by Phil78 1802 words
(1/22/20 Edit: Khoi-san populations are found to diverge around 200k in light of the Ballito results and their own in context of the modern Khoi-San.)
Many casual members of HBD may not be completely aware of the population history West Africans and hunter-gathers like Pygmies beyond, say, the Bantu Migration.
Those who frequent articles by population genetics bloggers such as Dienekes or Razib Khan ought to be aware of how, in the sense of Macro races, the two clusters are distinct despite their relatively close association in a human cladistic sense to the confusion of others.
Fortunately enough, two recent finds in both genes and fossils this year not only paint the history of these two groups but also humanity as a whole, with the evolutionary timeline of Sapiens being pushed back to 300k, possibly further according to Chris Springer.
Hublin–one of the study’s coauthors–notes that between 330,000 and 300,000 years ago, the Sahara was green and animals could range freely across it.
While the Moroccan fossils do look like modern H sapiens, they also still look a lot like pre-sapiens, and the matter is still up for debate. Paleoanthropologist Chris Stringer suggests that we should consider all of our ancestors after the Neanderthals split off to be Homo sapiens, which would make our species 500,000 years old. Others would undoubtedly prefer to use a more recent date, arguing that the physical and cultural differences between 500,000 year old humans and today’s people are too large to consider them one species.
(The morphological characteristics of these hominids will come into play latter.)
Taking in this information in, we now ought to have a better context to place the divergence of HG populations and the rest of mankind (including West Africans) being more than 260,000 years ago.
[Edit– Razib has recently posted a short piece recalling expert criticism on the reported date, suggesting that it is an overestimate. While quite possible, as he compares it to claims of a 25k split between European and NE asians and no neanderthal admixture in Europeans. With that said, he has also alludes to a similar suggestion on African lineages that I’ve outlined here. If this is the case, then why do they range so close to Modern West Africans? The reason, for the most part, being that this finding technically refers to it’s ancient primary cluster and not it’s modern composition as a whole.]
So in terms of proportions, 30% of the composition of West African people contain the human ancestors of the Ballito Boy, a specimen believed in turn to represent the ancestors of modern Khoisan people without the genetic admixture of either Bantu or East African Pastoralists. (Which this study finds to range from 9% to 22% in all modern Khoisan Groups).
[*Edit- When I say HG’s people association with West Africans, I’m referring to the relative position the two populations have compared the actual East African cluster exemplified the most by Nilotic people, not “Horners”. I realized this confusion when I look at genetic distance test and found Bushmen populations ranking closest to Ethiopians, this is probably just a result of their admixture with Ethiopians as later studies \accounted for the confound and gave more accurate results, West African’s closest cluster being both Nilotics and Ethiopians with Pygmies and San clustering closer than before, though Mbuti are rather intermediate with San than sharing a branch.
This seems to dampen earlier but plausible ideas suggestion of highland Ethiopians having a San-like African profile explain their affinity to each other, but this helps illustrate the nature of the cline in affinity of Native African clusters as Razib covered later that year both between each other and relative to non African populations. Here, we see that the San have closer affinities to West Africans than to Nilotics, though the pygmies groups having an odd relationship. Not only are Biaka people closer to West Africans than Mbuti are, but in general are closer to West Africans than to Mbuti. This is likely connected to these findings.
The findings also illustrate that oddly, next to my knowledge at least, how though the San and Mbuti share similarly deep splits from non-africans, both of their smallest distances are with the Biaka than with each other despite the Biaka being closest to West Africans who are as distant as the Mbuti are to the San. Clearly imagining pygmies as merely as a cline between San and Bantus doesn’t work without considering a either considering them their own cluster altogether or to isolation. I’m considering the former idea for the most part.
Mainly because Mbuti are the smallest Pygmies, with height in that region being correlated with Pygmy ancestry versus Bantu, and Biaka pygmies have been shown to be only 18.5% to 30% “pygmy”, if assuming Mbutis are pure and Bantus are the outside group. Though the latter point explains the overall association they have with West Africans, there is still the remote position of the Mbuti. According to Cavalli Sforza, the San and Bushmen don’t necessarily share a particularly close relationship but both their lifestyles and apparent divergence from Bantus makes the idea rather convincing.
Based on the new study, which is though scant on including pygmies, comparing Mbuti dates to San shows similar dates to what was estimated at the high range of the previous 90k-195k split, if not a little higher. This is also consistent with the pygmies (in pure form) being intermediate between West African ancestors and San in the 1994 study and the new date for the Khoi-san. Their more or less genetic isolation may’ve played a role as well in their similar position with other African due to limited geneflow compared to the Khoisan and Biaka being connected through the Bantu Expansion, undermining the affinity Khoisan and Mbuti have through common ancestry. Basically similar to the relationship of Sardinians and mainland Italians which reflects a similar distance relationship with. ]
Now, the first thought crime most are pondering at this point is whether or not the Khoisan are fully human in the context of genetics and recent anthropology? John Hawks already discussed the position of the ancient moroccans in our evolutionary tree and expresses the authors’ comments on how, despite their archaic features restrain them from being clearly modern, they and similar finds play the role as the founding lineage to contribute to modern Sapiens.
In Hublin and colleagues’ “pan-African” hypothesis, every African fossil that had parted ways with Neanderthals is part of a single lineage, a stem population for modern humans. They connect the evolution of these early H. sapiens people to a new form of technology, the Middle Stone Age, which was found in various regions of Africa by 300,000 years ago.
So how many other archaic groups were in Africa? Under the Hublin model, there may have been none. Every fossil sharing some modern human traits may have a place within the “pan-African” evolutionary pattern. These were not river channels flowing into the desert, every channel was part of the mainstream.
But there may be a problem. Geneticists think there were others.
To which he alludes to Iwo Eleru findings, found to be closest to Early AMH (120k levant)
Now, as for cranial representatives that the Ballito Boy likely is associated with, there has been indeed quite a few earlier skulls fitting the profile that were classed separate of more archaic types of similar geography like Florisbad, and thus would be classed away from the Moroccans as well.
An example being this rather interesting analysis of the Border Cave skull (which I believe is 50k, at a site which bushman-like tools dated at 46k).
When all (six rather than just three) discriminants are
considered, Border Cave in fact lies closest to the Hottentot
centroid and is contained within the .05 limits of this distribution.
The fossil also approaches the Venda and Bushman male
centroids but falls beyond the .05 limits of these groups. This
is new information, not principally because of the Hottentot
identification, which is dubious, but because Border Cave is
shown emphatically to be well within the range of modern
African variation for the measurements used. The cranium is
heavily constructed, but it is hardly archaic in the fashion of
Florisbad or Broken Hill.
border cave front view- yooniqimages.com
border cave skull lateral view- yooniqimages.com
Hottentot (Khoi pastorlist) skull, Lateral and Front, (for comparison)
And here’s the best primary reference of a “bushman skull” I could find to display it’s similarities and differences with more admixed Pastoralists. One listed trait that’s notable is the less prominent occipital protrusion of the Bushman skull despite being measured as more dolichocephalic, probably due to a narrower relative breadth but that cannot be seen here.
However the only one I know of that is linked with Khoisan with modern research , is the similar Fish Hoek specimen.
Humanitec-Anatomy of an intellectual triad
Primitive Man of the Peninsula. Cape Times (South Africa), October 26, 1927
One Hundred Skulls: OEC and Exploring Human Origins
In comparison to Jebel Irhoud 1
Zetaboards (Anthroscape), unknown source
front and lateral view Jebel Irhoud- yooniqimages.com
And Florisbad
Ira Block Photography
And comments from the study mentioned, which links Fish Hoek with modern Khoisan, comparing morphological differences among Stone age African Skulls, Bushman, Pygmies, and Bantu Farmers.
To summarize, therefore, the Pleistocene skulls from across Africa tend to be broad,long, with a broad face and broad, short orbits.By contrast, the skulls of the Khoisan (“Bushman”) population are relatively short,low, broad, narrow, with a comparatively intermediate nose.Pygmies are characterized by great variability, but they usually have small-sizedround skulls, and a balanced face. Their degree of dispersion, however, contradicts the findings of other studies, which have detected a strong homogeneity among Pygmy populations, even if these support the hypothesis that the typical features of these populations, including their short stature, took place after their geographical separation through convergent evolution. As is suggested by other more recent studies (Ramírez Rossi y Sardi, 2010; Anagnostou, 2010; Vigilant, 1989).The Bantu-speaking populations are mostly at the center of the graph, which rep-resents a common morphological tendency, but with a strong variability, whether they come from Southern, Eastern or Central Africa. This supports the idea of a common, more recent ancestor than that for the Pygmy and Khoisan groups, as well as a similar way of life founded on cattle breeding and farming, independent of their surrounding environment.The Late Peopling of Africa According to Craniometric Data. A Comparison of Genetic and Linguistic Models
For context, the specimen in the sample that exemplifies the traits associated with the Pleistocene group the most would be the Herto Skull, which is comparatively closer to modern humans than the Jebel Irhoud findings.
160,000-year-old skulls fill crucial gap in evolution- Telegraph
So despite their divergence being closer to the age of more archaic specimens, why do their likely less admixed ancestors and modern populations contrast clearly in phenotypical traits? This would, by my amateur speculation, leave two options. Either gracilization took place in convergence with other populations or a more plausible route that the archaeological finds don’t precisely place the specimen’s actually divergence, thus the more archaic forms likely have older splits than what their fossilized age suggest and the clear traits of “Modern human” phenotype possibly being older as well in that respect.
NotPoliticallyCorrect 
[…] necessarily, as the study noted how their findings conform to recent findings that actual grounds African […]
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Re: the sources (below) that you linked under the other topic:
https://www.biorxiv.org/content/early/2017/01/18/101410
http://anthropogenesis.kinshipstudies.org/blog/2017/01/25/world-science-en-route-from-out-of-africa-to-out-of-america-first-stop-is-out-of-asia/
I am not an expert in genetics, and the paper you linked (which I cursorily read and read parts of in its full form) makes little sense to honestly, but some things I have noticed so far:
I will have to get back to you later. But from quickly scanning them, the claims of the first link seem very unlikely (but I will of course comment again when I can and have read into it more). There is no evidence for a “multiregional origin of human of autosomes/overall ancestry” as they claim with “1.91-1.96 million years for the first split in modern human autosomes” (a split implying erectus as the last common ancestor in many cases). Genetic distances. The idea is contradicted (for instance by all genetic distance measurements of modern human populations), as well as archaeological/paleoanthropological evidence, and very unlikely afaik.
They are basically proposing a very implausible classic multi regionalism—long debunked— (yet with minor admixture that resulted in all uniparental/mtdna and Ydna lineages in the world somehow being of more recent East Asian origin—with modern various human populations predominantly descended, not from a common sapiens ancestor, but from local archaics, but all having only East Asian uniparental markers). There is , as you may know, a tendency among some researchers in China to argue descent from local Asian hominids/multiregionalism over OOA. I strongly suspect this to be, like similar earlier attempts to prove the same, ideologically motivated.
At the beginning they sate:
“). Support for this model comes from the African location of the earliest fossils of modern humans (White et al., 2003) and the Neutral theory interpretation of the greater genetic diversity in Africans (Cann et al., 1987). The difficulties with this model include the discrepancy between autosomal and Y/mtDNA age, the Y haplotype A00 with age >300,000 years (Mendez et al., 2013), AMH fossils of ~100,000 years old in Hunan of China (Liu et al., 2015),”
On the contrary. This is perfectly consistent with an origin of modern humans in Africa mostly or largely from E. African sapiens, but with some mixture in some groups with more divergent homo sapiens (who diverged earlier ca 270-300,000 bc. And the A00 haplotype is extremely rare. And anyway there has of course recently been found to be some autosomal ancestry in certain African groups from very divergent groups of Sapiens (as your article above discusses) . though most uniparental lineages in modern humans (as far as I know), are more in line with the dated origin of most modern autosomal DNA. Fossils of 100 ka sapiens in China, are also not inconsistent with OOA 2 (as you termed it above).
But their claim regarding YDNA R (which they claim is the origin of all modern Y lineages and originally from East Asia) is based on a theory regarding fast vs. slow SNPs (which I know little about, but suspect that their application of the concept, assuming it is a legitimate one, is not well supported). Their proposed philogeny and chronology of Y and mtdna groups almost, in many cases, seems to be the reverse of that held generally by geneticists (they claim that African L mtdna (which is very diverse in Africa with deeply divergent branches; L0, L1, L2, L3) somehow evolved from South Asian M (rather than the reverse, as other geneticists have concluded).
The second link of course is the blog of German Dzeibel a commenter rather infamous around anthropology blogs like Razib’s and Dienekes’ among others for years and rarely taken seriously) for his bizarre belief that homo sapiens originated in the Americas. I would have to agree with the commenter (to the Dzeibel blog post Andrew O’Willeke in this instance, who said of Dzeibels’s treatment of the Chinese study):
“The conclusions of the paper are contrary to a wealth of very solid scholarship by scores of scientists based upon on Y-DNA, mtDNA, autosomal genetics, and archaeological data.
It is unlikely to survive peer review and be accepted for publication.
Chinese scientists supported a multi-regional hypothesis largely for political reasons for many years, and a few seem to be returning to that path despite the fact that this hypothesis is widely discredited. ”
But I will of course be interested to see the results of peer review, and any other opinions of those with much more technical knowledge in the area of genetics than me (and will try to comment again soon when I the get chance to look at it more closely/carefully and do a bit more research).
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Edit: “Their proposed general picture of philogeny and chronology of Y and mtdna groups they propose is almost, in many cases, the philogenic/taxonomic inverse of that found an held by other genetic research.”
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Edit “…(which I cursorily read and read parts of in its full form) makes little sense to me honestly, but some things I have noticed so far:”
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Yeah, I’m quite familiar with GD, I was even reminded of him when I read Fenton.
Despite this, I try to keep my own bias from infecting my opinions and paired with my lack of understanding in the greater technique when mapping out human genomes to determine ancestry, it was really hard to objectively judge this study especially due to the limited research.
One of the things that I believe result in studies like this is the lack of understanding of OOA humans being different from Modern Africans like Yoruba and similar misunderstandings, but I’m only guessing.
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“But their claim regarding YDNA R, a mid-Upper Paleolithic period offshoot of YDNA P, likely both from central Asia (which they claim is the origin of all modern Y lineages and originally from East Asia)”
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The last comment of course was an edit to my YDNA R point (but I should have labeled it as such). And I will likely comment again on the topic (as mentioned), and perhaps also on their very weak, IMO so far, YDNA R argument in particular—which claims it (the lineage) to be from East Asia near China rather than closer to West Central Asia/Eurasia bordering the East of Eastern Europe, which is more likely)
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“One of the things that I believe result in studies like this is the lack of understanding of OOA humans being different from Modern Africans like Yoruba and similar misunderstandings, but I’m only guessing.”
Yes, I think that likely contributes to it.
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To Jm8,
regarding their centering towards East Asia for R, I have some ideas.
A. on PP’s blog, we came across a study that lumps SE Asians with East Asians generally by Name. Given how they typically form a basal position compared to NE Asians and Europeans, that might have something to do with it.
B. As for them placing R towards East Asia, my guess is biased in trying to come off less “Eurocentric” or being subliminally East Asian Centric like how you and others suggested is the case. However, I restrict my own confidence due to reasons stated before.
And again on the difference between basal Africans and OOA humans, in retrospect, seeing how Eurasians have a higher percentage of the latter cluster compared to populations like the Yoruba and how other African Populations have varying degrees of older lineages, you could sort of shape that relation as a Eurasian source assimilating an Archaic population.
BTW, a commenter under the Dienekes link I had used in the Bruce Fenton article explains how that scenario would be realistic regarding sub-saharans when Dienekes suggests it.
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“And again on the difference between basal Africans and OOA humans, in retrospect, seeing how Eurasians have a higher percentage of the latter cluster compared to populations like the Yoruba and how other African Populations have varying degrees of older lineages, you could sort of shape that relation as .”
Yes, I see what you mean (I too could sort of see someone, not informed of all the evidence, getting that idea, that is, the idea of a Eurasian source assimilating an Archaic population—but the evidence we have does not support it—. I would be interested to see how much basal African various subsaharan East African groups (I would guess usually much less of it), who would be closer to the OOA population (or many of whom would be closer to it): like various Nilo-Saharans ones, Hadzas, and maybe also Horner ethnic groups with little or less Eurasian admixture (than most in the horn)such as Omotic speakers (like the Hamar, Ari and Ongota) and perhaps some of the Cushitic tribes of Southernmost Ethiopia (who nonetheless generally have bit more Eurasian admixture than the Omotics).
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“BTW, a commenter under the Dienekes link I had used in the Bruce Fenton article explains how that scenario would be realistic regarding sub-saharans when Dienekes suggests it.”
Which commenter? The commenter (“Andrew”, I think, if I have the right Dienekes link) seems to be arguing the opposite: for an origin in Africa or modern humans (as the reason for greater African genetic diversity) and relatively a deep/early divergence date between some groups of sapiens in Africa (from an early sapiens common ancestor) predating the OOA (as is supported by archaeological and genetic evidence), resulting in most (though not necessarily all) of the current genetic diversity/divergence between Africa groups (like Pygmies and non Pygmies, etc.).
http://dienekes.blogspot.com/2016/02/archaic-introgression-in-pygmies.html
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Edit: “…and a relatively deep/early divergence…”
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Regarding OOA to Basal African amongst Africans, I would say Horners, Nilosaharans, Niger Kongo Speakers, the Hunter-gatherers minus the more ambiguous relationship of Hadza compared to Khoisan populations.
As for the commenter of Dienekes, yeah I meant to say “unrealistic” in my first comment, that he explains why a Eurasian source + African archaic assimilation wouldn;t make sense.
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“Regarding OOA to Basal African amongst Africans, I would say Horners, Nilosaharans, Niger Kongo Speakers, the Hunter-gatherers…”
Makes sense.
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Will update article.
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Any new findings?
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Nothing much aside from Razib commenting on some skepticism on the age, supported by some possible issues in it’s methodology.
Regardless, modern Sub-Saharans being the result of OOA clusters and older African Lineages is likely. I might contact Jm8 on some help regarding Holocene Sub Sahara.
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