It is common to distinguish between Africans and non-Africans, with the former being much more genetically diverse than the latter. But, the real "gap" in human origins seems to be between the really old Africans ("Paleoafricans") and the rest ("Afrasians").Now, a new paper has come along that provides further support for the ancient split among humans in Africa, and its more recent "healing".
The Paleoafrican element is entirely confined to Africa, while the Afrasian one is found in both Africa and Eurasia. Indeed, modern humans can be entirely split into two groups: (i) a group of "pure" Afrasians which includes all non-Africans, and (ii) a group of Afrasian-Paleoafricans which includes all non-Caucasoid Africans. Human groups of entirely Paleoafrican origin, unhybridized with the younger Afrasians are no longer in existence.
The Afrasians are a recent branch of humankind, and one which was for a great length of time separated reproductively from the Paleoafricans. This accounts for the reduced genetic diversity of Eurasians who are descended entirely from the Afrasian branch; by contrast, Sub-Saharan Africans and East Africans are the result of the intermixture of the Afrasians with the Paleoafricans, and this accounts for the high genetic diversity and antiquity of these populations.
The BBC has a story on this.
Ancient humans started down the path of evolving into two separate species before merging back into a single population, a genetic study suggests.The American Journal of Human Genetics doi:10.1016/j.ajhg.2008.04.002
The genetic split in Africa resulted in distinct populations that lived in isolation for as much as 100,000 years, the scientists say.
...
"We don't know how long it takes for hominids to fission off into separate species, but clearly they were separated for a very long time," said Dr Spencer Wells, director of the Genographic Project."They came back together again during the Late Stone Age - driven by population expansion."
...Dr Wells told BBC News: "Once this population reached southern Africa, it was cut off from the eastern African population by these drought events which were on the route between them."
Modern humans are often presumed to have originated in East Africa and then spread out to populate other areas. But the data could equally support an origin in southern Africa followed by a migration to East and West Africa.
The genetic data show that populations came back together as a single, pan-African population about 40,000 years ago.
This renewed contact appears to coincide with the development of more advanced stone tool technology and may have been helped by more favourable environmental conditions.
"[The mixing] was two-way to a certain extent, but the majority of mitochondrial lineages seem to have come from north-eastern Africa down to the south," said Spencer Wells.
The Dawn of Human Matrilineal Diversity
Doron M. Behar et al.
Abstract
The quest to explain demographic history during the early part of human evolution has been limited because of the scarce paleoanthropological record from the Middle Stone Age. To shed light on the structure of the mitochondrial DNA (mtDNA) phylogeny at the dawn of Homo sapiens, we constructed a matrilineal tree composed of 624 complete mtDNA genomes from sub-Saharan Hg L lineages. We paid particular attention to the Khoi and San (Khoisan) people of South Africa because they are considered to be a unique relic of hunter-gatherer lifestyle and to carry paternal and maternal lineages belonging to the deepest clades known among modern humans. Both the tree phylogeny and coalescence calculations suggest that Khoisan matrilineal ancestry diverged from the rest of the human mtDNA pool 90,000-150,000 years before present (ybp) and that at least five additional, currently extant maternal lineages existed during this period in parallel. Furthermore, we estimate that a minimum of 40 other evolutionarily successful lineages flourished in sub-Saharan Africa during the period of modern human dispersal out of Africa approximately 60,00070,000 ybp. Only much later, at the beginning of the Late Stone Age, about 40,000 ybp, did introgression of additional lineages occur into the Khoisan mtDNA pool. This process was further accelerated during the recent Bantu expansions. Our results suggest that the early settlement of humans in Africa was already matrilineally structured and involved small, separately evolving isolated populations.
Link
It would have been better before we jump into conclusions to have some paleo-anthropological evidence for the specific theory as well.
ReplyDeleteOr at least some archaeological clues!
I never claimed that the Palaeoafricans were a homogeneous group, stating clearly that they included both Khoi-san and pygmies; what this paper has done is identify one, the oldest population of Palaeoafricans, i.e., the Khoi-San or Capoids. The authors make it clear that there were other instances of genetic isolation in Africa:
ReplyDelete"The proposed matrilineal sequestration of African MSA mtDNA into isolated populations does not seem to be restricted to Khoisan. A recent study showed that ancestors of contemporary Pygmies diverged from an ancestral Central African population no more than 70,000 ybp and that isolation was breached throughout the LSA.16 Moreover, this matrilineal sequestration pattern also offers a simple explanation to the surprising finding that of the more than 40 mtDNA lineages in Africa at the time modern humans left Africa3 ( Supplemental Data), only two of the variants, (L3)M and (L3)N,4 gave rise to the entire wealth of mtDNA diversity outside of Africa."
So, you see the fact that only M/N are found a Eurasians is not an accident of only these two lineages migrating out of Africa, but a consequence of the fact that there was genetic division within Africa at different time scales and involving different peoples.
Also, note that we were lucky to be able to sample the Khoi-san and pygmies, because they continue to exist as separate identifiable populations up to this day. There are doubtlessly other, assimilated, Palaeoafrican elements in Africa that remain discovery.
This L3 population of paleolithic central/north eastern africa (with prely african origins) can like your qouted evidence says, be split into 2 groups.
ReplyDelete1 group would colonize the middle east, europe, North africa, east asia and the americas.
the other would colonize oceania, australia and in a minority colonize parts of present day middle eastern populations and present day east asian and even indigenous american populations.
That's not supported by any genetic study so far, AFAIK. Eurasians are very homogenous in comparison to Africans, of which they are a subset (a subset of a subset, actually). The main difference inside L3 populations is between those who remained in Africa (eventually mixing with other Africans) and those who migrated to Asia (and from there to the rest of the planet).
If you are thinking in terms of the apparent M/N dicothomy, the fact is that it does not correspond with your geographical distribuion either and it's likely that both groups were represented among the original colonists of Asia before they spread around. Even it's quite probable that R (subclade of N) was there before the colonist populaton began to split somewhwere around the Arabian Sea or in India.
I think there's a higher level of information in this comments section than I found in my whole first year of anthropology courses. You guys have a talent for boiling things down to what's important.
ReplyDeleteDienekesp, I think you're theory on Afrasians and Paleoafricans is correct.
P. Squiggles, you wrote: "Anthropoligical evidence shows us that negroids and nitolids didnt exist until recently and the africans around 100,000 years ago were probably of a robust and archaic proto australoid form."
So the khoi-san split came before the developement of this proto australoid form? Would the gracile khoi-san phenotype be derived or conserved?
---Kosmo
Is this "paleoafrican" term something really commonly used, or something made up to emphazise the separation of the khoisan lineage?
ReplyDeleteI think it's inadequate, anyway. It's not like they are really "older" than other human populations of the present. Actually, if both the main branches splited from each other at the same time, both branches have the same age. If one branch is not being called "neoafrican", the other one would better be labeled geographically as well.
It's not like they are really "older" than other human populations of the present.
ReplyDeleteIt's a tautology that all present-day populations are equally old. What is meant by older is: possessing genetic variants that are older and/or having an older origin.
Maju wrote, "That's not supported by any genetic study so far". I'm not sure if his work has been discredited or not but Cavalli-Sforza's map of the first principal component of gene distribution around the world shows the primary division is between Australian Aborigines and the rest of the world. The oppposite extreme is widespread but centred on Africa, the Arabian peninsular and Europe. Central and Eastern Asia, along with America, suggest a mixture of the two extremes, perhaps a sort of hybrid.
ReplyDeleteUnfortunately I cannot find the map anywhere on the net but it appears in the book "History and Geography of Human Genes".
I would like to add that when we say humankind nowadays emerged from groups like "Paleo-Africans" and "Afrasians" we presuppose that there was no "non African" archaic admixture to moderns!!!
ReplyDeleteThat's not been proven yet. Until we have samples from the DNA (autosomal, Y-DNA, etc.) from many different Early Moderns through out the world we are risking ourselves to be presented like the oracle of Delphi!!!
Even among Neanderthals there are big differences (like in the possession of the FOXP2 gene) and we need many more researches about archaic modern DNA before we can come to a final verdict.
terryt wrote, "I'm not sure if his work has been discredited or not but Cavalli-Sforza's map of the first principal component of gene distribution around the world shows the primary division is between Australian Aborigines and the rest of the world. The oppposite extreme is widespread but centred on Africa, the Arabian peninsular and Europe. Central and Eastern Asia, along with America, suggest a mixture of the two extremes, perhaps a sort of hybrid."
ReplyDeleteI think Cavalli-Sforza's claim of Australian aborigines' being the most (autosomally) genetically divergent subgroup of extant humans is not necessarily incompatible with Dienekes' hypothesis of an ancient split between "Palaeo-Africans" and "Afrasians," with Australian aborigines belonging to the Afrasian branch.
The way I would reconcile these two hypotheses is by supposing that the Afrasian branch had already diverged into several subgroups (e.g. Australian, East Asian, European, etc.) prior to the occurrence of admixture between a group of Palaeo-Africans and a certain distinctive subgroup of the Afrasians.
The Afrasians who hybridized with the Palaeo-Africans to produce modern Sub-Saharan African populations were probably related most closely to modern Afro-Asiatic populations, such as Berbers, Jews, Egyptians and other Arabs. The Y-DNA of modern Sub-Saharans, which consists of haplogroups E, K2, R1b1*, and J1, is almost entirely derived from this "Afro-Asiatic" subgroup of the Afrasians, whereas the mtDNA of modern Sub-Saharan African populations, especially in western and southern Africa, is almost entirely derived from the Palaeo-African component of their ancestry.
In addition, I would have the Australian branch of the Afrasians diverging the earliest from the Afrasian stem, with the Proto-Caucasoids and Proto-Mongoloids remaining connected to each other even after the separation of the Australians.
ReplyDeleteLater, one subgroup of the non-Australian Afrasians migrated into Africa and mixed with Palaeo-Africans, and another subgroup of the non-Australian Afrasians migrated into New Guinea/Melanesia and mixed with the earlier Australoid inhabitants there. The aboriginal inhabitants of Australia, however, have received the least genetic input from the later "Caucasoid-Mongoloid" branch of the Afrasians, and are therefore the most autosomally divergent among extant human populations.
@Terryt:
ReplyDeleteMaju wrote, "That's not supported by any genetic study so far". I'm not sure if his work has been discredited or not but Cavalli-Sforza's map of the first principal component of gene distribution around the world shows the primary division is between Australian Aborigines and the rest of the world.
What I've read of Cavalli-Sforza (1996, 1997) is coincident with the rest in placing the oldest branching between Africans and Eurasians (including Australo-Papuans, that would make a third level branch).
Anyhow, C-S's work is quite old for the fast pace of genetics and, also, a too simplistic interpretation of PC analysis has been put under question once and again. After all, they aren't but complex mathematical abstractions.
"In addition, I would have the Australian branch of the Afrasians diverging the earliest from the Afrasian stem, with the Proto-Caucasoids and Proto-Mongoloids remaining connected to each other even after the separation of the Australians."
ReplyDeletePeople, have you ever read anything about the branching of human haplogroups? You mix up everything together in such a mess that it is comical. Yesterday I wrote a long response to all the fantasies presented here, but it was not posted due to some error and since it disappeared somewhere in the internet ether, I won't write it again.
But at least, I enjoyed the discovery of the secondary (Proto)Nilotic migration from South Africa. I thought that I would have to wait for such a breakthrough until mid 21st century, i.e. up to my pensionary age.
EDIT: e3a reaches frequencies of up to 100% in western and Central Africa.
ReplyDeleteHaplogroup E is also Caucasoid-Mongoloid (a subgroup of the Afrasians) in origin. Sub-Saharan Africans have significant admixture of Afrasian Y-DNA haplogroups (those haplogroups descended from haplogroup CT), but Afrasians, including the Berbers, do not have significant amounts of Palaeo-African haplogroups.
ReplyDeleteHaplogroup E3b (or any form of haplogroup E for that matter) is NOT Palaeo-African. It doesn't match the pattern of mtDNA found among Sub-Saharan Africans. The mtDNA of Sub-Saharan Africans indicates that their "original" Y-DNA (prior to the influx of Afrasian Y-DNA haplogroups) should have consisted entirely of haplogroups A and B, which now form only a small fraction of the Y-DNA of Sub-Saharan Africans, just as the original Native American Y-DNA (haplogroup Q) has been replaced in all but approximately 15% of Aleuts.
Haplogroup E3b is Afrasian (or Subsaharan African but not Khoi-sanid.
ReplyDeleteAll of the E* descendants are of subsaharan african origin, some would migrate to west, central and east africa (from east africa). One branch (e3b) would migrate to north africa and later into the balkans where they mixed with caucasoids who had been living there for at least 30,000 years. Over time the population in the balkans would become fully caucasoid (dinaric and alpine).
All E* descendants descend from the m168 y-chromosome, and its the afrasians that also descend from m168 on the y-chromosome.
On the y-chromosome, we can see evidence for 2 sets of Paleo Africans (not just one like the mtdna shows us).
Theres the m60 paleo africans of central africa (though they make up a minority there as e3a is very dominant, the Hadza tribe are an example of a pure group) and the m90 paleo africans of southern africa (khoi-san peoples).
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ReplyDelete"For instance, North African Berbers are 100% caucasoid, yet 80% of their Y-chromosome is E3b, which is of a seperate African origin to the caucasoid and mongoloid haplogroups that came from the middle east."
ReplyDeleteBut Berber mtDNA haplogroups are ca. 75% Caucasoid, aren't they? This nicely agrees with the ratio of Caucasoid:Subsaharan ancestry in Maghreb Berbers (80:20). MtDNA can tell you more than Y DNA, because it is not so prone to genetic drift.
And what about Y haplogroup E, it prevailed over all remaining L3 lineages in East Africa and spreaded to the Sahara during a relatively wet phase 50 000 years ago. When the Saharan plateau began to dissicate with the advance of a new Ice Age 27 500 years ago, its branches were torn apart on all sides of the Saharan desert - E3a (E3b1a) found refuge in the forests of West Central Africa and mixed with Pygmy women (from which modern African "blacks" come from), E3b (E1b1b) remained relatively unmixed in East Africa, but mixed with Caucasoid groups in North Africa (from which modern Berbers come from).
Haplogroup E is more closely related to haplogroup D, to which a very large fraction of Japanese and Tibetans belong, than it is related to the other subclades of haplogroup CT, which we seem to have agreed is the Y-DNA equivalent to Dienekes' "Afrasian" category. If you want to claim that haplogroup E has an African origin, then how would you explain the presence of haplogroup D in Tibet and Japan?
ReplyDeleteYou should check the data and conclusions of Luis et al. (2004) before concluding that haplogroup E is originally African. Luis et al. found haplogroup E1-M33 only among their Egyptian sample, haplogroup E3b was found at very high frequencies (over 30%) among some of their samples of Bantu-speaking Sub-Saharan Africans, and haplogroup E3a was found in as many as 8% of Arabs in Oman (this is on the southeastern coast of the Arabian Peninsula in Asia, not even in Africa!) as well as among Egyptians. The distinction between E3b and E3a is not nearly so clear-cut as some people would have you believe; I find it likely that both E3b and E3a are originally of "Asian" (or "Afrasian," as Dienekes would say) origin, although E3a obviously mixed heavily with Palaeo-African females to form modern West and Central African populations, and haplogroup E3b mixed with both Palaeo-African females (although to a lesser extent than E3a) and Palaeo-African males to form modern East African populations.
Haplogroups A and B are the only original Palaeo-African Y-DNA haplogroups. Obviously, even the Palaeo-Africans were not a homogeneous group; one group of them (the haplogroup B people) were more closely related to the founders of the Afrasian population than they were to the other group of Palaeo-Africans (the haplogroup A people).
"If you want to claim that haplogroup E has an African origin, then how would you explain the presence of haplogroup D in Tibet and Japan?"
ReplyDeleteAt least as easy as the presence of DE* in Nigeria. You should really study more about this topic.
@Dienekes, why do you keep claiming Afrasians no longer exist.
ReplyDeleteI said that pure Paleoafricans don't exist, not that Afrasians don't exist. Almost everyone outside Africa is a pure Afrasian according to my definition of the term.
"Human groups of entirely Paleoafrican origin, unhybridized with the younger Afrasians are no longer in existence."
war lord said, "At least as easy as the presence of DE* in Nigeria. You should really study more about this topic."
ReplyDeleteHaplogroup DE(xE) was found at a low frequency among some samples from Nigeria. So, what? That tells me about as much as the fact that haplogroups R1b1* and K2 have been found among some samples from Nigeria and Cameroon. It means nothing more than that the Afrasians who have admixed with Palaeo-Africans to form the modern populations of Nigeria contained haplogroup E3a, haplogroup DE(xE), haplogroup R1b1*, and haplogroup K2 Y-DNA. That does not prove that haplogroup DE, R1b1, or K2 has originated in Nigeria among the local Palaeolithic "Palaeo-African" population.
Also, please do not write with such a condescending tone. I could just as reasonably tell you to go and "study more about this topic," particularly the correlations between the phylogeny of extant human Y-DNA and mtDNA on the one hand and geography, physical anthropology, archaeology, linguistics, and ethnology on the other.
@Dienekes.
ReplyDeleteBut Afrasians exist in pure or near pure form in Sub-saharan Africa too, Many west and central african groups are pure afrasians.
@ebizur.
E3a is of African origin, E3b arose in Egypt 20,000 years ago, E* arose in Uganda around 60,000 years ago.
D arose around that region at a similar time too.
West Africans and Central Africans have Little Paleo African Admixture.
Are you trying to call Afrasians Caucasoid? Because These genetic lineages tell us nothing about phenotype, and phenotypical traits can move independantly of haplogroup ancestry due to selective pressures. Everyone is aware that hair and eye pigmenation can move independantly of ancestry, well every other trait and gene can do so aswell.
Also the Paleo African population never expanded north of the Equator, the Afrasians were the first homo-sapien inhabitants of Central and West africa. Any small percentages of Paleo African Elements present amonst modern west and central africans are most likely to bi-directional gene flow that alos gave way to small amounts of Afrasian genes amongst khoi-san peoples.
Afrasians originated in Eastern/north east Africa right on the boundary between the sahara when it was a savanna grassland, via a DIRECT African origin. And it was Afrasians that conqoured the rest of the world, not Paleo Africans.
But why call them Afrasians, they didnt just conqour Asia, but the whole world. And Afrasians originated in Africa from a direct African origin and can still be found in close to pure form in sub-saharan africa without any non african admixture aswell such as caucasoid.
No african group has stood 'racially still' since the neo africans left africa, so no african group is racially reprasentative of what the common ancestor of what all non africans looked like.
ReplyDeleteBecause africans have had environmental pressures to develop traits since people left africa.
So looking for Proto caucasoids, proto mongoloids or proto australoids in Africa is Pointeless.
All africans have progressed from any ancient starting points since people left africa.
The khoi-san are least likely to have progressed in terms of their traits due to their lack of haplgroup mutations indicating lack of population bottle necks.
But Australian Aborigines have also few haplogropu mutations since they left africa and have been very isolated too.
But traits can still evolve over much longer periods of time without the need for population bottlenecks (haplogroup mutations). This can be due to slow insitu evolution or gene flow from neighbouring populations followed by appropriate selective pressures.
"For instance, North African Berbers are 100% Caucasoid,"
ReplyDeleteThink you might want to adjust that statement a bit.
http://en.wikipedia.org/wiki/Berber_people#Genetic_evidence
Tauregs and Kabyles are definately not 100% Caucasoid.
Prof:
ReplyDeleteDienekes never said that Afrasians were Caucasoid.
http://dienekes.blogspot.com/2005/05/mitochondrial-time-depth-of-humanity.html
He said:
Significantly Paleoafrican:
1. Sanids
2. Pygmids
3. Negrids
Afrasian-Paleoafrican:
4. Aethiopids
Entirely Afrasian:
5. Australasids
6. Europids
7. Mongolids
As far as I can tell from the paper, Western and Central Africans are pure "Afrasians". The Pygmies are estimated to have diverged 70KYA, which is PART of the Late Stone Age expansion out of East Africa. West and Central Africans are "Pure" "Afrasians". A particular Med-centric point of view would have "Negroids" separated from East Africans and "Afrasians" as far away as possible, since this would solve the "'Negoird'-component-in-Meds" and "East-Africans-as-Meds" issues (I'm not saying Dienekes subscribes to that view.).
ReplyDeleteThat Central and Western Africa were never colonized prior to "Afrasians" makes sense in terms of archaeology, since South Africa is the only place besides East Africa to have turned out Sapiens and Sapiens-implying artifacts after East Africa but before Eurasia. Early Sapiens were probably beach-combers, as implied by East and South African finds, and never penetrated into Central and Western Africa prior to this "Afrasian" expansion.
As far as I can tell from the paper, Western and Central Africans are pure "Afrasians".
ReplyDeleteYou are equating "Afrasians" with the non-Khoisan element, which is not how I defined this term.
since South Africa is the only place besides East Africa to have turned out Sapiens and Sapiens-implying artifacts after East Africa but before Eurasia.
West and Central Africa do not have a climate conducive to the preservation of artifacts.
My desire is to find more clues about the other branches of our past.
ReplyDeleteThat is the various clades which have been lost and that existed between MtDNA Eve and 70000 BC.
You are equating "Afrasians" with the non-Khoisan element, which is not how I defined this term.
ReplyDeleteIf Eurasians are simply a sub-set of East Africans and West-Central Africans are also subsets, all parts of the Late Stone Age expansion, what definition of your "Afrasian" exists between the East African descendants and Eurasians?
Are you saying a second expansion occurred after this one, from E. Africa? What's your prove?
West and Central Africa do not have a climate conducive to the preservation of artifacts.
Central Africa?...
Not conducive to fossilization and preservation of bio-matter, but how can stone tools be affected by that? Do the rocks in West Africa disappear after a certain while?
I must largely agree with Ren: stone tools are not really affected by climatology and, anyhow, if you can find human and hominid fossils in tropical Asia, you could equally find them in West Africa, that is not anyhow that homogenously junglish (what about the Sahel, for instance?). Of course, research density matters too, certainly.
ReplyDeleteAnyhow, both mtDNA and Y-DNA genealogies seem to agree that A+L0 (Y-DNA+mtDNA) separated first, many tens of thousand years (or at least many more mutations) before B+(L1,L2,etc.) broke apart (if they actually did) from CR+L3. The term Afrasians can therefore be applied to all BR+L1 Humankind with good reason.
You can also apply it as Dienekes does, to Eurasians plus their closest relatives in Africa, but these are so mixed with the immediately previous branch (not so distant in time anyhow) that it's surely not worth it. If it's of any help, I'd suggest to use the term "proto-Eurasians" for this CR+L3 sub-branch of "Afrasians". All very arbitrary anyhow, I know.
Sanids are 80%+ Paleo African and only 20% Afrasian
ReplyDeleteNegroids are only 30-40% Paleo African and 70% Afrasian
Other Central African Groups are up to 100% Afrasian.
Ethiopids are irrelevant, as they have cacuacsoid afrasian admixture.
The tutsi are pure Afrasians without caucasoid admixture.
but htese are just haplogroups, and have nothing to do with traits.
It depends how you use the terms, Squiggles. The CR+M/N group is normally described as "Eurasian", not "Afrasian", though it can well be argued that Y-DNA E clade is more African than anything else.
ReplyDeleteWhen Dienekes titles this post as "more support for the Afrasian/Paleoafrican hypothesis" he is refering to a paper that emphasizes the dicothomy between the Khoisan typical genealogical "clan" (A+L0) and the rest. In this sense only the Khoisan group could be defined as "Paleoafrican", while all the rest should be "Afrasian". Of course, such nomenclature is somewhat arbitrary but using "Afrasian" to mean "Eurasian" or "proto-Eurasian" instead of all non-Khoisan, as the paper (and overall genetics) suggests, is specially arbitrary, meaningless and decontextualized.
Also I wonder what knid of restrictive use of the term "Negroid" are you refereing to. AFAIK, "Negroid" classically applies to all sud-Saharan Africans, except Khoisans and arguably Pygmies and/or Ethiopids. So no idea what are your "other Central African groups" that are not "Negroid". Tuaregs maybe? Pygmies? Kenyan whites?
Your percentages also look terribly arbitrary, bordering nonsense, and based on thin air (most likely Y-DNA alone). MtDNA should give you a more reliable picture of overall ancestry anywhere in the World probably and mtDNA-wise, sud-Saharan Africans are mostly on their own (even if L3, it's L3xM,N - except in The Horn). Even then, Y-DNA E, even if "proto-Eurasian" (CR) has a basically African distribution and should be considered African.
Again I suggest the following terms for the succesive branchings:
- Paleoafricans, or maybe better, Australafricans ("austral" = southern): A+L0
- Afrasians: YxA(BR)+ LxL0
- Proto-Eurasians: CR + L3
- Eurasians (properly): CRxE + M,N
Very few (approx. 5% or fewer) Australian aborigines descend from mtDNA haplogroup M. Nearly all of them belong to haplogroup N(xR).
ReplyDeleteThe minor amounts of haplogroup M and haplogroup R (the latter usually in the form of the subclade P, which is also found in New Guinea and Melanesia) that are found among Australian aborigines might be due to influence from the New Guinea-Melanesia region after the initial colonization of Australia by the majority of the ancestors of Australian aborigines.
In any case, as I have mentioned before, Y-DNA haplogroup C seems to correlate in most cases with (certain forms of) mtDNA haplogroup N(xR), Y-DNA haplogroup F correlates in most cases with mtDNA haplogroup R (and maybe also some forms of N(xR)), and Y-DNA haplogroup DE seems to have originally been correlated with mtDNA haplogroup M prior to some sort of "extinction" of Y-DNA DE in certain areas of mtDNA haplogroup M distribution (particularly India and East Asia).
The relative "progressiveness" of modern African Negroids in comparison to Australian aborigines (and perhaps some other Australasians) might be due to a greater degree of admixture of progressive Caucasoid-Mongoloid elements in the ancestry of the Negroids. The Sanids are definitely not progressive (they rather approach something like your "Proto-Australoids"), and Y-DNA and mtDNA testing have also shown the Sanids to possess the lowest percentage of markers of Proto-Eurasian origin (Y-DNA CT and mtDNA N & M).
If we look at higher resolution haplotypes, we can see lots of African SPECIFIC mutations on L3 aswell.
ReplyDelete@ Squiggles
ReplyDeleteYour lumping together caucasoids, mongoloids and australoids as Eurasians?
I am not on my own: the whole genticist community is doing that since at least the early 90s. It is a fact that Eurasians are a subgroup of Africans, actually a subgroup of a subgroup of a subgroup. It is the universally accepted genetic paradigm regarding Human genealogy.
If you have no idea, as it seems, you should better talk less and listen more.
Australoids are less progressive and more archaic than Negroids.
Progressiveness is quite an arbitrary deefinition: what is wrong with being for instance more prognathous or having the forehead slightly more inclined? I have it and I am still smarter than the vast majority of humans.
All those Jurassic ideas are basically a racist nonsense. I don't mean that well done anthropometry does not have any merit but that concepts such as "progresiveness" are really more than dubious (mostly aesthetic and hence subjective) and that classifying humans only on craniometry has some inherent flaws that are made evident in comments like this one of yours. Phenotypes are more plastic than genotypes.
The first people to leave africa did not resemble modern day middle easterners, they would have been proto australoids if anything.
The most widely accepted model is that there was a single out-of-Africa migration and that Australian Aborigins, Swedes, Bengalis, Koreans and Apaches are all equally descendant from that more or less small group and that's why we talk of them as "Eurasians". Australian and Papuan natives have been almost totally isolated since arriving there, while the rest had more opportunities for admixture and therefore maybe for phenotypic refinement. This was also the case in Africa probably.
We don't know exactly which were the phenotypes of the bunch that left Africa for Asia some 60 or 70 thousand years ago but we know that all non-Africans, (plus largely North Africans and Malgassys, and less so Horners) are descendant from them.
This whole mtdna and y-dna for defing percentages of races is drivel.
It only takes 1 person to enter a group and bring new genes and traits which can under go positive selection, and the group will morph into being more phenotypically similar to the group the foreigner originated from or just that induvidual foreigner.
Phenotypes may be affected by that (introgression), when the gene casuing that is really strongly adaptative (seemingly was the case with lactose-digesting gene in Britain), though, of course, it's much more likely to happen if the adapted intruders are many more than just one in a million.
But autosomal lineages are not really affected by that selective pressure (neutral non-recombinable markers). Males are more likely to cause such an impact via poliginy but what about mtDNA? If a man can, in some very extreme cases, have dozens or even hundreds of sons, a woman's ability to spread her mtDNA lineage is much more limited. In fact mtDNA tends to be older and more varigated almost everywhere. The only selective pressures that affect autosomal lineages are therefore elite dominance (power) and sexual selection (attractiveness).
Instead they can be subject to founder effects and drift. A marginated (not powerful, surely less attractive by the usual standards) group could migrate and found a new lineage that might well later on become very succesful, in different circumstances. That's founder effect. A very clear succesful founder effect is that of Eurasians, who begining as a small displaced African clan became 80% of Humankind.
No human population around the globe has stodd still phenotypically even in the last millenia.
Exactly! Evolution never stops (and phenotype is not only driven by genotype anyhow). Doesn't that contradict your previous claims?
ebizur wrote
ReplyDeleteY-DNA haplogroup C seems to correlate in most cases with (certain forms of) mtDNA haplogroup N(xR), Y-DNA haplogroup F correlates in most cases with mtDNA haplogroup R (and maybe also some forms of N(xR)), and Y-DNA haplogroup DE seems to have originally been correlated with mtDNA haplogroup M prior to some sort of "extinction" of Y-DNA DE in certain areas of mtDNA haplogroup M distribution (particularly India and East Asia).
extinction what extinction? nothing is proven.
Indian population : 1 billion (1000) million. half of them female. 500 female. more than half of them mtDNA M. 250 mil. with more ancient clades than any other place including Melanesia.
I agree Relatively Y haplo C presence is not as large as those numbers which provide ammunition for austro centrists and anti southern dispersal theorists. May be they are mutated as Y haplo CF-H which is again represented in huge numbers in India
Mt haplo N also found in Indian tribals. Out of female M+N group some advanced and some might have left behind.
C is with N only in Australia other places it is with M also.
I don't know how can you say C is with N and DE with M when you can see hundreds of millions of Indian (C-F(H)) + M .
Where as DE is nowhere found relatively.
The relative "progressiveness" of modern African Negroids in comparison to Australian aborigines (and perhaps some other Australasians) might be due to a greater degree of admixture of progressive Caucasoid-Mongoloid elements in the ancestry of the Negroids.
ReplyDeleteWhy? Where is that "Caucasoid-Mongoloid" element? You are not talking of typically African haplgroup E, are you? E has highest diversity in sudsaharan Africa and is without almost any doubt original from there.
As just said, progressiveness, is an arbitrary tag of basically aesthetical (subjective) value. If it has an intrinsecal (subconscious, not cultural) aesthetic value, it would only logical that all populations would have evolved in that direction due to sexual preferences, not because a bunch of hillybillies that decided to break apart and cross the sea in search of a desert beaches of their own suddenly happened to become magically the most beautiful and handsome people in the planet. If (some) Eurasians have eventually evolved towards a aesthetic direction (what is quite arguable), it is probably because of long term sexual selection and the immensity of their continent, that allowed for more varied choice of mates in some cases. Much of the same happened in Africa, that is not much smaller anyhow, but mostly separatedly.