One other (seemingly important) observation is that the (OOA) ancestry/origin (apparently all or the the vast majority) in modern Eurasians dates from the approximately 70 ka BC wave (the second major wave) of migration of modern humans from Africa, and not from an earlier one dating to 125 ka BC ., as the authors seem to suggest (which instead seems to have left little to no legacy in modern Eurasians overall). Much less (it would seems to me) would said earlier migration (with generally little to no autosomal legacy) be likely to be the source of such major/dominant modern Eurasian uni-parental lineages (as the paper discuses)—particularly when concerning the maternal lineages ancestral to all/nearly all those of living Eurasian populations.
The divergence and expansion of L3 (around 70,000 years ago) is associated with the expansion of (a segment/subgroup of modern humans in Africa) the ancestors of non-African modern humans out of Eastern Africa into Eurasia (which also occurred around 70,000 years ago), and also with a similar expansion within Africa/to other parts of Africa from the East of the continent
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Another significant issue with Cabrera’s theory:
He argues that the lack of relative lack of mtdna M in the levant (and its greater abundance in deeper rootedness further toward South East Asia an Oceania (rather than nearer to Africa), as well as the south East Asian base of N, is evidence that they (M and N) did not originate near Africa, and therefore that its ancestor L3 did not originate in Africa but somewhere closer to Asia. However, the lack of basal M in current populations near Africa (such as the Levant), seems more likely due to later migrations within Western Eurasia, which could easily obscure the original earlier paleolithic distribution of lineages. As commenter Lank explained:
“The correlation between Y-DNA DE and mtDNA L3 in Africa has been obvious for many years. There is no a priori reason to assume Y-DNA DE originates outside Africa, especially when it has roughly the same age as mtDNA L3 (although, if it was part of a back migration, it certainly would have brought some mtDNA L3). There was mtDNA M and even pre-N, as well as a lot of Y-DNA C even in Paleolithic Europe, so the modern concentration of Y-DNA/mtDNA diversity in eastern rather than western parts of Eurasia is not representative of the distribution going back tens of thousands of years.”
Also, the makeup of Western Eurasia (and some degree India) greatly changed during prehistory due to the back-migrations of more northerly Eurasians, in waves between the late paleo-lithic/mesolithic and neolithic—(who were likely of "proto-caucasoid" type) into South West Asia (including the Levant and Near East)—whose ancestry is now dominant in those areas, largely replacing the earlier inhabitants (directly descended from the first 70 ka bc OOA settlers of those regions (who would have been closer to a proto-Oceanic or so called proto-Austaloid type).
The descendants of the earlier modern human inhabitants of South Eurasia survive only in mixed form in India (the ASI/ancestral South Indian component, which is always to some degree hybridized with the more N. W. Eurasian/early "caucasoid"-related ANI component), and sometimes in less mixed form in Oceania and a few parts of South East Eurasia (as Negritos, Andamanese, Melanesians, Papuans, Australians, etc), some of which populations may preserve some more basal Eurasian lineages lost closer to Western Eurasia due to later migration and population replacement.
Also, perhaps somewhat importantly, M is also found in the horn of Africa—Somalia and Ethiopia, and at low levels in the Maghreb. And in those places is considered to come from a paleolithic migration from S.W. Eurasia into N. E. Africa and the horn (which indicates that early M once existed in early South West Eurasia; in Arabia and/or the Levant, before later population movements)
A somewhat similar back-migration of more northern Eurasians occurred in the South East of Eurasia involving the swamping of the S.E. Asian Negritos in many areas by what would termed proto-mongoloids/early Eastern Eurasians (who/a cluster or cline that likely originated from South China, North Thailand, or some where between that region and the south Himalayas such as N. E. Myanmar/Burma) in the neolithic period.
It seems more likely that the originally East African L3 left Africa, split into M (in South West Asia, perhaps near Arabia or the Near East), and into N perhaps closer to South Asia/India or East India bordering S. E Asia. And that much M/more basal M in West Eurasia, the Middle East, and parts of West India (and N in West Asia and the Indian subcontinent), was replaced (with more derived/less basal lineages—less basal than those that had survived in places like Australasia) by later more northern-derived populations.
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Another thing I like to mention here. We have seen racist online rhetoric buzz words come alive on a academic level with in recent years. This paper is just one of them. This of course is not by coincidence, but more so by design.
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
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quote:Originally posted by Elmaestro: Its hard to assign a haplogroups origins to somewhere where there's no basal/unique clades. Theres no E* lineages that are found only outside of Africa. for example E1a branched off earlier than E1b1... I'd likely branch off closer to the original location of E1. E2 is somewhat exclusively African aswell and so forth.
The same thing is applied to Mt.Haplogroups L0* and Yhap A0* ...both are the most basal Uniparental haps. Where are the daughters found uniquely?
quote:
Of the clades resulting from the four deepest branching events, all but one are exclusive to Africa, and the TMRCA of all non-African lineages (that is, the TMRCA of haplogroups DE and CF) is ~76,000 years (Fig. 1, Supplementary Figs. 18 and 19, Supplementary Table 10, and Supplementary Note). We saw a notable increase in the number of lineages outside Africa ~50–55 kya, perhaps reflecting the geographical expansion and differentiation of Eurasian popula- tions as they settled the vast expanse of these continents. Consistent with previous proposals a parsimonious interpretation of the phylogeny is that the predominant African haplogroup, haplogroup E, arose outside the continent. This model of geographical segregation within the CT clade requires just one continental haplogroup exchange (E to Africa), rather than three (D, C, and F out of Africa). Furthermore, the timing of this putative return to Africa—between the emergence of haplogroup E and its differentiation within Africa by 58 kya—is consistent with proposals, based on non–Y chro- mosome data, of abundant gene flow between Africa and nearby regions of Asia 50–80 kya15.
Punctuated bursts in human male demography inferred from 1,244 worldwide Y-chromosome sequences G David Poznik, Yali Xue 2016
quote: "haplogroup CF and DE molecular ancestors first evolved inside Africa and subsequently contributed as Y chromosome founders to pioneering migrations that successfully colonized Asia. While not proof, the DE and CF bifurcation (Figure 8d ) is consistent with independent colonization impulses possibly occurring in a short time interval."
--Peter A. Underhill , Toomas Kivisild - 2007
Use of Y Chromosome and Mitochondrial DNA Population Structure in Tracing Human Migrations
quote:“The Y chromosome Alu polymorphism (YAP, also called M1) defines the deep-rooted haplogroup D/E of the global Y-chromosome phylogeny [1]. This D/E haplogroup is further branched into three sub-haplogroups DE*, D and E (Figure 1). The distribution of the D/E haplogroup is highly regional, and the three subgroups are geographically restricted to certain areas, therefore informative in tracing human prehistory (Table 1). The sub-haplogroup DE*, presumably the most ancient lineage of the D/E haplogroup was only found in Africans from Nigeria [2], supporting the "Out of Africa" hypothesis about modern human origin. The sub-haplogroup E (E-M40), defined by M40/SRY4064 and M96, was also suggested originated in Africa [3-6], and later dispersed to Middle East and Europe about 20,000 years ago [3,4]. Interestingly, the sub-haplogroup D defined by M174 (D-M174) is East Asian specific with abundant appearance in Tibetan and Japanese (30–40%), but rare in most of other East Asian populations and populations from regions bordering East Asia (Central Asia, North Asia and Middle East) (usually less than 5%) [5-7]. Under D-M174, Japanese belongs to a separate sub-lineage defined by several mutations (e.g. M55, M57 and M64 etc.), which is different from those in Tibetans implicating relatively deep divergence between them [1]. The fragmented distribution of D-M174 in East Asia seems not consistent with the pattern of other East Asian specific lineages, i.e. O3-M122, O1-M119 and O2-M95 under haplogroup O [8,9].”
--Hong Shi et al.
Y chromosome evidence of earliest modern human settlement in East Asia and multiple origins of Tibetan and Japanese populations
quote:The regional distribution of an ancient Y-chromosome haplogroup C-M130 (Hg C) in Asia provides an ideal tool of dissecting prehistoric migration events. We identified 465 Hg C individuals out of 4284 males from 140 East and Southeast Asian populations. We genotyped these Hg C individuals using 12 Y-chromosome biallelic markers and 8 commonly used Y-short tandem repeats (Y-STRs), and performed phylogeographic analysis in combination with the published data. The results show that most of the Hg C subhaplogroups have distinct geographical distribution and have undergone long-time isolation, although Hg C individuals are distributed widely across Eurasia. Furthermore, a general south-to-north and east-to-west cline of Y-STR diversity is observed with the highest diversity in Southeast Asia. The phylogeographic distribution pattern of Hg C supports a single coastal 'Out-of-Africa' route by way of the Indian subcontinent, which eventually led to the early settlement of modern humans in mainland Southeast Asia. The northward expansion of Hg C in East Asia started approximately 40 thousand of years ago (KYA) along the coastline of mainland China and reached Siberia approximately 15 KYA and finally made its way to the Americas.
--Zhong H1, Shi H, Qi XB, Xiao CJ, Jin L, Ma RZ, Su B.
Global distribution of Y-chromosome haplogroup C reveals the prehistoric migration routes of African exodus and early settlement in East Asia.
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
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quote:Originally posted by Oshun: So... many of those "true negro" West Africans were Asiatics?
wikipedia, L3
quote:
L3 is common in Northeast Africa, in contrast to others parts of Africa where the haplogroups L1 and L2 represent two thirds of mtDNAs. L3 sublineages are also frequent in the Arabian peninsula.
According to Maca-Meyer et al. (2001), "L3 is more related to Eurasian haplogroups than to the most divergent African clusters L1 and L2". L3 is the haplogroup from which all modern humans outside Africa derive.
It’s quite amazing when you think about, isn’t it?
quote:The Bambara & Madinka 40% L3 Lineage
Mitochondrial DNA Variation in Mauritania and Mali and their Genetic Relationship to Other Western Africa Populations
Table 2) was detected in Mali. Although it shares the HVI 222 transition with other North African sequences belonging to haplogroup H (Rando et al. 1998), the RFLP analysis placed it in the basal HV cluster. Surprisingly for a western Africa country, around 42% of the sub-Saharan African sequences were L3 lineages. The predominant haplogroups belonged to L3b (17%), L3e (13%) and L3d (8%), but with different distribution within ethnolinguistc groups. Whereas the Bambara have higher frequencies of L3b (21%) and L3e (10%), L3d (10%) is similar in both samples
~González AM Mitochondrial DNA variation in Mauritania and Mali and their genetic relationship to other Western Africa populations. https://www.ncbi.nlm.nih.gov/pubmed/16907709
quote:Within the human mitochondrial DNA (mtDNA) tree, haplogroup L3 encompasses not only many sub-Saharan Africans but also all ancient non-African lineages, and its age therefore provides an upper bound for the dispersal out of Africa. An analysis of 369 complete African L3 sequences places this maximum at ∼70 ka, virtually ruling out a successful exit before 74 ka, the date of the Toba volcanic supereruption in Sumatra.
[…]
The L3 mtDNA pool within Africa suggests a migration from Eastern Africa to Central Africa ∼60 to 35 ka and major migrations in the immediate postglacial again linked to climate. The largest population size increase seen in the L3 data is 3–4 ka in Central Africa, corresponding to Bantu expansions, leading diverse L3 lineages to spread into Eastern and Southern Africa in the last 3–2 ka.
~Pedro Soares et al. The Expansion of mtDNA Haplogroup L3 within and out of Africa Molecular Biology and Evolution, Volume 29, Issue 3, 1 March 2012, Pages 915–927
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Not reading the thread, but I'd say back migration occurred when Papuans made sago palm flour, leaving the large rind, which was a bark canoe, and then began paddling (not yet sailing) along currents to Australia, East Indonesia, Sri Lanka (45ka monkey bones used as arrowheads) and further westward.
quote:Mitochondrial DNA (mtDNA) haplogroup L2 originated in Western Africa but is nowadays spread across the entire continent.
MtDNA haplogroup L2 is the sister branch of the Eastern African L3′4′6 clade that contains all the OOA diversity within haplogroup L3. While L3′4′6 originated in Eastern Africa22, haplogroup L2 probably originated in Western Africa but is nowadays widespread across the continent; it is highly frequent in many regions, such as in Western/Central and Southeast Africa (probably associated with the Bantu expansion that occurred in the last few millennia) and in Northwest, most likely due to trans-Saharan slave trade18, 25.
Together with haplogroup L3, it represents ~70% of sub-Saharan mtDNA variation but despite its high frequency and wide distribution, L2 was not involved in the OOA 26, since most likely it was not yet arrived in Eastern Africa by that time.
The demographic history of L2 is not yet completely understood, especially concerning the age of the expansion into Eastern Africa, a region that might have acted as a refuge during some severe episodes of climate oscillations over the last hundred thousand years27. One possibility is that the expansion of L2 to the East, most likely as with the expansion to the South, was related with movements of Bantu-speaking populations. However, in the regions of highest frequency of L2 in Eastern Africa (over 30%, in the area of Sudan and Ethiopia)13 there are no records of Bantu groups. Furthermore, recent evidence from HVS-I13 suggests that this haplogroup might have first expanded to Eastern Africa much earlier, possibly due to the improvement of climate conditions during the early Holocene. This signal was also observed with Bayesian analysis of L2 (and L2a) complete sequences28. Moreover, particular clades of L2a and L2c suggest an expansion, possibly along the Sahel corridor, after the LGM18. Migrations at this time frame are also observed in branches of other African haplogroups, such as L0a, L1b and L3f2, 12, 18, 29.
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