in Palestine (OSL), to c. 49 Ka BP in Central Europe and to c. 47 Ka BP in Altai (C14 calibrated). 
And those who are also familiar with Eurasian population genetics are by now shaking their heads in disbelief and claiming to heaven and hell alike. Because West Eurasians derive, at a late relative date, from Tropical Asians and therefore, if our core ancestors were already separated before 55 Ka BP, there is just no room for the Tropical Asian (and Australasian) expansion that must have preceded the Sapiens colonization of the West Eurasian Neanderlands.
(Those unfamiliar with the basics of Eurasian population genetics, see here).
So there is no way that the Out of Africa migration could be dated to just c. 55 Ka BP, as Mellars does (after grabbing hard the burning nail of conjectural coastal sites now under the sea, which would have to account for some 15-20,000 years of Eurasian prehistory on their own).
In fact it is also impossible from the viewpoint of Australian chronology, which again needs to go after the settlement of Tropical Asia but surely before that of West Eurasia. 
So, regardless of the striking visual comparison between African and Indian industries, which is no doubt the “bunny in the hat” here, the Mellars hypothesis simply doesn’t stand. 
Was there another cultural (surely not demic) flow from Africa to South Asia c. 40-35 Ka BP? Maybe. Or maybe it is just one of the many hard-to-explain coincidences in stone industry design. But whatever it is, it just cannot be the Out-of-Africa migration, unless one is ready to accept that Aurignacian and related European rock art, as well as Australian rock art, for example, are the product of archaic homo species (something that I am sure that Mellars won’t admit to: it just goes against his “modern human behavior” prejudices). And, even then, it just doesn’t add up either.

PS- Petraglia himself finds Mellar’s alternative model untenable. From ABC Science (emphasis mine):

… Professor Michael Petraglia, an archaeologist from the University of Oxford disputes Richards’ and Mellars’ argument. 

Petraglia says there’s not enough evidence to rule out an earlier colonisation before the eruption of Mount Toba. 

“The research reported by Mellars and colleagues is riddled with problems,” he says. 

Petraglia says that the similarity between tools used in Africa
60,000 years ago and those from Asia dating to around 35,000 years ago
is not a consequence of direct migration.


“These toolkits are separated in time by more than 20,000 years and distances exceeding several thousand miles.” 

He questions the evidence supporting a migration along the coast. He
says that surveys of ancient shorelines have not revealed any evidence
for human settlements anywhere along the Indian Ocean shore between
55,000 and 50,000 years ago.

He also says genetic dating should be treated cautiously. 

“Most geneticists will admit that genetic dating of the out-of-Africa
event is tenuous, at best. Published genetic ages for out-of-Africa
range anywhere between 45,000 to 130,000 years ago.

Petraglia
says his team is currently conducting archaeological fieldwork in
Arabia, India and Sri Lanka they expect will show that the story of
human dispersal from Africa is complex.

“What we can agree on is that little research in these key geographic
regions has been conducted and much more evidence needs to be collected
to support or refute the different theories,” says Petraglia.

 

Mellars challenges the ‘early out of Africa’ model

I do not have yet access to this potentially key paper, so first of all I want to make an appeal here to share a copy with me (→ email address). Thanks in advance. Update: got it (thanks to all who shared, you people are just great!) I will review it again as soon as possible.

Update (Jun 18): complementary review of the full paper now available here.

Paul Mellars et al., Genetic and archaeological perspectives on the initial modern human colonization of southern Asia. PNAS 2013. Pay per view (6-month embargo) → LINK [doi:10.1073/pnas.1306043110]

Abstract

It has been argued recently that the initial dispersal of anatomically modern humans from Africa to southern Asia occurred before the volcanic “supereruption” of the Mount Toba volcano (Sumatra) at ∼74,000 y before present (B.P.)—possibly as early as 120,000 y B.P. We show here that this “pre-Toba” dispersal model is in serious conflict with both the most recent genetic evidence from both Africa and Asia and the archaeological evidence from South Asian sites. We present an alternative model based on a combination of genetic analyses and recent archaeological evidence from South Asia and Africa. These data support a coastally oriented dispersal of modern humans from eastern Africa to southern Asia ∼60–50 thousand years ago (ka). This was associated with distinctively African microlithic and “backed-segment” technologies analogous to the African “Howiesons Poort” and related technologies, together with a range of distinctively “modern” cultural and symbolic features (highly shaped bone tools, personal ornaments, abstract artistic motifs, microblade technology, etc.), similar to those that accompanied the replacement of “archaic” Neanderthal by anatomically modern human populations in other regions of western Eurasia at a broadly similar date.

A review has been published at Live Science.

South Asian artifacts from ~30-50 Ka BP.

By “genetic evidence” they obviously mean “molecular clock” nonsense, so it is not evidence at all but mere speculation. However I am indeed very interested in knowing in detail what they mean by “archaeological evidence”, because they seem to get into direct confrontation with much accumulated evidence, first and foremost all of Petraglia’s research in both India and Arabia but also with the quite strong evidence for pre-60 Ka human presence in Australia and growing evidence for pre-60 Ka modern humans in SE Asia (in some cases even as old as 100 Ka). 
It must be said that Paul Mellars has been criticized before a lot for several reasons but very especially for his adherence to the quite speculative “modern human behavior” conjecture and, relatedly, bigotric attitudes against Neanderthal intellectual capabilities, based on nothing too solid. Therefore I’m generally skeptic about what Mellars has to say on this matter because this kind of conclusion is what one would expect from him. 
However Mellars is certainly a distinguished academic and, even if prejudiced and stuck to his own old-school and somewhat Eurocentric interpretations, he knows his trade as archaeologist and prehistorian. So he may be onto something, even if it is not exactly what he wants us to believe. 
For example, it is not impossible that this research may have, unbeknown to the authors, found evidence of a secondary OoA wave (maybe related to the spread of Y-DNA D and mtDNA N?) or even a distinctive evolution in Southern Asian technology prior to the expansion of Western Eurasia. 
It is interesting that they suggest that the 80-60/50 Ka toolkits of India would have been made by Neanderthals, when they are not describing them at all as Mousterian, the almost exclusively Neanderthal techno-culture, or Mousterian-related.
I have some difficulties judging before reading the whole study. However the supplemental material (quite extensive) is freely accessible and for what I can see there:
  1. They dedicate much text to attempt to justify a particular version of mainstream “molecular clock” hypothesis, which are clearly broke in my understanding. The kind of arguments “rebated” are more or less what I have been putting forward since many years ago. Ironically their “molecular clock” estimates make N and R much older than M, what I absolutely oppose (just count mutations downstream of the L3 node).
  2. No real attention is given instead to the geographical structure/distribution of major mtDNA haplogroups, only mentioned in relation to “molecular clock” speculations.
  3. The criticism of the African affinity of the Jwalapuram (Jurreru Valley) cores (Petraglia 2007) focuses on dismissal of any possibility of comparison, rather than on alternative comparisons. 
  4. Another “criticism” is that there is no apparent connection between Jwalapuram and the Nubian Complex (why there should be any?, it is not the only East African techno-culture, nor the only group that shows indications of traveling to Arabia in the Abbassia Pluvial).
  5. Also it is “criticized” that the most comparable African culture, Howiesons Poort) is not recorded before c. 71 Ka BP (what IMO may indicate late cultural dispersals to Southern Africa from East Africa, for example, but, hey!, Mellars is fencing off balls like crazy at his conservative goal). 
  6. They find clear similitudes between Indian and African microlithic industries (apparently related to the development of “mode 4” in both areas, as well as in West Eurasia). Indian industries are dated to c. 38-40 Ka BP, while African ones are dated to c. 49 Ka BP (Kenya) or later. However West Eurasian ones have dates as old as 55 Ka BP (not for Mellars, who remains stuck in older date references which he describes as ∼40–45 ka [calibrated (cal.) before present (B.P.)]), what really suggest that we are talking here not of the “out of Africa” but of the West Eurasian colonization process (necessarily from further into Asia, genetic phylo-geographic structure demands) with offshoots to the nearby regions. 
  7. Another element of late Africa-India “similitude” they find is “the remarkable, double bounded criss-cross design incised on ostrich eggshell”, dated in India (Patne) to at least ∼30 ka (cal. B.P.), much earlier in South Africa. For Mellars this is beyond the range of either pure coincidence or entirely independent and remarkably convergent cultural evolutionary processes. Hmmm, really? Or are we before a clear case of wishful thinking as happens with the Solutrean-Clovis relationship hypothesis? Isn’t it 30 Ka BP anyhow well beyond any reasonable expectations for the OoA time frame, including Mellar’s own conjectures?
  8. Mellars accepts the paradox that the geographical limits of these highly distinctive microblade and geometric microlithic technologies are confined to the Indian subcontinent, with no currently documented traces of these technologies in regions farther to the east. And then makes up excuses for it, such as biological and cultural bottlenecks caused by “founder effects”, mysteriously leading to a loss or simplification of cultural and technological know-how, as well as fininding new and contrasting environments (in the same latitudes?!)
  9. Even in the case of Arabian colonization, Mellars shows to be in a very defensive attitude, admitting only to the reality of the Palestinian sites with clearly modern skulls, as well as to the area of Nubian Complex colonization (on whose peculiarities he insists a lot, as if it would be the only expression of the wider MSA techno-complex), disdaining all the other MSA colonization areas and, often ill-defined, variants.
In brief, for what I could see in the supplemental material, along with some potentially interesting references to the relative cultural community spanning from East Africa to South Asia at the time of emergence of “mode 4” industries, it seems that Mellars and allies are essentially putting the cart (their models) before the horses (the facts), what is bad science. 
In 2008, Zilhao and d’Errico angrily accused Mellars of being an obsolete armchair prehistorian (different words maybe, same idea). Back in the day I was tempted to support Mellars but nowadays I must agree that he is clearly stuck in a one-sided interpretation of prehistory whose time is long gone. Whatever the case I welcome the debate and can only hope that will help to produce even more evidence to further clarify the actual facts of the Prehistory of Humankind.
 

New sublineages in Y-DNA haplogroups A3 and B2a

Improving the knowledge of African genetics.
Rosaria Scozzari et al., Molecular Dissection of the Basal Clades in the Human Y Chromosome Phylogenetic Tree. PLoS ONE 2013. Open accessLINK [doi:10.1371/journal.pone.0049170]
Abstract

One hundred and forty-six previously detected mutations were more precisely positioned in the human Y chromosome phylogeny by the analysis of 51 representative Y chromosome haplogroups and the use of 59 mutations from literature. Twenty-two new mutations were also described and incorporated in the revised phylogeny. This analysis made it possible to identify new haplogroups and to resolve a deep trifurcation within haplogroup B2. Our data provide a highly resolved branching in the African-specific portion of the Y tree and support the hypothesis of an origin in the north-western quadrant of the African continent for the human MSY diversity.

Figure 1. Revised topology of the deepest portion of the human MSY tree.
The names of the mutations genotyped are indicated on the branches (green, mutations from the paper by Karafet et al. [14]; black, mutations from the paper by Cruciani et al. [16];
red, previously undescribed mutations, see text). For the sake of
clarity, the internal structure of haplogroups B-M108.1 (2 branches) and
B-50f2(P) (8 branches) is not shown (black triangles). The phylogenetic
position of mutations mapping within haplogroup CT is shown in Figure S1.
Dashed lines indicate putative branchings (no positive control
available). The microsatellite intermediate allele DYS449.2, that was
found to delineate new phylogenetic structure in human Y chromosome
haplogroup tree [42], was not observed in 19 Y*(xBT) and 4 B chromosomes analyzed.

Notice that the nomenclature per ISOGG is right now as follows:

  • A1b-V148 is now known as A0
  • A1a-V4 retains the name A1a
  • A2-V50 is A1b1a
  • A3-M32 is A1b1b
    • A3a-M28 is A1b1b1
    • A3b-M144 is A1b1b2

See ISOGG for more details.

 
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Posted by on May 17, 2013 in Africa, African genetics, Y-DNA