https://science.sciencemag.org/content/350/6262/820.full
Ancient Ethiopian genome reveals extensive Eurasian admixture in Eastern Africa
So I didn't know about this "back flow" after farming - back down into East Africa?
"Nowadays, the highest genetic diversity of haplogroup E1b1b is observed in Northeast Africa, especially in Ethiopia and Somalia, which also have the monopoly of older and rarer branches like M281, V6 or V92. This suggests that E1b1b may indeed have appeared in East Africa, then expanded north until the Levant"
https://www.eupedia.com/europe/Haplogroup_E1b1b_Y-DNA.shtml
The erroneous claim was that the "back flow" was from 24,000 years ago. But it's much more recent.In Somali males, 14 haplogroups were identified. The frequency of the
clade E3b was 81.1%, including 77.6% of the haplogroup E3b1 defined by
the M78 mutation. The Eurasian haplogroup K2 was found in 10.4%, and
3.0% of the Somali Y chromosomes belonged to the major clade J.
So strangely this back flow appeared to happen via BOAT from Sardinia!
split into two branches separated by the geographic barrier of the
Mediterranean Sea, would explain this geographic pattern. However, the
absence of E-V68* and E-V257* in the Middle East (Table S2) makes a maritime spread between northern Africa and southern Europe a more plausible hypothesis.
Oops! https://www.biorxiv.org/content/10.1101/059311v1.full.pdf
Migrations from the Near East also occurred towards the southwest into East African populations which experienced West Eurasian admixture ~1,000 BCE32,33. Previously, the West Eurasian population known to be the best proxy for this ancestry was present-day Sardinians33, who resemble Neolithic Europeans genetically13,34. However, our analysis shows that East African ancestry is significantly better modelled by Levantine early farmers than by Anatolian or early European farmers, implying that the spread of this ancestry to East Africa was not from the same group that spread Near Eastern ancestry into Europe (Extended 283 Data Fig. 4; Supplementary Information, section 8).
Interestingly, archaeological evidence dates the arrival of Near Eastern domesticates (such as wheat, barley, and lentils) to the same time period (~3000 years ago) (13, 14), suggesting that the direct descendants of the farmers that earlier brought agriculture into Europe may have also played a role in the development of new forms of food production in the Horn of Africa."https://science.sciencemag.org/content/350/6262/820.full
Populations in the Horn of Africa (HOA: Ethiopia, Eritrea, Djibouti, and Somalia) have substantial non-African ancestry [11]–[15].
The most recent genomic studies estimate 30–50% non-African ancestry in
the Cushitic and Semitic speaking populations of the HOA resulting
primarily from admixture around 3 ka [16], [17]. This timeframe corresponds to the estimated time of origin of the Ethiosemitic languages [18]
and there are some carved inscriptions in South Arabian scripts
associated with temple ruins and ritual items in South Arabian styles
dated to the early first millennium BCE in the north Ethiopian highlands
[19]–[23].
These linguistic and archaeological connections have been cited in the
recent population genomic studies to support a hypothesis of high levels
of non-African migration into the HOA around 3 ka.
So I actually learned about the indigenous language of ethiopia from an Eritrean friend of mine - and when I told other younger Ethiopians, they were shocked that I knew the name of their indigenous language.
the majority are written in indigenous proto-Ge'ez [24].
the expansion south of E-M78 could have introduced non-African ancestry into the HOA [horn of africa] prior to 6 ka.
Early Back-to-Africa Migration into the Horn of Africa
In Somalis, the Time to Most Recent Common Ancestor (TMRCA) was estimated to be 4000–5000 years (2,500 BCE) for the haplogroup E-M78 cluster γ and 2100–2200 years (150 BCE) for Somali T-M184 bearers.[136]
Deep subclade E-Y18629 is commonly found in Somalis and has a formation date of 3,700 YBP (years before present) and a TMRCA of 3,300 YBP.[231]
A Somali schoolgirl.
According to mtDNA studies by Holden (2005) and Richards et al. (2006), a significant proportion of the maternal lineages of Somalis consists of the M1 haplogroup at a rate of over 20%.[232][233] This mitochondrial clade is common among Ethiopians and North Africans, particularly Egyptians and Algerians.[234][235] M1 is believed to have originated in Asia,[236] where its parent M clade represents the majority of mtDNA lineages.[237] This haplogroup is also thought to possibly correlate with the Afro-Asiatic language family:[233] In addition, Somalis, and other Horn African populations, also carry a significant rate of maternal L lineages associated with sub-Saharan Africa.
https://en.wikipedia.org/wiki/Somalis#Genetics
M1 back-migrated along with U6 in the late palaeolithic and mainly stayed in North Africa for a long time (probably small Oases or the Northern Nile area) and only re-entered the Horn post-Holocene. It is positively correlated with North African or West Eurasian autosomal ancestry rather than with Sub-Saharan ancestry.
https://www.somalispot.com/threads/nilote-east-african-and-natufian-mena.55817/page-3
right.
Haplogroup E did indeed originate in West Asia, not in Africa. Btw, West Africans also carry archaic non-homo sapien admixture too at much higher rates than Euros & Asians carrying Neanderthal admixture. Furthermore, the E haplogroup was exclusively carried by Ancient Afro-Asiatic people only.
The false notion that the E haplogroup originated in Africa is afrocentric garbage...
oops! So really?
However, Cruciani et al. 2007 were able to study more data, including populations from North Africa who were not represented in the Semino et al. 2004 study, and found evidence that the E-M78 lineages which make up a significant proportion of some populations in that region, were relatively young branches (see E-V32 below). They therefore concluded that "Northeast Africa" was the likely place of origin of E-M78 based on "the peripheral geographic distribution of the most derived subhaplogroups with respect to northeastern Africa, as well as the results of quantitative analysis of UEP and microsatellite diversity". So according to Cruciani et al. 2007 E-M35, the parent clade of E-M78, originated in East Africa, subsequently spread to Northeast Africa, and then there was a "back migration" of E-M215 chromosomes that had acquired the E-M78 mutation. Cruciani et al. 2007 therefore note this as evidence for "a corridor for bidirectional migrations" between Northeast Africa (Egypt and Libya in their data) on the one hand and East Africa on the other. The authors believe there were "at least 2 episodes between 23.9–17.3 ky and 18.0–5.9 ky ago".
ok.... so.... that starts to clarify things...
Fourth, a unique East African lactase persistence allele is found at its highest frequency in the Maasai [75] who have about 21% Ethio-Somali ancestry (Table S5). This lactase persistence allele is different from the alleles associated with lactase persistence in Europe [76], [77] or Arabia [78], [79], and likely arose during the last 7,000 years [75]. The Maasai do not have the Arabian lactase persistence allele, which is estimated to have originated about 4,000 years ago (95% CI: 250–27,575) and is present at high frequencies in Arabian populations (>50%) [78], [79]. This Arabian allele is also almost absent in the Somali (1.6%) [79], which further supports our hypothesis that gene flow from Arabia within the last few thousand years cannot explain the non-African ancestry in HOA populations.
that the Ethio-Somali IAC is estimated to have diverged from all other non-African IACs by at least 23 ka; and that the Ethio-Somali IAC does not contain the unique Arabian lactase persistence allele that arose about 4 ka. In combination, these data suggest that the Ethio-Somali ancestors admixed with African-origin HOA ancestors sometime after 23 ka, but before the Middle Eastern admixture during the last few thousand years.
we argue that the non-African origin Ethio-Somali ancestry in the HOA is most likely pre-agricultural.
We hypothesize that a population with substantial Ethio-Somali ancestry could be the proto-Afro-Asiatic speakers. A later migration of a subset of this population back to the Levant before 6 ka would account for a Levantine origin of the Semitic languages [18] and the relatively even distribution of around 7% Ethio-Somali ancestry in all sampled Levantine populations (Table S6).
Later migration from Arabia into the HOA beginning around 3 ka would explain the origin of the Ethiosemitic languages at this time [18], the presence of greater Arabian and Eurasian ancestry in the Semitic speaking populations of the HOA (Table 2, S6), and ROLLOFF/ALDER estimates of admixture in HOA populations between 1–5 ka (Table 1).
https://genome.cshlp.org/content/26/2/151.short
These results place indigenous Arabs as the most distant relatives of all other contemporary non-Africans and identify these people as direct descendants of the first Eurasian populations established by the out-of-Africa migrations.
https://www.cell.com/cell/pdf/S0092-8674(20)30487-6.pdf
The results show that since the Bronze Age, an additional East-African-related component was added to the region average10.6%,... Bronze Age Southern Levant
We also see an Eastern-African-related ancestry entering the region after the Bronze Age with an approximate south-to-north gradient.
May 2020
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