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Saturday, September 19, 2009

E-M34: Designation as "African" presents a Dilemma?

Earlier on this year, the present author of this site had an exchange with a chat room regular and the author of a paper titled "Y Haplogroups, Archaeological Cultures and Language Families: a Review of the Possibility of Multidisciplinary Comparisons Using the Case of E-M35", going by the name of Andrew Lancaster, on issues pertaining to the origins and demic diffusion possibilities of E1b1b subclade 'E-M34'. There are some observers out there who basically prefer to treat E-M34 as an isolated [standalone] lineage on its own, away from all its other E-M35 siblings, and mute the fact that this lineage essentially signifies recent common African ancestry. In what appears to be ironic, sections of these same observes are inclined to use E-M34 as primarily a marker of "external gene flow" into Africa. To put the underlying reasoning by such observers to test, the present author of this site decided to query the aforementioned Lancaster on his views.

In the mentioned paper, Lancaster sees the E-M34 clade more as ultimately a marker of demic diffusion "into Africa" as opposed to "out of Africa"; he invokes geneticists Cruciani et al. (2004) as his primary reference-sources, to justify his viewpoints. Here, he recites the claim that from a distribution standpoint, E-M34 clusters appear to be absent in nations immediately neighboring Ethiopia [like Sudan], and the supposed greater intra-clade diversity found in the Arabian peninsula than in Ethiopia. When repeatedly told that the geographical location of the contemporary nation of Ethiopia need not be the original African territory of the African forerunners of E-M34 carrying Ethiopians, or that for E-M34 to be deemed "African", it need not be predicated on it having to have originated in what is now Ethiopia, and that instead these forerunners could have originated in a more northern latitude in the geographical sphere of the eastern Sahara, Lancaster's reaction is to present what is now part of the contemporary nation of Egypt as a "concession" on his part. According to this "concession", he is willing to give into the possibility that E-M34 originated in what is now part of Egypt and thereafter spilled over to the Levant to its east, and coastal north African areas to its west. He points to the relatively visible, not necessarily predominant, distribution of E-M34 markers in these areas, and in some cases, sporadic incidences of paraphyletic examples of E-M34. Lancaster seems to seize on the condition of "Semitic" speaking in Ethiopia as something that further justifies his viewpoint.

Lancaster's so-called "concession" revolving around an Egyptian origin is all fine and dandy, but even here, he refuses to see an Egyptian origin as essentially an "African" origin as well. He refuses to get in touch with the reality that Egypt is part of Africa, and therefore, that the two are not mutually exclusive of one another. Logic intimates that what is Egyptian is by default also African, but for some reason, when it comes to things African, such no-brainers suddenly belie logic. He insists that it would be better [on his account] to perceive Egypt in terms of the over-time-changing and subjective Eurocentric-created geopolitical constructs like the "Middle East" rather than the less subjective designator for the continent to which Egypt belongs. In other words, his "concession" has a precondition attached to it; that is, as long as Egypt is viewed as "Middle East", which is tacitly supposed to be mutually exclusive of "Africa". It is against this backdrop, he chooses to interpret an African origin as needlessly implicating "all of Africa"; such "problems" or "issues" of course, never arise when dealing with any other continent.

On the issue of distribution, Lancaster's recitation of authors [namely Cruciani et al. (2004)] who proclaim to have come up short where findings in territories immediately neighboring Ethiopia [like Sudan] is something that deserves closer inspection. Cruciani et al. (2004) themselves don't quite go out on a limb to rule out an "eastern African" origin, but point out two "observations" that point to, in their words, a "Near Eastern" origin:

Although the frequency distribution of E-M34 could suggest that eastern Africa was the place in which the haplogroup arose, two observations point to a Near Eastern origin: (1) Within eastern Africa, the haplogroup appears to be restricted to Ethiopia, since it has not been observed in either neighboring Somalia or Kenya (present study) or Sudan (Underhill et al. 2000).

A number of observations here: Firstly, it is fairly obvious that "eastern Africa" as used here, is a tacit reference to the "sub-Saharan" area of eastern Africa; for if that wasn't the case, then naturally, one would have to assume that Cruciani et al. (2004) are not informed about Egypt being located in "eastern Africa". Moreover, this would be at odds with Mr. Lancaster's "concession". Secondly, the authors here are obviously drawing a far-reaching conclusion from fairly narrow observations made from just two studies that they cite, one of which happens to be their very own—their then present study. The authors study did not include any sample from Sudan, leaving the authors to rely on a single older study.

A comprehensive look back at studies done in Sudan suggest that it is an area understudied, which is interesting, given "Western" academic circles' obsession with eastern African areas; there are very few studies [undertaken by elements of 'Western' academia] that have dealt with that territory, let alone comprehensive region-wide study of Sudan. In any case, if one were to take it as the absolute fact based on a few measly [however instructive] studies undertaken, E-M34 absence or rarity in immediately surrounding [Ethiopia] territories of the likes of Sudan, Somalia and Kenya presents another interesting case.

Like Egypt, territories of Sudan and Somalia are right by the Red Sea, and in many cases, however different the internal clusters, and/or distribution and frequency patterns of markers involved may be, have experienced demic diffusion events involving the same line of clades or macro-haplogroups that now find place on Ethiopian landscape. Ethiopia itself is now essentially a landlocked nation, with the parting away of Eritrea, underlying just how fluid and subjective geopolitical constructs can be, and hence, intellectually not economical to place one's bets [arguments] on purely geopolitical constructs. So, if it were a simple matter of gene flow from the Arabian peninsula or the Levant [seems to be Lancaster's leading impression] of the so-called "Near East", one would think that the probability of E-M34 chromosomes finding their way into Sudan, Somalia, Djibouti, Eritrea, as it has obviously done in Egypt and Ethiopia, should be reasonably high enough.

However, if the mutation itself occurred at some point somewhere in central-eastern Sahara, north of the equator, then it is certainly conceivable a community with a very modest effective population size could have taken a two-pronged dispersal: one in a direction towards the delta region of the Nile River Valley, and the other towards the Ethiopian region. There could have even been an additional one, headed westwards, along coastal north Africa. With such migration, it is not necessary for the migrants to have stayed put in what is now Sudan or say Somalia, and even if they had, negative random genetic drift on settlers forming a community(s) of fairly modest effective population size could have ensured that their numbers in these areas remain at undetectable levels, that is to say, one which could easily evade the foci of the selective and patchy sample undertakings by "Western" academic concerns.

Lancaster made a fuss about paraphyletic E-M34 clades having been detected in the so-called Near East, but not in Ethiopia, based on the few studies that make note of these incidences. As natural, and equally so, he was reminded of the other side of said observations: paraphyletic examples of E-M34 were for instance, noted in a Tunisian sample (Arredi et al. 2004), and an isolated incidence in southern Europe, Bulgarian sample, along with another single one in central Asia (Cruciani et al. 2004), but interestingly enough, not in the so-called "Middle East" either [as per both cited studies used as examples]. Needless to say, it would not make the least sense to pounce on an isolated incidence in a Bulgarian sample or one individual from Central Asia and draw a far-reaching conclusion that this must be the vicinity of where the E-M34 mutation first occurred.

Europe is not exactly the epitome of a comprehensive and wide-variety of distinctive E-M35 clades, and one can make the argument, though to a lesser extent than Europe, that the so-called "Near East" is not a garden of variety either, when it comes to E-M35 chromosomes. Africa, on the other hand, is an entirely different story...naturally. The point being, since it hasn't been phylogenetically demonstrated to date that E-M34 derives from any of the other known E-m35 derivatives in either the so-called Near East or Europe, Africa with its unsurpassed comprehensive range, does not run into that problem.

Furthermore, in many of the areas where E-M34 chromosomes had been detected, as related to Lancaster but not getting through to him, it has been found in tandem with other markers undeniably suggestive of most recent common African ancestry. An example of this is in the Levant, wherein paraphyletic R1 chromosomes [as earlier found in northern Cameroon] where observed in high frequencies in tandem with E-M34 chromosomes in Dead Sea Samples, which interestingly, had far lower Hg J markers than other neighboring so-called "Near Eastern" Semitic-speaking groups; conversely, said Dead Sea sample had much higher incidences of E-M34 than said neighbors, along with the X chromosome G6PD marker, generally stated to be restricted to African samples.

Lancaster somehow managed to mangle up the example, and interpreted it as one that supposedly relies on the notion that if said R1 chromosomes are shared with Africans, then it must necessarily follow that the E-M34 is "African". Continuing with Cruciani et al. (2004),...

(2) E-M34 chromosomes from Ethiopia show lower variances than those from the Near East and appear closely related in the E-M34 network (fig. 2D). If our interpretation is correct, E-M34 chromosomes could have been introduced into Ethiopia from the Near East. The high frequency of E-M34 observed for some of the Ethiopian populations could be the consequence of subsequent genetic drift, which can also explain the lower frequencies (2.3% [Underhill et al. 2000] and 4.0% [Semino et al. 2002]) reported for two large independent samples of Ethiopians.

While Cruciani et al. (2004) claim that the internal variation of Ethiopian showed "lower variances" than those from the so-called Near East, a close look at their own visual aid of the networks in question suggest something different: it shows little distinction between the level of distinctive branching within the Ethiopian index and that of the so-called Near Eastern examples. The distraction that Lancaster offers in reaction to this observation, was simply to query the present author of this blog as to whether he was questioning Cruciani et al.'s genetic credentials. Of course, that very idea is preposterous and immaterial, as a succinct and very specific observation was made about Cruciani et al. (2004) on the diagrammatic interpretation of the respective Ethiopian and "Near Eastern" E-M34 networks, which only needed a direct, and equally succinct and specific rebuttal to the contrary, if the dissident (Lancaster in this case) had one. The diagram in question was this:

Click on the image for better resolution

The subtext accompanied with the diagram reads:
Microsatellite networks of E3b haplogroups. A, E-M35*. B, E-M78. C, E-M81. D, E-M34. Reduced-median and median-joining procedures (Bandelt et al. 1995, 1999) were applied sequentially. A haplogroup-specific weight proportional to the reciprocal of microsatellite variance was used in the construction of the networks. The E-M78 unweighted network (not shown) gave the same quadripartite structure. Unassigned chromosomes (B) showed an intermediate position between clusters α and δ in the unweighted network. Microsatellite haplotypes are represented by circles, with areas proportional to the number of individuals harboring the haplotype. Branch lengths are proportional to the number of one-step mutations separating two haplotypes.

The diagram is there for anyone to examine him/herself, and so, if one wanted to make an argument counter to the one the present author of the blog makes, it should be a fairly straightforward undertaking, without beating around the bush with shallow distractions. The latter part [emphasized in bold] of the aforementioned "second" reasoning provided by Cruciani et al. (2004) just goes to show how much observations made in a particular study are greatly influenced by sampling selections and range by the respective authors of these studies; the differing observations attest to this. If the effect of genetic drift is to be thrown into the mix, as Cruciani et al. (2004) insinuate, then that takes us back to or only reaffirms the point made here earlier, about the effects of that same phenomenon on the demographic history of E-M34 migrants. Interestingly enough, the authors proceed with concluding their segment on E-M34 as follows:

From the Near East, E-M34 chromosomes could also have been introduced into Europe, possibly by Neolithic farmers, but the paucity of E-M34 chromosomes in southeastern Europe (Semino et al. 2004 [in this issue]; present study) weakens this hypothesis. Indeed, as for E-M78δ chromosomes, introduction of E-M34 from Africa directly to southern-central Europe cannot be excluded at the present.

The piece necessitates little further elaboration; it pretty much speaks for itself. The gem in it, of course, is that if E-M34 chromosomes introduced "directly" from Africa to southern Europe is more than probable and explains its distribution there, then why can the same not be true for the so-called "Near East"?

*According to Semino et al.'s report, there is microsatellite indication that much of Ethiopian hg J-M267 examples are of Neolithic provenance...
The majority of J-M267 Y chromosomes harbor the single-banded motif YCAIIa22-YCAIIb22 in the Middle East (>70%) and in North Africa (>90%), whereas this association is much less frequent in Ethiopia and only sporadically found in southern Europe. Considering the distribution of this YCAII single-banded pattern—which, besides the usual stepwise mutational mechanism, could be due to a stable mutational event (one locus deletion or a single-nucleotide mutation in the primer sequence)—we suggest that the motif YCAIIa22-YCAIIb22 potentially characterizes a monophyletic clade of J-M267...According to this interpretation, the first migration, probably in Neolithic times, brought J-M267 to Ethiopia and Europe, whereas a second, more-recent migration diffused the clade harboring the microsatellite motif YCAIIa22-YCAIIb22 in the southern part of the Middle East and in North Africa. In this regard, it is worth noting that the median expansion time of the J-M267-YCAIIa22-YCAIIb22 clade was estimated to be 8.7–4.3 ky, by use of the TD approach (see fig. 4 legend), and that this clade includes the modal haplotype DYS19-14/DYS388-17/DYS390-23/DYS391-11/DYS392-11 of the Galilee (Nebel et al. 2000) and of Moroccan Arabs (Bosch et al. 2001).
If true, this would mean that any "Afro-Asiatic" hg J-M267 from southern Arabia would have had to have been acquainted with the farming subsistence from the Levantine areas, and as such, certain Neolithic social terms associated with such economy would have been available. As noted here before, nothing comes to mind that suggests basic "Near Eastern" or "south Arabian" Neolithic-derived terms in Ethio-Semitic. Kivisild et al. are essentially treating hg J1-M267 as the effective marker for proto-Semitic speakers in Ethiopic populations, as opposed to E-M78 or E-M35 clades, which is odd, because the primary agents of spreading proto-Semitic or proto-Afrisan languages into the "Near East" and the Arabian peninsula in the first place would have largely been E-M35 carriers, who originate from an area where preponderance of evidence—including both genetic particulars and language diversity—places the origin of proto-Afrisan language phylum. This therefore puts hg J carrying groups in the "Near East" and elsewhere on the receiving end of "Afro-Asiatic" language acculturation, not the primary agents of it.

The structuring of hg J clades along linguistic lines within Ethiopian samples simply says that these groups likely merged together from distinctive demographic episodes; one involving the group predominantly comprising of proto-Ethiopic Semitic speakers—likely carrying both hg E-M35 clades and hg J clades—and the other,  predominantly Cushitic speaking groupsthat's just about it; it tells us very little about the specific direction from which the aforementioned linguistically-structured markers respectively arrived—be it from the north or from the southern Arabia, short of comprehensive comparative analysis at the molecular levels between the Ethiopic groups and geographically proximate, exotic, non-Ethiopic groups.

Kivisild et al. were compelled to make J1-M267 into THE telltale marker for the spread of proto-Semitic phylum into the African horn, because they recognized the low to absent incidences of E-M78 in south Arabian samples, which no less were not based on actual sampling of Yemeni population at the time of their observations, but at the same time they had to contend with linguistic reconstructions that place Ethio-Semitic languages into the southern branch of the Semitic phylum. For those who are bent on explaining away autochthonous coming about of Semitic languages on African soil, this element entices the cooking up of theories around an origin in the southern tip of the Arabian peninsula, no matter how tenuous.

One cannot also help but arrive at the conclusion that the presence of E-M34 clades in southern Arabia must have been elusive to the authors in question, and that it may well be serving as a marker of Afrisan diffusion into that region. In Cruciani et al.'s 2004 journal, which the authors rely on, not only had E-M34 markers been reported in the sole southern Arabian sample (Omani), but so had the E-M78 counterparts, and they occur in identical incidences. That said, E3b1c1-M34 chromosomes are visibly prevalent in Ethiopian groups, as they are across the whole stretch of northern Africa.

From the earlier mentioned Semino et al. (2004) study, as it concerns the compatibility of Ethiopian J1-M267 clades with the idea of their introduction by southern Arabians, particularly their nearest neighbors—the Yemeni, it was acknowledged that:
The lower internal variance of J-M267 in the Middle East and North Africa, relative to Europe and Ethiopia, is suggestive of two different migrations.  - Semino et al. (2004)
This revelation to the authors' above is consistent with those reported elsewhere, and may well prove instructive in the quest to determine the duplicity of Ethiopian hg J clades with those in southern Arabia, particularly those of Yemen:
At another extreme, the haplogroup distribution of Yemen shows very limited variation, particularly when compared to neighboring populations, Oman and UAE (3 versus 11 haplogroups each), whereas Qatar is intermediate with a total of seven haplogroups, four of which display frequencies of less than 3.0%. Although Qatar does not approximate the lack of diversity seen in Yemen, the two populations display affinities that are apparent in the MDS plot, in which populations of the Levant are interspersed among the South Arabian populations, with Qatar and Yemen segregating apart from both UAE and Oman. - Cadenas et al. (2007)
The authors figure that one of the underlying causes for this reduction in diversity of Yemeni Y-DNA gene pool, in addition to subsequent expansions masking earlier ones, could be a matter of a "high degree of consanguinity" within the population. Having said that, elsewhere, they wrote:
Median BATWING expansion times based on Y-STR data for the Omani (2.3 ky; 95% CI: 0.6–29.2) J1-M267 chromosomes4 indicate a more recent arrival to the South Arabian populations as compared to the older expansion times obtained for the Egyptian (6.4 ky; 95% CI: 0.6–278.5)4 and Turkish (15.4 ky; 95% CI: 0.4–604.8)12 representatives of this haplogroup. Conversely, in the present study, Y-STR age estimates based on the method described by Zhivotovsky et al46 generated much older values for the J1-M267 haplogroup in Yemen, Qatar and UAE (9.7 +/- 2.4, 7.4 +/- 2.3 and 6.4 +/- 1.4 ky, respectively) than seen in the Omani,4 consistent with an earlier arrival to the region during the Neolithic. The data suggest expansion from the north during the Neolithic (or perhaps more recently), which is also reflected in the lower STR variances in southern Arabia (0.14 for Qatar, 0.15 for UAE, 0.20 for Yemen and 0.27 for Oman4 versus 0.31 in Egypt4 and 0.51 in Turkey12). Subsequently, a series of recent demographic events may account for the high haplogroup frequency of J1-M267 in the populations from the present study.  - Cadenas et al. (2007)
Like Semino et al. (2004) and Luis et al. (2004) before them, these authors too note the higher intra-haplogroup variance in J1-M267 chromosomes in areas to the north of the southern Arabian territories mentioned here both in the "Middle East" and Northeastern Africa than those in populations of said southern Arabian peninsula areas. In light of this, it is important to reiterate, just as the said authors themselves did by citing Semino et al. (2004), that the Ethiopian hg J1 clade gene pool was even more varied than those from the "Middle East" and coastal Northern Africa.

Furthermore, just as the aforementioned authors in the 2004 publications note the older expansion ages for populations to the north of the more southward-oriented populations in the Arabian peninsula, the authors here too arrive at the same conclusion, noting that the expansions appear to have began from the Neolithic times onwards from the north to south along the Arabian peninsula. Yet again, Ethiopian hg J clades in turn show older expansion ages than sections of Northern African and "Middle Eastern" gene pool, which have been affected by more recent demographic events, as have the southern Arabian groups mentioned here.

The estimated upper-end expansion time frame of Yemen's hg J1 gene pool in particular is one that is not inconsistent with that generally associated with the spread of Neolithic farming subsistence, but the more internally more varied hg J1 clades of Ethiopia than those in Yemen (not to mention the distinctive aforementioned paraphyletic clades of Ethiopia), and the rest of the south Arabian groups described here, is inconsistent with an idea of introduction from Yemen, or any other southern Arabian territory for that matter. This is significant, considering that hg J has a considerable presence in Yemeni Y-DNA gene pool; 72.6% according to Cadenas et al. (2007).

The picture is no less different, when it comes to E1b1b1c (E-M123 or its subclade "E-M34")  chromosomes; while Cadenas et al. (2007) cited Cruciani et al.'s (2004) reckoning about the plausibility of Ethiopian E3b1c1-M34 bearing chromosomes arriving from the "Near East", they did not go quite as far as suggesting a "Near Eastern" origin for the clade in any context:
On the other hand, Cruciani et al57 have postulated that the E3b1c-M123 clade may have originated in the Near East, as its presence in East Africa is restricted to Ethiopia (11.2%). The median expansion time for M123 in Egypt is 10.8 ky,4 comparable to the estimated age of M123 STR variation obtained through the method described by Zhivotovsky et al46 for UAE (11.1 +/- 3.9 ky) and Yemen (10.6 +/- 4.1 ky), although allelic differences between these two populations indicate that they do not share a common ancestry. Recent archaeological finds supports a trading relationship between Mesopotamia and the Arabian Gulf region dating back to the Al Ubaid Period (~7000 yBP) as evidenced by the excavation of Ubaid pottery from Mesopotamia in UAE.8–10 Ancient maritime trade routes linking Mesopotamia to the Indus Valley included Dilmun (the island of Bahrain) and Magan (in the southeastern tip of the Arabian Peninsula). It is possible that the close ties between Mesopotamia with both the Nile River Valley and the ancient Persian Gulf region during the Neolithic helped disseminate these haplogroups- Cadenas et al. (2007)
In fact, the authors' language suggests acknowledgment of E3b1c-M123 as more of a marker of African ancestry than one of "back-migration":
The E3b1-M35 sub-haplogroups, M123 and M78, are believed to have spread from East Africa to North Africa and later expanded eastward through the Levantine corridor and westward to northwestern Africa. Although E3b1a-M78 data suggest that this dispersal occurred in both directions,4,34,47 E3b1c-M123 disseminated primarily to the east.4 The distribution of the E3b1-M35 derivatives in Yemen, Qatar and UAE agrees with their arrival by expansion via the Levantine corridor rather than through the Horn of Africa. This route is similar to general patterns of Levantine mtDNA gene flows during the Upper Paleolithic55 to the Neolithic.5,55 This is immediately apparent by the M35 profile of several East African populations. - Cadenas et al. (2007)
Having noted Cruciani et al.'s (2004) postulation, the authors merely note that the trade network between said regions may have facilitated the spread of E3b1c-M123, which was followed by its expansion downward in the Arabian peninsula, wherein it appears to have undergone multiple founder effect—and likely genetic drift thereafter—events, resulting in the patterns noticed in the Arabian peninsula, with different populations having different subsets of E3b1c1-M34 chromosomes, which of course, brings us right back to Cruciani et al.'s (2004) claim of relatively lower internal variation in the Ethiopian E3b1c1-M34 gene pool than those from the "Near East".

Cruciani et al. (2004) provided us with a map of E3b1c-M123 among other E1b1b1 markers, displaying the Y STR network, wherein they tell us that the Ethiopian examples are more closely related than the "Near Eastern" examples, and hence, lesser diversity thereof. As noted here before, an instant look at the map itself doesn't appear to invoke a sense of that much of a difference between the internal diversity of Ethiopian chromosomes and those of "Near Eastern" examples as far as the number of distinctive inter-connecting "branches" that respective haplotypes fall into is concerned, save to say that where said haplotypes are branched-out immediately from one another and having come from populations within the same region or general geography, the Ethiopian examples do appear to display more shorter-length branches in between them than those from the "Near East". The comparison based on the latter phenomenon though, doesn't come from a level playing field; the Ethiopian haplotypes are expected to show relatively shorter branches with respect to one another, because they are highly geographically-proximate populations of the same nation state, whereas those from the "Near East" were pooled from distinct geographical territories spanning the Asian Minor, the Levant all the way to the southern tip of Arabia.

As we've just seen from above, the "Near East" expansions of E3b1c1-M34, likely first in the northward-oriented territories therein, and then from there towards the south, was marked by multiple "founder effect" situations accompanied by genetic drift—positive or negative, resulting in different subsets of E3b1c-M123 developing internally within respective distinct populations of the region. A fairer assessment would be pooling *all* African examples together, and comparing them with the pooled "Near Eastern" examples. Cadenas et al.'s (2007) posting of internal-diversity of E3b1c1-M34 clades per region is consistent with previous data.

Furthermore, the studies posted here all, and more, keep citing that singular Underhill et al.'s (2004) one study wherein E-M34 was not detected in a Sudanese sample, around which Cruciani et al. (2004) raise their "Near Eastern" origin plausibility, for Ethiopian chromosomes. In that same study, interestingly, no hg J clades were observed in the Sudanese sample either; How is that for a reality check? Yet, other studies have noted hg J markers in Sudanese samples. Semino et al. (2004) for their part, refrained from inferring the origin of Ethiopian E3b1c1-M34 clades, only noting that:
The network of E3b1a-M78 and that of E3b1c-M123 are in agreement with the hypothesis of their ancient presence in the Near East and their subsequent expansion into the southern Balkans. The divergence time (TD) (Zhivotovsky 2001) between the Near East and European lineages has been estimated to a range of 7–14 thousand years (ky) ago. Cinniog˘lu et al. (2004) found a high degree of variance of E3b1c-M123 in Turkey, which has been interpreted as being due to multiple founders rather than a single early dispersal event that has remained geographically circumscribed- Semino et al. (2004)
In Turkey alone, we are confronted with a scenario of multiple founder situations; it has implications on the point made herein and that by Cadenas et al. (2007), about this phenomenon having an impact on the pattern of "internal" variation from across a fairly wide region spanning the Asian minor to the southern tip of the Arabian peninsula, when populations therein are pooled together and pitted against that of the more geographically constricted territory of Ethiopia. The high degree of internal variation in Turkey has been attributed to "multiple founders" from different demographic episodes, but Yemeni and other south Arabian populations, as we shall see below [and also revisit info above], display fairly low internal variation for their E-M34 markers, or conversely, high degree of homogeneity...

From Cadenas et al.'s (2007) posting:
As the MDS plot displayed a close affiliation between South Pakistan and North Iran and the former segregated away from the Gulf of Oman populations, the x^2-test was repeated excluding South Pakistan. Although statistically significant differences are still apparent for haplogroup E (x^2 = 10.170, d.f. = 2, P = 0.0062) and R (x^2 = 10.560, d.f. = 2, P = 0.0051), J (x^2 = 2.577, d.f. = 2, P = 0.2757) exhibits an even distribution among Oman, UAE and South Iran. However, a greater homogeneity is observed among the South Arabian populations of Oman, UAE and Qatar for haplogroups E (x^2 = 2.249, d.f. = 2, P = 0.3248), J (x^2 = 4 831, d.f. = 2, P = 0.0893) and R (x^2 = 0.308, d.f. = 2, P = 0.8573). The significant differences in frequency of haplogroups result in detectable clines moving from the South Arabian populations to South Iran and then South Pakistan (E: 18.8, 6.8 and 3.3%; J: 50.4, 35.0 and 25.3%; and R: 11.2, 25.6 and 46.2% for South Arabia, South Iran14 and South Pakistan,30 respectively).  - Cadenas et a.l. (2007)
The above show gradients, wherein hg E is greatest in southern Arabia and decreases as one proceeds northward to southern Iran, and then eastward to south Pakistan, and the same applies to haplogroup J, while the reverse trend is seen in hg R, with the lowest frequencies in southern Arabia. The piece above notes a greater loss of diversity in all three haplogroups involved when it comes to southern Arabia, compared to the other mentioned regions. Yemeni gene pool for these are yet even more limited in their diversity than the aforementioned south Arabian populations of Oman, UAE and Qatar. Recalling the piece cited earlier:
At another extreme, the haplogroup distribution of Yemen shows very limited variation, particularly when compared to neighboring populations, Oman and UAE (3 versus 11 haplogroups each), whereas Qatar is intermediate with a total of seven haplogroups, four of which display frequencies of less than 3.0%. Although Qatar does not approximate the lack of diversity seen in Yemen, the two populations display affinities that are apparent in the MDS plot, in which populations of the Levant are interspersed among the South Arabian populations, with Qatar and Yemen segregating apart from both UAE and Oman. - Cadenas et al. (2007)
Luis et al. (2004) posted an internal variance of  .41 for the Egyptian sample vs. the just .05 internal variance for the Omani sample, as it pertains to the E3b1c-M123 clade. Likewise, the internal variation of Egyptian J clades—J-12f2(xJ2-M172) and J*-12f2(xJ2-M172)—was .45 and .31 respectively, while those reported for the Omani sample were .40 and .27 respectively. There is apparently greater disparity between the reported values for the two samples in the case of the E-M123 marker than the J clades, but the common element here is the relative greater internal variation in the Egyptian sample vs. the Omani. On the other hand, Cadenas et al. (2007) report the following internal variance values for the following groups respectively: For UAE the value was .25 [E3b1c-M123] and .15 [ J1-M267], while for Yemeni, the values were .14 [E3b1c-M123] and .20 [J1-M267]. Qatar did not report for any E3b1c clades, but did have a value of .14 for J1-M267. The level of diversity demonstrated above in eastern African examples of E3b1c-M123 and J1-M267 markers, including those from Ethiopia, is inconsistent with a south Arabian origin. 

The plausible scenario for introduction of hg J1 clades in Ethiopian populations is more likely one wherein the J1 clades arrived early in the continent, whether due to in situ origin or back-migration, and was picked up by the ancestors of contemporary Semitic speaking groups of Ethiopia somewhere in the Sahara, noticeably more northward than their current habitat. However, even if one were to entertain a back-migration scenario as the causal factor for all African J1 clades for arguments sake, it appears to have arrived when the clades were in their very early stages of diversification, hence the abundance of paraphyletic clades, as discussed elsewhere here [link].

If the spread of the Neolithic farming subsistence played any role in all of this, then one would have to contend that it likely did not accompany some massive movement of people from the so-called "Near East", but rather, small scale migrations likely induced by increasing social organizations in both the so-called "Near East" and the Sahara, paving way to the opening of early and perhaps modest trade routes. This may have primarily involved fauna and possibly flora in the Neolithic context, between populations in each area with a view to liven up their preexisting stock with more choices or variety [with 'exotic' goods]. As such, would-be migrants who decided to settle in a new homeland, simply integrated into preexisting Saharan communities, and thereby not shifting the traditions of host communities in any considerable way.

We've already gone through the lack of immediacy between the so-called "Near Eastern" Neolithic farming "revolution" of economy therein, which is significant, considering that "Near Easterners" are right next door to the northeastern corner of Africa—one would expect entry into the Nile Valley through the Sinai corridor to have been more immediately accessible than many of the areas in mainland Europe, and hence, serve as one of the earliest entry points of demic-diffusion accompanying the spread of a tradition largely of a farming subsistence economy; several researchers claim that archaeological indicators suggest that large farming in northeastern Africa came in more or less about the same time as its spread into some areas in northern Europe, between ca. 8ky to 6ky ago or so, which makes it either on par and/or even later than certain southern areas of Europe. Yet, conversely, cattle domestication is said to have likely arrived before or about the same time as that in the so-called "Near East".

These developments don't square with massive intrusion of migrants into an area, thereby considerably shifting traditions in the destination point. It is against this backdrop that no considerable language shifts would have taken place either, which makes more sense in the Ethiopian context, considering the lack of tracing of "Near Eastern Neolithic-derived" terms in Ethio-Semitic languages. Now of course, the alternative to all this, is that hg J1 could have originated in the Sahara near the northeastern end of the African continent, and it certainly cannot be ruled out in the final analysis—just as the aforementioned matter of great internal diversity and paraphyletic clades demonstrate, but this is a matter that understandably doesn't sit well with many "westerners", just as the fact that E3b1a-M78 could be considered African ancestry [which if any, is usually begrudgingly accepted as African, preferably "northeast as opposed to sub-Saharan African"] and seeing as how both it and the J clade are widely acknowledged to be important markers of the diffusion of the so-called Neolithic farming subsistence into Europe.*

The argument revolving around the "Semitic" language family carries very little weight in the big scheme of things; it appears to be one that Lancaster heavily relies on. The Semitic language branch is after all, merely an offshoot of a language family that originated and spent the bulk of its evolution in Africa before spilling over to nearby territories.

Ethiopia has a distinction of being the most concentrated area for a fairly wide variety of a Semitic branch, which in this case, is what's deemed within "Western" academic circles as the south Semitic branch. When pressed on any justification for ruling out a possible direct African origin for the Semitic subphylum, Lancaster offered no specific or substantive explanation, other than to simply generalize that certain segments of "Western" academia profess a "Near Eastern" origin for the Semitic offshoot of the African language superphylum.

It is of note, that for all such speculation that Lancaster takes for granted as gospel truth, not one of these proponents have effectively demonstrated how [lexically and grammatically] and in what specific time frames Ethio-Semitic branch purportedly derived from the South Arabian branch. Sure, there are deemed to be some similarities here and there, which should be expected, given the history of bidirectional contact across the Red Sea, but this is far from establishing the particulars just mentioned, regarding time and nature of a purported derivation. Time can for example, be extrapolated from key root terms, with the aid of archaeology and other disciplines like bio-anthropology; examples of the sort, include proclaimed "Neolithic" terms. None has been identified, in the case of connections between Ethio-Semitic and known South Arabian dialects. As matter of example,

Andrew Lancaster writes:

But Lionel Bender (1997), a leading expert on Ethiopian languages, proposed a scenario upon linguistic grounds wherein Semitic languages originated in Ethiopia and crossed the Red Sea. We can note that although this linguistic theory would be in line with these very particular and unsurprising genetic links between the Horn of Africa and the Southern Arabian Peninsula, it does not correspond to much else in genetics or archaeology, and there is no reason to invoke such a theory in order to explain genetic links between the Horn of Africa and nearby Southern Arabia.

While Lancaster in his own little way seeks to downplay Bender's take on the geographic origin of Semitic, which in his very own words was proposed "upon linguistic grounds", by way of thereafter making references to its misplaced impact or implications on molecular genetics and archaeology that no specific personality had made in the first place, he provides no answers to the requested linguistic particulars just discussed above. His need to invoke Bender here, is to presumably discourage potential usage of Bender's proposal for the very thing that he admits is the case:

We can note that although this linguistic theory would be in line with these very particular and unsurprising genetic links between the Horn of Africa and the Southern Arabian Peninsula.

His real concern here, is that Bender's findings may be seized upon as yet another line of evidence that can be used to buttress an "African" origin point for E-M34, and its subsequent spilling over to nearby territories, as opposed to vice versa. That said, Lancaster's line of defense for not being able to substantively explain the nature and time-line of the genesis of a "Near Eastern" origin for the Semitic subphylum, culminating in Ethio-Semitic in the African Horn, is that he is not a professional linguist and has to rely on others; any clear-headed individual can see right through it as a dismissive line of defense, because if one is bold enough to take sides, then one ought to know the particulars of the arguments they are siding with. When pressed on it, Lancaster was not even able to offer further explanation for the immediately obvious loose ends that Chris Ehret et al's (2009) recent paper seem to be suffering from. The paper in question was: Bayesian phylogenetic analysis of Semitic languages identifies an Early Bronze Age origin of Semitic in the Near East, which itself is a noticeable departure from Ehret's own past viewpoints on the genesis of Semitic. Change of viewpoints is of course not unusual in academia, but it has to be accompanied with a well-defined intellectual justification, that is clearly laid out before the audience. The abstract put forward for the just-now-mentioned paper goes like this:

Kitchen A, Ehret C, Assefa S, Mulligan CJ. Department of Anthropology, PO Box 103610, University of Florida, Gainesville, FL 32610-3610, USA.

The evolution of languages provides a unique opportunity to study human population history. The origin of Semitic and the nature of dispersals by Semitic-speaking populations are of great importance to our understanding of the ancient history of the Middle East and Horn of Africa. Semitic populations are associated with the oldest written languages and urban civilizations in the region, which gave rise to some of the world's first major religious and literary traditions. In this study, we employ Bayesian computational phylogenetic techniques recently developed in evolutionary biology to analyse Semitic lexical data by modelling language evolution and explicitly testing alternative hypotheses of Semitic history. We implement a relaxed linguistic clock to date language divergences and use epigraphic evidence for the sampling dates of extinct Semitic languages to calibrate the rate of language evolution. Our statistical tests of alternative Semitic histories support an initial divergence of Akkadian from ancestral Semitic over competing hypotheses (e.g. an African origin of Semitic). We estimate an Early Bronze Age origin for Semitic approximately 5750 years ago in the Levant, and further propose that contemporary Ethiosemitic languages of Africa reflect a single introduction of early Ethiosemitic from southern Arabia approximately 2800 years ago. - abstract ends -

Supposing one were entertaining the authors' proposal, the 800 BC or so date, or even if one were to extend this date to the beginning of the south Arabian influences coinciding with the emergence of the the D'mt complex, logically suggests that any already differentiated and fully developed south Arabian "Semitic" language that diffused into the African Horn would have been adopted as is, meaning—in the very shape or form the language was brought in and expected to be no different, especially in the era it was introduced. However, from archaeology, and citing personal notes posted elsewhere:

"The inscriptions dating from this period in Ethiopia are apparently written in two languages, pure Sabaean and another language with certain aspects found later in Ge`ez (Schneider 1976). All the royal inscriptions are in this second, presumably Ethiopian, language." - Stuart Munro-Hay

What does this imply? "Pure" as used here, suggests that although "Epigraphic South Arabian" alphabets were used to convey a message in two different languages [one for south Arabian administrative centers, and the other for the comprehension of the locals (aka "Ethiopian" people, i.e. Eritreans, Tigrinya or what have you)], one of the languages on the inscriptions was the south Arabian language that was brought in along with South Arabian immigrants, while the other was a local language aka a local "Ethiopian" language.

Though both languages were written in ESA alphabets, evidence above suggests that the "Ethiopic" language very likely had grammatical features that clearly distinguished it from its Sabean/south Arabian counterpart. The aforementioned citation of Munro-Hay should be instructive, once again:

"...and another language with certain aspects found **later** in Ge`ez (Schneider 1976).

Now, Ge'ez is considered to be Semitic, which therefore follows that this ancestral language was the proto-Semitic language of Ge'ez.

Also, the era suggested in the abstract implies that the Neolithic J carriers of the region [Ethiopia, presumably migrants originally from South Arabia] didn't already speak some form of proto-Semitic or Semitic, but rather, that this only came into being around the time of the D'mt complex, give or take.

Now of course, the authors of the study at hand could attempt to move their dates and make it coincidental with these Neolithic era groups, but they would have to come up with a good deal of "south-Arabian" imported Neolithic root terms for the Ethio-Semitic branch, which hasn't been produced to date, that comes to attention, especially given that the Neolithic in the African Horn has been more linked to those of the Nile Valley in the Sudanese region, in terms of influences, than those in the Levant or south Arabia as sources of inspiration.

Furthermore, we are told:

"another language with certain aspects found later in Ge`ez (Schneider 1976). All the royal inscriptions are in this second, presumably Ethiopian, language." - Stuart Munro-Hay

The emphasized bit goes right back to the following, as already stated herein:

[One for south Arabian administrative centers, and the other for the comprehension of the locals (aka "Ethiopian" people, i.e. Eritreans, Tigrinya or what have you)], one of the languages on the inscriptions was the south Arabian language that was brought in along with South Arabian immigrants, while the other was a local language aka a local "Ethiopian" language.

If an observer takes issue with assigning "African origin" to E-M34 even as he/she professes to concede to an "Egyptian origin", then they are most surely suffering from the same psychologically-seated self-contradictions as Mr. Lancaster. It found expression in his debate etiquette, which visibly devolved for the worse, bordering juvenile at times as he sought to threw in off-topic distractions and playing the role of multiple personalities—doubling as a regular poster under his regular or actual name, and suspiciously, as "a moderator" with a pseudonym who only appears when the heat is being turned on Lancaster, as his viewpoint is put through its paces. It is not that Lancaster does not see a very compelling argument for E-M34 as essentially an African marker or lineage, it is just that he stigmatizes "Africa" and turns anything rightfully associated with it into something offensive [to him]. Presents a dilemma? Far from it; an African origin of E-M34 is more than compelling!

As regularly advised on this site, lookout for future updates.
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References*

— As noted in the body of the passages above.

— The passage placed in between two ' * ' signs was borrowed from a later posting [link] than the present one, because of its relevance to the discussion at hand.

—Semino et al. (2004), Origin, diffusion, and differentiation of Y-chromosome haplogroups E and J: inferences on the neolithization of Europe and later migratory events in the Mediterranean area.

—Cruciani et al. (2004), Phylogeographic Analysis of Haplogroup E3b (E-M215) Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa.

—J.R. Luis et al. (2004), The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations.

—Cadenas et al. (2007), Y-chromosome diversity characterizes the Gulf of Oman.

—*Personal notes taken from notes dated to 2009 and 2010.