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NetNomad
07-13-2018, 08:41 AM
What is Africa? A human perspective
Luca Pagani1,2, Isabelle Crevecoeur3
1 APE Lab, Department of Biology, University of Padova, Italy
2 Estonian Biocentre, Institute of Genomics, University of Tartu, Estonia
3 UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France

Africa is, beyond any doubt, the place where the most complete and continuous hominin fossil record is available, ranging from the earliest phases of differentiation from our common ancestors with the chimpanzees to the finding of the most ancient remains of Homo sapiens (White et al. 2003, Clark et al. 2003, Stringer and Galway-Witham 2017, Hublin et al. 2017) ever found to date. Emergence of Homo sapiens in Africa is roughly placed between 300-200kya (thousand years ago), in accordance with genetic data pointing to an early origin before 260kya (Schlebusch et al. 2017). Additionally, fossil and genetic data agree in placing Africa as the starting point of the major expansion that led our species to colonize the whole of Eurasia, Oceania and the Americas from 70kya (Mallick et al. 2016, Malaspinas et al. 2016, Pagani et al. 2016, Reyes-Centeno et al. 2015).

To fully understand the past evolutionary history of our species, as well as the dynamics that led to the Out of Africa (OoA) expansion, it is important to understand what we mean by “Africa”. From a static, geographic point of view such a definition is trivial and, even considering fluctuations of the shore levels, Gibraltar Straight to the North-West, Sinai isthmus to the North-East and Bab el-Mandeb Straight to the East can be regarded as the long-term gateways out of Africa, the latter two traditionally deemed as favoured exit points for the OoA. This said, however, palaeoclimatic understanding of the potential expansion of ecological niches (Breeze et al. 2016) are important to distinguish what should be seen as crossing of a major barrier, from what was simply a temporary stretching of an African environment across the above mentioned gateways. Palaeoanthropological research has indeed pointed to the Levant (Stringer et al. 1989, Grün et al. 2005, Hershkovitz et al. 2018) and more recently even to Arabia (Groucutt et al. 2018) as places inhabited by humans well before the major 70kya OoA expansion. So should these early remains be considered as failed OoA expansions, or should one simply assume that the African human niche stretched all the way to Levant or to the Arabian peninsula during certain time periods and under certain conditions? And, in contemplating this second hypothesis, how far from Africa should a human remain dating between 200 and 70kya be found to be considered “non-African” both geographically and ecologically?

The permeability of the African boundaries highlighted by the palaeoanthropological research can be invoked, in an opposite sense, when looking at linguistic evidence. Afro-Asiatic languages, one of the four major linguistic groups present in Africa today, are spoken throughout most of North Africa, across the Sahara Desert, along the Sahel and in the Horn of Africa. Given the high diversification and deep splits between these languages, one should assume that such a linguistic family may have originated in Africa. A notable exception, however, is represented by Semitic languages (an Afro-Asiatic sub-family), which are thought to have arisen in the Levant and subsequently expanded in North Africa and in the Horn of Africa within the last 3-4ky (Kitchen et al. 2009). Given the dually “deeply-rooted” presence of Afro-Asiatic languages both in Africa and in the Levant, the linguistic debate on the origin of this family is still open (Kitchen et al. 2009, Ehret et al. 2004) and probably settling on an intermediate “across-the-Sinai” solution. This shows that even relatively well studied cultural packages such as languages point to early interactions between Africa and the neighbouring Eurasian cultures or, in other words, to a geographical shrinking of what can currently be defined as “strictly African” in a long term perspective.

The definition of what is “African” from a genetic point of view is not easier. On one hand, the availability of uniparental markers (chromosome Y and mitochondrial DNA) and of whole genome sequences has enabled us to clearly pinpoint a signature of the OoA expansion. The majority of contemporary humans tracing their ancestry to Eurasian, Oceanian or American populations indeed host uniparental markers belonging to a specific subset of the entire human variability. Such a subset is thought to have originated in Africa and, in its derived form, to have expanded out of Africa while the remaining human uniparental lineages did not (Soares et al. 2012, Karmin et al. 2015). Similarly, the genomes of non-Africans harbour the signature of a bottleneck, or reduction in overall diversity, which can be dated at around 70kya (Malaspinas et al. 2016). As said, this provides an excellent toolset to define whether the ancestors of a given individual took part to the OoA expansion. The scenario, however, is not as clear for contemporary African individuals, which in turn complicates the understanding of the whereabouts of the OoA expansion. Since the OoA, several waves of population back-flow, from Eurasia towards Africa, took place. Genetic data from modern African populations unveiled the presence of major Eurasian genomic components in North (Henn et al. 2012, Pagani et al. 2015), East (Pagani et al. 2012, van Dorp et al. 2015) and South Africa (Pickrell et al. 2014), and dated them to ~800, ~3,000 and ~1,500 years ago, respectively. It has already been shown (Pagani et al. 2012, Pagani et al. 2015, Schlebusch et al. 2017) that proper handling of these “non-African” segments may improve the understanding of the autochthonous African human diversity and, in some cases (Schlebusch et al. 2017), drastically revise our understanding of within Africa human population divergence.

Recent availability of African ancient DNA specimens, however, showed that the Eurasian presence in the continent may not be as recent as understood from modern data. On one hand, ancient samples from East Africa (Gallego Llorente et al. 2015) and South Africa (Skoglund et al. 2017, Schlebusch et al. 2017) pre-dating the inferred arrival of the Eurasian component in the area were, as expected, free from non-African genetic traces. On the other hand, Egyptian mummies from more than 2,000 years ago, hence pre-dating by at least 1000 years the inferred Eurasian migration, could be essentially described as “non-Africans” from a genetic perspective (Schuenemann et al. 2017). Similarly, and perhaps more unexpectedly, post-Neolithic remains from Morocco dating back to around 7kya (Fregel et al. 2018) already showed a predominant Eurasian genetic signature. These recent findings point to i) a long term genetic relationship between North Africa and West Eurasia and ii) potential biases towards more recent dates of current available methods for dating admixture events in modern populations. The relative isolation of North Africa from the rest of the continent, often referred to as “Sub-Saharan Africa” due to the strong separation represented by the Sahara Desert, may imply that the consequences of these recent findings have only a limited impact on our understanding of the broader African demographic history. Such a reassurance may not hold in the light of pre-Neolithic findings, once again from Morocco. Human remains found at Taforalt and dating back to as early as 15kya (van de Loosdrecht et al. 2018) pre-date the Eurasian presence in the area by another 8,000 years and point to the Levantine Natufians (or pre-Natufians) as a plausible genetic source population. Such a deeply rooted, pre-Neolithic interaction between North Africa and West Asia may lead to envisage at least two (entirely speculative) scenarios.

The first one concerns the potential implications for a more, widespread presence of West Eurasian traces in contemporary West and Central Sub-Saharan populations. Currently available data points to the presence of Natufian-like or, in general, West Asian components in Morocco 15kya (van de Loosdrecht et al. 2018) and 7kya (Fregel et al. 2018). The period in between these two dates is known as the “African Humid Period”and was characterized by higher carrying capacity within the broader North African region and, among other features, by the so called “Green Sahara” (D’Atanasio et al. 2018). Such an ecological scenario may have facilitated some level of gene flow of the Natufian-like component attested in Morocco, towards the ancestors of contemporary West and Central Africans, which may have, in turn, spread over most Sub-Saharan populations, hitchhiking on the post-Neolithic expansion of Bantu speaking groups (de Filippo et al. 2012). If this was the case, the wide-spread nature of this component in a gradient-like manner all over Sub-Saharan African populations may make its detection particularly difficult. Overlooking such a presence may reflect in over- or under-estimating splits between Sub-Saharan populations, as already shown by Schlebusch and colleagues (Schlebusch et al. 2017) for the more recent Eurasian components in southern Africans hunter-gatherer populations. Therefore, one may wonder whether the closer genetic relationship between West and Central Africans to Eurasians, compared to South African hunter-gatherer groups, should be seen as a simple South-to-North African differentiation towards East Africans and Eurasians, or whether the above mentioned Natufian-like leaking across the Green Sahara may partly account for such a genetic relationship. Furthermore, abrupt changes in the Natufian-like proportion within neighbouring African populations may create a genetic signature similar to the presence of deeply-rooted genetic components within the population with the smallest Eurasian fraction, similarly to what reported by Skoglund and colleagues (Skoglund et al. 2017). A potential way to rule out this speculation would be to check whether genomic regions that appear as deeply divergent in population A are also particularly attracted by Eurasian-like genomes in population B used as “African reference” in this particular example. Additionally, one may apply local ancestry or chromopainter (Lawson et al. 2012) approaches to mask out genetic regions that are showing a Eurasian-like signature within contemporary African genomes. If these regions are simply reflecting shared ancestry between any African and any Eurasian population, rather than the presence of a Natufian-like genetic leaking across the Green Sahara, then they should be equally present in all African populations and the resulting population split estimates should not be affected by the masking procedure.

The second scenario that stems from the presence of a non-African component in Morocco at least 15kya is a more radical one, and it reflects back on what we may call, genetically, Africa. Putting together genetic evidence for a Northern exit OoA (Pagani et al. 2015) with the archaeological and palaeoclimatic evidence for a drastic reduction of human presence along the lower Nile Valley from MSI4 (60-70kya) until 25kya (Vermeersch et al., 1990; Van Peer, 2004; Vermeersch& Van Neer, 2015), one may postulate that the progressive drying out of the North-East African region from 70kya triggered a population fragmentation in the area. The majority of these fragmented human groups may have, eventually, died out or merged back with the broader Sub-Saharan population. A small subset of them may instead have reached the Mediterranean shores and, subsequently, expanded West, along the North African coast and East, towards Eurasia and eventually admixed with and replaced pre-existing Neanderthal groups in West Asia (Green et al. 2010). This hypothesis is consistent with the fossil record in lower Egypt and upper Nubia during this Late Pleistocene period and until the beginning of the Holocene. Indeed, the oldest and only complete skeleton in this area, the Nazlet Khater 2 individual, dated around 40 Kya, exhibits a combination of plesiomorphic and unique morphometric features that lie outside of extant phenotipyc diversity and could be the consequence of fractioning population in the middle part of the Nile valley at a time of extreme climatic conditions (Crevecoeur, 2008). Such robust phenotype can be detected in subsequent samples in the area dated at around 14-12ky (Wendorf, 1968; Anderson, 1968; Irish, 2005; Crevecoeur, 2008; Antoine et al., 2013) and up to 9kya (Honegger, 2006; Crevecoeur, 2012; Honegger & Williams, 2015), while the fossil record in the northern part of the Nile Valley between 70 and 10.5kya has so far yielded little or no evidence of human presence (Kuper and Kröpelin 2006 Science). Human remains from the Nubian region dating to after 8kya show instead more gracile morphologies (Honegger & Williams, 2015, Crevecoeur 2012), consistent with a reopening of the Nile Valley corridor. The admixture of allegedly African-like middle/lower Nile Valley “more robust” groups with Levantine or North-West African “more gracile” groups after 8kya is compatible with contemporary Egyptians harbouring within their African genetic components (hence the component contributed by the more robust groups) the haplotypes that are most represented outside of Africa today (Pagani et al. 2015). Such a scenario would imply the following: i) a potential cause for the genetic bottleneck that characterizes all non-African group was the progressive increase of aridity of the Nile corridor, rather than the expansion out of Africa of a few wanderers during environmentally permissive conditions; ii) such a bottleneck did not take place at the gateways of Africa but, rather, within Africa (along the Nile basin), and iii) as a consequence of the MIS4 arid period, all subsequent coastal North African populations should be considered “non-Africans” from a genetic viewpoint or, in other words, they should be expected to share the same 70kya genetic bottleneck signature that characterizes all contemporary non-Africans. An interesting implication of this highly speculative scenario would be the presence, in North-Africa, of genetically non-African populations since 60-70kya and, if our understanding of the whereabouts of the human-Neanderthal introgression are correct, then these North African populations should be predominantly free from any archaic genetic signature. Recent ancient DNA studies on West Asian and European populations inferred the presence of a “Basal Eurasian” population (Lazaridis et al. 2014), which is thought to have originated from the same OoA expansion, but to have diverged from other human groups prior to the separation between extant West and East Eurasians and, in all likelihood, even prior to the Neanderthal introgression event (~55kya, Fu et al. 2014). Notably, among modern and ancient populations for which DNA is available to date, Levantine Natufians are among the ones with the highest presence of this so-called “Basal Eurasian” component (Lazaridis et al. 2016). The hypothetical scenario outlined here may therefore point to an identification of Basal Eurasian groups with the populations that inhabited North Africa after the bottleneck event that took place 60-70kya along the Nile Valley and that acted as a Neanderthal-free, non-African reservoir. The separation between Basal Eurasian groups in North Africa and other Eurasians out of Africa may have been facilitated by the reported reduction or absence of human presence along the northern Nile valley between 70kya and 10kya (Vermeersch & Van Neer, 2015, Kuper & Kröpelin, 2006). These two groups may have come again into contact after 25kya, consistently with a potential coastal connection pointed out by the Levantine (Belfer-Cohen and Goring-Morris 2014) and North African (Douka et al. 2014, Jacobs et al., 2017. Barton et al. 2013) material culture. The re-opening of the North Africa – West Asia connection may then have facilitated the entrance of the basal Eurasian component into Eurasia (Lazaridis et al. 2014, Lazaridis et al. 2016) as well as the arrival of Levantine components in North-West Africa. In this light, the Natufian-like component in 15kya Taforalt (van de Loosdrecht et al. 2018) may be seen as an autochthonous North African component enriched by Levantine contacts post 25kya, while the Sub-Saharan signature within the same genomes as the consequence of a relatively recent gene flow from Sub-Saharan human groups. Morphological or genetic analyses on North African human remains dating between 70 and 25kya are needed to conclude whether the Sinai isthmus or the Saharan belt are to be considered as the ultimate gateways of Africa.

NetNomad
07-13-2018, 09:38 AM
TL;DR version: ''Basal Eurasian could be North African, but are they really African? What is African?''

Magnetic
07-13-2018, 11:21 AM
a continent

:biggrin1:

beyoku
07-13-2018, 01:45 PM
Weaksause IMO.

NetNomad
07-13-2018, 07:16 PM
Weaksause IMO.

Elaborate? It seems fairly balanced.

beyoku
07-13-2018, 08:28 PM
Elaborate? It seems fairly balanced.

People born in Africa, have been in Africa for like 100,000 years..... are not really African.
Where else on the planet does this set of circumstances work out?

NetNomad
07-14-2018, 07:07 AM
People born in Africa, have been in Africa for like 100,000 years..... are not really African.
Where else on the planet does this set of circumstances work out?

I think he's trying to tiptoe around that African usually conjures up Sub-Saharan African in most minds.

Perhaps they should just coin a new term like Ancestral North African (ANA / ANCA?).

beyoku
07-14-2018, 01:55 PM
I think he's trying to tiptoe around that African usually conjures up Sub-Saharan African in most minds.

Perhaps they should just coin a new term like Ancestral North African (ANA / ANCA?).

Genetically “Sub Saharan” = Yoruba according to the gatekeepers.
The analysis is sound.
There are so many things wrong with the conclusion, where else on the planet is there a parallel?
Or maybe we should start calling East Asians “Native Americans”.

redifflal
07-14-2018, 02:42 PM
I think he's trying to tiptoe around that African usually conjures up Sub-Saharan African in most minds.

Perhaps they should just coin a new term like Ancestral North African (ANA / ANCA?).

So are they ultimately trying to drive back down to ancestral components that they feel will correlate somewhat to various phenotypes? Isn't it a difficult process just for something relatively small/minor like skin/hair/eye pigmentation (relative to say height or build or facial features)? How much resolution would one need in both aDNA and moderns to get to proper models for phenotypes correlating to various ancestral clusters?

Does the OOA human taking his jolly slow time foraging in southwest Arabia realize he has left Africa? Not sure why geneticists package the OOA as if it is the Mayflower compact lol. Isn't like some group of humans in Africa knew what Africa is, said "no we're done with this place, let's go hump Neanderthals"...Neither is a back-migration also some phenomenal event when you're traveling by foot, not like back-migrating tribe had to wait on shores of Yemen for 10 years in harsh conditions waiting for the bureaucrats at the African Continent Homeland Security Office in Somalia to approve their visa.
Isn't a "back-migration" of a subset of the OOA humans 100,000 years ago likely to be consisting of Negrito-looking phenotypically anyway? How does relation to a proto-Jarawa type group figure in explaining modern phenotype diversities?
https://i.pinimg.com/originals/9d/5b/27/9d5b27daaae3b6248bf9bc0901d7cbfb.jpg

NetNomad
07-14-2018, 04:03 PM
So are they ultimately trying to drive back down to ancestral components that they feel will correlate somewhat to various phenotypes? Isn't it a difficult process just for something relatively small/minor like skin/hair/eye pigmentation (relative to say height or build or facial features)? How much resolution would one need in both aDNA and moderns to get to proper models for phenotypes correlating to various ancestral clusters?

Does the OOA human taking his jolly slow time foraging in southwest Arabia realize he has left Africa? Not sure why geneticists package the OOA as if it is the Mayflower compact lol. Isn't like some group of humans in Africa knew what Africa is, said "no we're done with this place, let's go hump Neanderthals"...Neither is a back-migration also some phenomenal event when you're traveling by foot, not like back-migrating tribe had to wait on shores of Yemen for 10 years in harsh conditions waiting for the bureaucrats at the African Continent Homeland Security Office in Somalia to approve their visa.
Isn't a "back-migration" of a subset of the OOA humans 100,000 years ago likely to be consisting of Negrito-looking phenotypically anyway? How does relation to a proto-Jarawa type group figure in explaining modern phenotype diversities?
https://i.pinimg.com/originals/9d/5b/27/9d5b27daaae3b6248bf9bc0901d7cbfb.jpg

North Africa isn't tropical. Why would a group living there for thousands of years look like tropical island dwellers? Makes no sense. If you are going to use Australoids, the Australians would be a better fit, but they have non-African/Homo Sapien admixture.

redifflal
07-14-2018, 04:26 PM
North Africa isn't tropical. Why would a group living there for thousands of years look like tropical island dwellers? Makes no sense. If you are going to use Australoids, the Australians would be a better fit, but they have non-African/Homo Sapien admixture.

Just trying to understand the significance of both OOA and back to Africa migration in context of near Africa. North Africa is not tropical now, climate has fluctuated in cycles globally several times.

Michalis Moriopoulos
07-15-2018, 03:00 AM
Seems like this preprint is a lot of waxing about an issue that really does not need to be complicated. Context is king. African is a geographical descriptor first and foremost. If you want to apply geographic names to ancestral groups yet still avoid ambiguity, that's fine, just be as specific as possible with whatever name you decide to use. We already do this with modern groups. We distinguish West Asians and East Asians. We distinguish North Africans from Sub-Saharan Africans. We don't use the word "African" by itself in a genetic context unless we're being lazy or if the context is obvious.

Why sweat the names anyway? We're not beholden to them indefinitely. If the term researchers choose for an ancient group becomes inappropriate or unwieldy because of new finds, no problem-- a more precise terminology will make itself available as the need arises. This will happen with UHGs, it will happen with Basal Eurasians, and I'm sure it will happen when we understand how SSAs formed. There was a terminological shift this year already: the Mesolithic component of India was renamed "AASI," with the former term "ASI" being redefined to mean the result of admixture between the Mesolithic South Asian hunter-gatherers and incoming Iranian farmers. Everyone adjusted immediately.

The field is adaptive by necessity. So long as we have an incomplete understanding of the ancient genetic landscape, these stopgap words employed for ancestral groups will remain provisional. Eventually we'll know enough about their formation and relationships with each other to give them more precise names, but for now, generic fluff like "WHG" works just fine; maybe one day we'll be confident enough to call them "Gravettians."

Shamayim
07-15-2018, 06:20 PM
Just trying to understand the significance of both OOA and back to Africa migration in context of near Africa. North Africa is not tropical now, climate has fluctuated in cycles globally several times.
No prehistoric North African skeletons belong to the Australoid type.

Taforalt skeletons were fully "Caucasoid", Afalou skeletons had a slight prognathism but were "Caucasoid" too. Capsian skeletons were Proto-Med. As for Jebel Irhoud skeletons, they were classified as Neanderthal but, aside from their elongated skull and prominent brow ridge, they lacked prognathism and had cold-adapted noses i.e. nothing similar to Australoid.

redifflal
07-15-2018, 09:01 PM
No prehistoric North African skeletons belong to the Australoid type.

Taforalt skeletons were fully "Caucasoid", Afalou skeletons had a slight prognathism but were "Caucasoid" too. Capsian skeletons were Proto-Med. As for Jebel Irhoud skeletons, they were classified as Neanderthal but, aside from their elongated skull and prominent brow ridge, they lacked prognathism and had cold-adapted noses i.e. nothing similar to Australoid.

Are you saying that fully-stabilized Caucasoid-morphology phenotype-bearing populations had come about within African continent in the timeframes of OOA (and back-migrations of the basal Eurasian)? And if so, in which part? North? Horn? I don't particularly have an opinion on this either way. Why would there be cold adapted nose in any part of Africa or nearby Eurasia? Are narrow noses a cold adaptation or a desert environment adaptation? If a fully-stabilized Caucasoid-morphology characterizes the OOA/Basal-Eurasian population, are they able to "revert" to tropical adaptations as in Australoid and Veddoid morphology as they continue into Eurasia? I thought once a trait gets lost it stays lost like how native Americans in Amazon do not have any tropical adaptations...but on the other hand tropical adaptations in everything from facial features to sickle cell carrier gene characterize the entire tropical belt from west Africa to Vietnam. Or maybe native Americans truly lost it due to migration into extreme cold of Siberia, whereas the OOA/Basal never lost it as much and populations in tropical Eurasia were able to "turn on" such features again in favorable climates.

Numidian
07-16-2018, 12:08 AM
As for Jebel Irhoud skeletons, they were classified as Neanderthal but, aside from their elongated skull and prominent brow ridge, they lacked prognathism and had cold-adapted noses i.e. nothing similar to Australoid.

I don't think Jebel Irhoud are "Australoid," but the bolded doesn't sound right. In "The origin and evolution of Homo sapiens" (2016), Chris Stringer says of Jebel Irhoud 1:
"The face is large and especially broad in its upper dimensions, with flat angled cheekbones and a broad but low nose, below which is significant alveolar prognathism."

Shamayim
07-16-2018, 12:35 AM
I don't think Jebel Irhoud are "Australoid," but the bolded doesn't sound right. In "The origin and evolution of Homo sapiens" (2016), Chris Stringer says of Jebel Irhoud 1:
"The face is large and especially broad in its upper dimensions, with flat angled cheekbones and a broad but low nose, below which is significant alveolar prognathism."


Jebel Irhoud's nose was slightly wider than modern-day Caucasoid but he didn't have a broad nose and he clearly lacked prognathism.

24655

Edit: The new picture shows Irhoud alongside an Australoid.

Michalis Moriopoulos
07-16-2018, 01:00 AM
The Ibero-Maurusian skulls were believed to be so similar to Paleolithic/Mesolithic European skulls that they must be of direct relation. Coon wrote a whole chapter about it in Races of Europe. There was no mention of SSA affinities. Now we know they not only did the IMs have SSA, but they were totally unrelated to European HGs. So much for that. People made the same mistake with the "clearly SSA-admixed" Natufians. Grimaldi is likely in the same camp, too.

The 36,000 year old Hofmeyr skull from South Africa was also deemed to have features typical of Upper Paleolithic skulls from Europe. I read a few years ago that Willerslev was attempting to extract DNA from it, but there's been no update. I fear it's probably a lost cause, but it would be illuminating to know.

TuaMan
07-16-2018, 01:44 AM
The 36,000 year old Hofmeyr skull from South Africa was also deemed to have features typical of Upper Paleolithic skulls from Europe. I read a few years ago that Willerslev was attempting to extract DNA from it, but there's been no update. I fear it's probably a lost cause, but it would be illuminating to know.

The Nazlet Khater man from Paleolithic Egypt would be an interesting specimen too. If I recall he was basically a "tweener" himself of archaic and modern morphological traits, but all in all a pretty robust specimen. Unfortunately I'm just not sure how feasible it will ever be to extract DNA from these tens of thousands of year old specimens from these super hot regions in both Africa and Asia, I'm not sure what's worse for aDNA preservation, high heat hyper-arid deserts or super humid tropical environments.

Numidian
07-16-2018, 01:45 AM
Jebel Irhoud's nose was slightly wider than modern-day Caucasoid but he didn't have a broad nose and he clearly lacked prognathism.
Alright, buddy. Again, I don't think the Jebel Irhoud remains are "Australoid." I'm not an anthropologist so I found a source who is one. You're posting an image apparently from the "Exposing Afrocentric lies" Facebook page. My post was about the bolded part of the statement regarding prognathism. Stringer disagrees with you. Don't make a statement that sounds like something is a clear fact when well-respected sources say things are significantly different. That's it. Thanks.

Shamayim
07-16-2018, 11:29 AM
Alright, buddy. Again, I don't think the Jebel Irhoud remains are "Australoid." I'm not an anthropologist so I found a source who is one. You're posting an image apparently from the "Exposing Afrocentric lies" Facebook page. My post was about the bolded part of the statement regarding prognathism. Stringer disagrees with you. Don't make a statement that sounds like something is a clear fact when well-respected sources say things are significantly different. That's it. Thanks.

I don't care what "well-respected sources"(respected by whom btw?) say when anyone can use his eyes and compare Jebel Irhoud with Jebel Sahaba to see that Jebel Irhoud had no prognathism.

Edit: Jebel Irhoud alongside a prognathic skull.

24657

beyoku
07-16-2018, 01:00 PM
I don't care what "well-respected sources"(respected by whom btw?) say when anyone can use his eyes and compare Jebel Irhoud with Jebel Sahaba to see that Jebel Irhoud had no prognathism.

Edit: Jebel Irhoud alongside a prognathic skull.

24657

These physical features in the context of global phenotypic/Genotypic discontinuity are trivial at this point.
Lets assume the premise and conclusion of Pagani is correct.......If my family and I were "Taforalt specimens" would it be accurate to describe our ancestry as a combination of migrants from Sub Saharan Africa and Western Eurasia? I think we all know the answer to that.

We already have the vocabulary to describe whats going on, i dont think we need new vocabulary. This idea has come up before, and while i understand what is being said its language just gives a middle finger to the idea of African Substructure. More importantly it obfuscates the genetic history of population MIGRATION which is the fundamental purpose of many of these studies.......establishing migration history to figure out who was where, when, and who mixed with who.

We need more African centered researchers to study African remains. Eurasians are incorrectly trying to reconstruct Eurasian population history using African skeletons. Eurasians have done an exceptional job reconstructing their history based on the Hundreds of Ancient Eurasian samples.....unfortunately they have reconstructed themselves back into a continent and a time period in which they dont even exist.

redifflal
07-16-2018, 06:08 PM
This fixation on phenotype at such distant times in prehistory is indeed silly. Yes I grant that each person receives their phenotype as a combination from their mother and father, but to try and figure out and prove that phenotypal differences today can be traceable to some kind of internal African substructure or some stabilized phenotype that arose in the OOA is stretching it imho. Folks can be genetically separate and still have overlaps in phenotypes. Example one can compare pseudo overlap in phenotype between modern populations of Indian subcontinent with Mexicans or Dominicans. The main source of genetic distinction between a Dominican and a Bengali is former has West African ancestry while latter has largely a continuous history from the OOA wave. The two are genetically related by the common shared ancestry of the Spanish/mediterranean side of Dominicans with the Iran Neolithic side ubiquitous and also part of the OOA continuity through tropical Asia. Yet in this case the genetically similar part is not the part that gives the phenotype pseudo overlap but rather the genetically distinct parts of AASI vs SSA, both when mixing with a Mediterranid Caucasoid, end up throwing phenotype similarity of sorts.

You would need the circumstances inside Africa to allow for some way of all the proto Caucasoid featuring homo sapiens to somehow pool their features in isolation for any genetic substructure within Africa pre OOA to start correlating with phenotypes stabilized in different parts of the continent. The fact that fossils of R* guy in Siberia from 40kybp exhibits Veddoid features tells me the case for such is not likely. Cheddar man features and I'm not talking of his pigment calls, are also not very Caucasoid but rather in the Caucasoid-Mongoloid-Australoids intermediate range.

Genetic diversity does not have to mean different visible phenotypes. It could very well mean that one genetically isolated population on east side of a forest area in Africa has 12cm long kidneys and the other population on west side of the forest area has 15cm long kidneys lol. We don't even know what genes package in total invariably has an equals equals relation to a particular skin tone, how we can see then that what genes package leads to prognathism or lack of it or to what degree, or nasal width or hook, or skinny or thick lips etc.

TuaMan
07-16-2018, 10:36 PM
We need more African centered researchers to study African remains. Eurasians are incorrectly trying to reconstruct Eurasian population history using African skeletons. Eurasians have done an exceptional job reconstructing their history based on the Hundreds of Ancient Eurasian samples.....unfortunately they have reconstructed themselves back into a continent and a time period in which they dont even exist.

You don't actually know that, though.

beyoku
07-17-2018, 12:54 AM
You don't actually know that, though.

He is basically talking about Eurasians diverging in Africa prior to OOA.
It would be like talking about Native American in China 40 thousand years ago.
Is anyone hypothesizing Native American admixture in the 45 thousand year old East Asian genome? I don’t think so.

TuaMan
07-17-2018, 01:38 AM
He is basically talking about Eurasians diverging in Africa prior to OOA.
It would be like talking about Native American in China 40 thousand years ago.
Is anyone hypothesizing Native American admixture in the 45 thousand year old East Asian genome? I don’t think so.

Of course not, because we know that Native Americans didn't exist yet 45,000 year ago as a distinct cluster. But we don't know exactly how old the primordial Eurasian population is, or where it lived, just yet. Just because there was a Eurasian bottleneck 50,000 years ago, doesn't mean that Eurasians as a whole only came into existence at that time. Before WHG or the Onge emerged out of their bottlenecks, did they not stem from something that was West or East Eurasian immediately prior? So why pretend Eurasians as a whole emerged out of a vacuum.

There was a paper that came out a few months ago inferring Basal Eurasian is upwards of 80,000 years old. Whether you buy that particular age estimate, or even whether or not you believe BE represents a coherent population, that still seems to point to a deeper coalescence in time of the proto-Eurasian population. And that paper didn't even necessarily tell us a whole lot of anything new as far as divergence between SSA and Eurasians goes anyway, since previous studies had already inferred the divergence time between the two to be on the order of 100,000 years.

beyoku
07-17-2018, 02:45 AM
Of course not, because we know that Native Americans didn't exist yet 45,000 year ago as a distinct cluster. But we don't know exactly how old the primordial Eurasian population is, or where it lived, just yet. Just because there was a Eurasian bottleneck 50,000 years ago, doesn't mean that Eurasians as a whole only came into existence at that time.


The main cluster found in Native Americans DID diverge in Asia as a distinct genetic cluster that long ago.


Tianyuan man also possesses genetic similarities to the same South Americans, in a pattern similar to that found for the Papuan and Onge. The new study directly confirms that the multiple ancestries represented in Native Americans were all from populations in mainland Asia. What is intriguing, however, is that the migration to the Americas occurred approximately 20,000 years ago, but the Tianyuan individual is twice that age. Thus, the population diversity represented in the Americas must have persisted in mainland Asia in two or more distinct populations since 40,000 years ago.

If tomorrow we find another 40kya East Asian that is 100% of this component it is erroneous to call it “Native American” if we are talking about East Asian genetic Sub Structure......especially East Asian substructure PRIOR to the time the Americas were even populated.

Secondly If BE is 80kya, this is before geographic Eurasians exists. The bulk of Eurasians ancestry is not some 80kya geographic continuity, No, it’s a much later OOA bottleneck. The language and conclusion of Pagani muddies the waters when researching and addressing African population history and the sources of their varied ancestries. Basically his conclusion is that Africa’s demographic history doesn’t really matter.

Mansamusa
07-17-2018, 08:11 AM
The Ibero-Maurusian skulls were believed to be so similar to Paleolithic/Mesolithic European skulls that they must be of direct relation. Coon wrote a whole chapter about it in Races of Europe. There was no mention of SSA affinities. Now we know they not only did the IMs have SSA, but they were totally unrelated to European HGs. So much for that. People made the same mistake with the "clearly SSA-admixed" Natufians. Grimaldi is likely in the same camp, too.

The 36,000 year old Hofmeyr skull from South Africa was also deemed to have features typical of Upper Paleolithic skulls from Europe. I read a few years ago that Willerslev was attempting to extract DNA from it, but there's been no update. I fear it's probably a lost cause, but it would be illuminating to know.

Really? I imagined the garbled nonsense from Pagani about non-African genetic components in Africans who never set foot out of Africa was basically admitting, albeit grudgingly, that indeed the Natufians were the bi-product of African admixture into Western Eurasians:


Notably, among modern and ancient populations for which DNA is available to date, Levantine Natufians are among the ones with the highest presence of this so-called “Basal Eurasian” component (Lazaridis et al. 2016). The hypothetical scenario outlined here may therefore point to an identification of Basal Eurasian groups with the populations that inhabited North Africa after the bottleneck event that took place 60-70kya along the Nile Valley and that acted as a Neanderthal-free, non-African reservoir.

Natufians had stereotypical SSA features because they were the result of relatively recent migration from Africa. 70 000 years ago North Africa was stereotypical SSA African Savannah landscape with stereotypical looking Africans.

Michalis Moriopoulos
07-17-2018, 08:47 AM
I was just underlining the pitfalls of relying too much on morphology to decide phylogenetic relationships, especially on remains that are very old and predate the crystallization of modern ancestry types. Convergent evolution is a real force. Look how superficially similar the Andamanese are to SSAs despite not being closely related to them. I have no idea what the proto-ENA population looked like, let alone the Out-of-Africa population. I also don't expect Hofmeyr to show any close genetic relationship to West Eurasians despite its cranial characteristics, but I couldn't even begin to predict what its autosomal profile will look like.

Looks to me like Pagani is trying to distinguish ancestral SSA-type African ancestry from African ancestry that is genetically closer to Eurasians. His solution is to call the latter non-African, which I agree with Beyoku is the wrong way to go about it.

Mansamusa
07-17-2018, 12:41 PM
I was just underlining the pitfalls of relying too much on morphology to decide phylogenetic relationships, especially on remains that are very old and predate the crystallization of modern ancestry types. Convergent evolution is a real force. Look how superficially similar the Andamanese are to SSAs despite not being closely related to them. I have no idea what the proto-ENA population looked like, let alone the Out-of-Africa population. I also don't expect Hofmeyr to show any close genetic relationship to West Eurasians despite its cranial characteristics, but I couldn't even begin to predict what its autosomal profile will look like.

Looks to me like Pagani is trying to distinguish ancestral SSA-type African ancestry from African ancestry that is genetically closer to Eurasians. His solution is to call the latter non-African, which I agree with Beyoku is the wrong way to go about it. Point taken. Convergent evolution within the context of populations as far away and apart as Africans and Andamanese makes sense. However, for Eurasian populations in close proximity to Africa, actual admixture should of course be given consideration, especially when other clues such as archaeology and even paternal haplogroups all point to Africa as a source of origin.

TuaMan
07-18-2018, 11:14 PM
The main cluster found in Native Americans DID diverge in Asia as a distinct genetic cluster that long ago.

If tomorrow we find another 40kya East Asian that is 100% of this component it is erroneous to call it “Native American” if we are talking about East Asian genetic Sub Structure......especially East Asian substructure PRIOR to the time the Americas were even populated.

That Native-American like component in Tianyuan, did he or his people have that component when they split from the rest of the East Eurasian family, or did they only acquire it because they mixed at some point with a population that was already pre-Native American? Native Americans sensu stricto came around 15,000-20,000 years, but there must have been something that was pre-Native American that preceded them at some point. Maybe that fusion of ANE+East Asian occurred only a couple hundred years before they crossed over Beringia, or maybe it was thousands of years. You'll say it doesn't matter because their ancestors would just be different subsets of East Asians anyway, but follow your own line of reason further up the family tree.

Tianyuan, Native Ams, Onge, Ami, etc., are all subsets of East Eurasian diversity, and all these subsets ultimately would roll up eventually to an undifferentiated Basal East Eurasian population that they all descend from. The subset populations and the Basal East Eurasian pop itself are more similar to each other than either is to West Eurasians, whom the Basal East Eurasians diverged from at some point. Now simply imagine primordial East and West Eurasians as two structured subsets of a broader generically Eurasian population, or rather stemming from a single node just under Basal Eurasian and later diversifying, and the macro East and West subsets share more with the BE population and vice versa than the BE pop shares with whatever African population it diverged from.

So you could have something that was fundamentally Eurasian that existed, prior to the internal structuring of later Eurasians, just like you could have something fundamentally East Eurasian prior its own structuring.


Secondly If BE is 80kya, this is before geographic Eurasians exists. The bulk of Eurasians ancestry is not some 80kya geographic continuity, No, it’s a much later OOA bottleneck. The language and conclusion of Pagani muddies the waters when researching and addressing African population history and the sources of their varied ancestries. Basically his conclusion is that Africa’s demographic history doesn’t really matter.

Really?

Modern human stone tool assemblages from Jebel Faya, UAE, 125,000 ka (https://en.wikipedia.org/wiki/Jebel_Faya)

Skhul and Qafzeh fossils from Israel, 90,000-120,000 ka (https://en.wikipedia.org/wiki/Skhul_and_Qafzeh_hominins)

Gene flow from modern humans into Altai Neanderthal in Central Asia, 100,000 ka (https://www.eurekalert.org/pub_releases/2016-02/caos-ans022116.php)

Human teeth in China 100,000 ka (https://www.nature.com/news/teeth-from-china-reveal-early-human-trek-out-of-africa-1.18566)

Human finger bone from Arabia, 85,000 ka (https://news.nationalgeographic.com/2018/04/saudi-arabia-finger-human-migration-homo/)

Human cranium from Laos, 63,000 ka (http://www.pnas.org/content/109/36/14375)

Modern human from Manot Cave, 55,000 ka (https://en.wikipedia.org/wiki/Manot_Cave)

So there were modern humans deep in Eurasia from 50,000-120,000 years ago, well before the later "OoA" event. And you can dismiss all the above evidence and say that none of those populations are relevant to the proper OoA expansion, but the point is that modern humans have an obviously long and seemingly pretty consistent record of habitation in Eurasia going back almost 100,000 years ago or more. And the "OoA" pop itself could have easily coalesced for some time in Eurasia before expanding later in all directions. Pagani is just entertaining the idea that some of these groups might have influenced Africa demographically too, which is not as unreasonable as you're making it out to be.

Govan
07-18-2018, 11:56 PM
Anti-modern human African urheimat are funny , they look like they're in the quest of their life.

TuaMan
07-19-2018, 12:41 AM
I'm not "anti-modern human" in Africa, though. I don't exclude Africa from the picture at all. I just think the story is more complicated and involves a broader region and time period than is usually assumed. I am sorry if that prospect offends you.

Mansamusa
07-19-2018, 01:50 AM
........
Really?

Modern human stone tool assemblages from Jebel Faya, UAE, 125,000 ka (https://en.wikipedia.org/wiki/Jebel_Faya)

Skhul and Qafzeh fossils from Israel, 90,000-120,000 ka (https://en.wikipedia.org/wiki/Skhul_and_Qafzeh_hominins)

Gene flow from modern humans into Altai Neanderthal in Central Asia, 100,000 ka (https://www.eurekalert.org/pub_releases/2016-02/caos-ans022116.php)

Human teeth in China 100,000 ka (https://www.nature.com/news/teeth-from-china-reveal-early-human-trek-out-of-africa-1.18566)

Human finger bone from Arabia, 85,000 ka (https://news.nationalgeographic.com/2018/04/saudi-arabia-finger-human-migration-homo/)

Human cranium from Laos, 63,000 ka (http://www.pnas.org/content/109/36/14375)

Modern human from Manot Cave, 55,000 ka (https://en.wikipedia.org/wiki/Manot_Cave)

So there were modern humans deep in Eurasia from 50,000-120,000 years ago, well before the later "OoA" event. And you can dismiss all the above evidence and say that none of those populations are relevant to the proper OoA expansion, but the point is that modern humans have an obviously long and seemingly pretty consistent record of habitation in Eurasia going back almost 100,000 years ago or more. And the "OoA" pop itself could have easily coalesced for some time in Eurasia before expanding later in all directions. Pagani is just entertaining the idea that some of these groups might have influenced Africa demographically too, which is not as unreasonable as you're making it out to be.
What on earth do these dead-end pre-OOA human populations have to do with anything?

beyoku
07-19-2018, 02:19 PM
That Native-American like component in Tianyuan, did he or his people have that component when they split from the rest of the East Eurasian family, or did they only acquire it because they mixed at some point with a population that was already pre-Native American? Native Americans sensu stricto came around 15,000-20,000 years, but there must have been something that was pre-Native American that preceded them at some point. Maybe that fusion of ANE+East Asian occurred only a couple hundred years before they crossed over Beringia, or maybe it was thousands of years. You'll say it doesn't matter because their ancestors would just be different subsets of East Asians anyway, but follow your own line of reason further up the family tree.

Tianyuan, Native Ams, Onge, Ami, etc., are all subsets of East Eurasian diversity, and all these subsets ultimately would roll up eventually to an undifferentiated Basal East Eurasian population that they all descend from. The subset populations and the Basal East Eurasian pop itself are more similar to each other than either is to West Eurasians, whom the Basal East Eurasians diverged from at some point. Now simply imagine primordial East and West Eurasians as two structured subsets of a broader generically Eurasian population, or rather stemming from a single node just under Basal Eurasian and later diversifying, and the macro East and West subsets share more with the BE population and vice versa than the BE pop shares with whatever African population it diverged from.

So you could have something that was fundamentally Eurasian that existed, prior to the internal structuring of later Eurasians, just like you could have something fundamentally East Eurasian prior its own structuring.



Really?

Modern human stone tool assemblages from Jebel Faya, UAE, 125,000 ka (https://en.wikipedia.org/wiki/Jebel_Faya)

Skhul and Qafzeh fossils from Israel, 90,000-120,000 ka (https://en.wikipedia.org/wiki/Skhul_and_Qafzeh_hominins)

Gene flow from modern humans into Altai Neanderthal in Central Asia, 100,000 ka (https://www.eurekalert.org/pub_releases/2016-02/caos-ans022116.php)

Human teeth in China 100,000 ka (https://www.nature.com/news/teeth-from-china-reveal-early-human-trek-out-of-africa-1.18566)

Human finger bone from Arabia, 85,000 ka (https://news.nationalgeographic.com/2018/04/saudi-arabia-finger-human-migration-homo/)

Human cranium from Laos, 63,000 ka (http://www.pnas.org/content/109/36/14375)

Modern human from Manot Cave, 55,000 ka (https://en.wikipedia.org/wiki/Manot_Cave)

So there were modern humans deep in Eurasia from 50,000-120,000 years ago, well before the later "OoA" event. And you can dismiss all the above evidence and say that none of those populations are relevant to the proper OoA expansion, but the point is that modern humans have an obviously long and seemingly pretty consistent record of habitation in Eurasia going back almost 100,000 years ago or more. And the "OoA" pop itself could have easily coalesced for some time in Eurasia before expanding later in all directions. Pagani is just entertaining the idea that some of these groups might have influenced Africa demographically too, which is not as unreasonable as you're making it out to be.

Let me repeat for emphasis
"The bulk of Eurasians ancestry is not some 80kya geographic continuity, No, it’s a much later OOA bottleneck."
I will update that comment to say "125kya geographic continuity". What do any of these remains have to do with Eurasian's M89 derived, mtdna M/N derived, crown Eurasian Derived recently bottlenecked ancestry? Very Very little unless you are native to the south pacific.

If you follow my line of reasoning up the family tree we come to basic conclusion that genetic homo sapien sapien is simply an African species. Again i will say i think his analysis of genetic substructure is sound. It take issue with the idea that its not AFRICAN substructure.

If I am an individual from Sudan, studying Sudanese genetics I want to have the ability to differentiate parts of ancestry that have been in my region for 80 thousand years vs that which came 3000-5000 years ago. I want to differentiate and formulate a narrative of these ancient population migrations using archaeology and anthropology.....just like Europeans do with their Bell Beaker and Indo-European pastoral ancestors. Improper language and incorrect geographic designation of human lineages will have me writing my Wavy Line pottery creating Mesolithic Khartoum ancestors migrated from Arabia......Nah.

redifflal
07-19-2018, 04:00 PM
Let me repeat for emphasis
"The bulk of Eurasians ancestry is not some 80kya geographic continuity, No, it’s a much later OOA bottleneck."
I will update that comment to say "125kya geographic continuity". What do any of these remains have to do with Eurasian's M89 derived, mtdna M/N derived, crown Eurasian Derived recently bottlenecked ancestry? Very Very little unless you are native to the south pacific.

If you follow my line of reasoning up the family tree we come to basic conclusion that genetic homo sapien sapien is simply an African species. Again i will say i think his analysis of genetic substructure is sound. It take issue with the idea that its not AFRICAN substructure.

If I am an individual from Sudan, studying Sudanese genetics I want to have the ability to differentiate parts of ancestry that have been in my region for 80 thousand years vs that which came 3000-5000 years ago. I want to differentiate and formulate a narrative of these ancient population migrations using archaeology and anthropology.....just like Europeans do with their Bell Beaker and Indo-European pastoral ancestors. Improper language and incorrect geographic designation of human lineages will have me writing my Wavy Line pottery creating Mesolithic Khartoum ancestors migrated from Arabia......Nah.

We are having a similar problem with Euro or West Eurasia centric approach to understanding demographic history of South Asia. IMHO if the weather in Arabia and Persia would have been tropical instead of desert the entire genetic diversity of the OOA group would be preserved best in modern populations in the area. But in absence of such, I proposed that lower caste Hindus of northwestern part of the Indian subcontinent have the best continuity from the OOA simply due to high population density. Just understanding the differences between the lower caste Hindus in northwest India versus the lower caste Hindus in eastern India might be sufficient in really understanding OOA, Eurasian diversity, what was already African substructure

Mansamusa
07-21-2018, 07:00 AM
We are having a similar problem with Euro or West Eurasia centric approach to understanding demographic history of South Asia. IMHO if the weather in Arabia and Persia would have been tropical instead of desert the entire genetic diversity of the OOA group would be preserved best in modern populations in the area. But in absence of such, I proposed that lower caste Hindus of northwestern part of the Indian subcontinent have the best continuity from the OOA simply due to high population density. Just understanding the differences between the lower caste Hindus in northwest India versus the lower caste Hindus in eastern India might be sufficient in really understanding OOA, Eurasian diversity, what was already African substructure Sounds very logical, but I think Western researchers are a little too self-centered and self-involved to step back and take this more objective approach. They will always go for approaches where they (Eurasians) are at the center of everything.

Dmitry
07-25-2018, 12:23 AM
Africa is definitely one of the most understudied continents in human genetic variation, despite carrying massive amounts of human genetic diversity. Besides the work of Sarah Tishkoff, not much has been given to Africans.

mainer
09-24-2018, 08:57 AM
excellent read!

MTU
09-26-2018, 09:11 AM
The Human body is a Bio Chemical Machine, The tone of the skin depends on the saturation or the lack of certain elements in our Chemical composition.

Black People have a higher concentration of Carbon ( The essence of energy and life ) The presence of the Sulphur Elements changes the skin tone . The more saturated the sulphur the pale the skin color the the straight the straight / Bright is the hair.

The question is why did mother nature see it fit to chemically change humans ( dilute Carbon concentration ) as she moved down the Evolution lane?

Facts is the further one moves from Blackness the quicker the aging process , The higher the level of carbon in steel the higher is its quality , meaning The intelligent Power behind nature of creation made every Human to be adoptable to prevailing condition

Blackness is the color of Charcoal (KAA) ENDURANCE KUKAA no matter how tough the condition it doesn't look rusty . Rustyness ( KUCHAKAA)

Looking at the Jarawa it hard to tell how old they are...their youthfulness lies deep in their genome but the quality of human deteriorates as humans move downstream further away from the source.


Blackness is this nature of Endurance that made the survival of Humans as a species Possible then now and the future ....

KU KAA ( To last - To Endure )



KAA MAKAA ( like charcoal or Carbon )


KAA (K) In carbon , Carbohydrates ,

ENERGY = KAWI

KAWIA ( Lengthiness of time )

KAWA ( began to exist ) The nature of Primodial Enegery ( Kawi)


The letter K in bantu languages represents the Abstract a pictogram of a Walking Man with one foot forward and a raised arm ( Aktion) that is we get the
KU ( To- initiation of motion ) and KI (Class noun for all immobile objects / lifeless / Abstracts) sounds .