posted
I'm beginning to have my doubts about, and believe is just another ancestry that diverged in Africa before modern humans left Africa, thoughts?
Posts: 2595 | From: Vicksburg | Registered: Feb 2006
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quote:Originally posted by the lioness,: You have no quote defining what it is
nothing clearly presented that you think is doubtful
I read literature on it and it seems to be a hypothetical ancestry, not one that has actually been found in any population, essentially a ghost population thats supposed to be non-African, non-West Eurasian and lacks neanderthal ancestry.
Posts: 2595 | From: Vicksburg | Registered: Feb 2006
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quote:Originally posted by the lioness,: You have no quote defining what it is
nothing clearly presented that you think is doubtful
I read literature on it and it seems to be a hypothetical ancestry, not one that has actually been found in any population, essentially a ghost population thats supposed to be non-African, non-West Eurasian and lacks neanderthal ancestry.
Lazaridis made the term popular, you need quotes from him or other geneticists to react to it properly rather than trying to remember what was said and also post that Lazaridis tree chart Dejhuti just posted posted on page 11 of
but since I didn't start this thread my reaction off the top of my head remembering is that proponents of this hypothetical population are not sure if it originated in East Africa or Arabia so that they are not saying it's non-African. They are saying if it's African it is also the base seeding population for Eurasia
but you need some exacts quotes to be accurate
you might want to go to google scholar and type in "Basal Eurasian" and look at various articles describing it. I've done that before looking at how it's used in different articles and when. I never liked the term because it gets mixed into analysis with populations that are not hypothetical as if they are but I suppose it might have value in theoretical modelling
Posts: 42922 | From: , | Registered: Jan 2010
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posted
I noticed wikipedia has an entry called Basal Eurasian with lots of references. I'll read it later
Posts: 42922 | From: , | Registered: Jan 2010
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quote:Originally posted by Elijah The Tishbite: I'm beginning to have my doubts about, and believe is just another ancestry that diverged in Africa before modern humans left Africa, thoughts?
Well nobody knows WHERE exactly Basal Eurasian developed. For all we know it could have developed outside of Africa likely in Southwest Asia (Arabia & Levant). All we know is that it is very similar to Main Eurasian minus Neanderthal ancestry.
Posts: 26246 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
To answer Op's question, No. It doesn't exist.
quote:Originally posted by Elijah The Tishbite:
quote:Originally posted by the lioness,: You have no quote defining what it is
nothing clearly presented that you think is doubtful
I read literature on it and it seems to be a hypothetical ancestry, not one that has actually been found in any population, essentially a ghost population thats supposed to be non-African, non-West Eurasian and lacks neanderthal ancestry.
This is actually correct. BE has been mystified and romanticized. But it all in all was a statistical artifact, representing possibly multiple populations who aren't well modeled by available data. Contrary to popular belief Basal Eurasian is well proxied by SSA populations (See Mbuti and Deep ancestry). But all sampled populations had ancestry the supposed Basal Eurasians did not have, and therefor cant contribute nearly enough ancestry to account for the missing ancestry in studied populations to significance.
This is also why I would caution models of unsampled regions consisting of Basal/Eurasian and ANA. We don't know fully what additional ancestry ANA has, provided by the Epipaleo-Maghreb. We might find that Early Neolithic North East Africans to be 100% ANA and Taforalt/Ifri_ouberrid to be ANA + WHG + Ghost West African.
Posts: 1781 | From: New York | Registered: Jul 2016
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posted
^ That may be the case but the Basal Eurasian found in Old Kingdom Egyptians samples are all derived with the highest amount of BE being found not in Natufian remains but in Neolithic Iranian remains (Hotu Cave). Interestingly, both African Y lineage E-M34 and the Arab-Indian form of HBS is found from eastern Arabia, Mesopotamia, Iran, and as far east as India.
African traits were also found in many of these skeletal remains as Swenet has pointed out in his webpage here: here.
Posts: 26246 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: ^ That may be the case but the Basal Eurasian found in Old Kingdom Egyptians samples are all derived with the highest amount of BE being found not in Natufian remains but in Neolithic Iranian remains (Hotu Cave). Interestingly, both African Y lineage E-M34 and the Arab-Indian form of HBS is found from eastern Arabia, Mesopotamia, Iran, and as far east as India.
African traits were also found in many of these skeletal remains as Swenet has pointed out in his webpage here: here.
I noted those things already, quite a while back I was very open in my assessment that Iranians had more BE than Natufians for example. And that was part of my argument for there not being a single BE population. I disagreed with Swenet on BE. One thing I pointed out was that BE rich populations shown affinity to variable African populations; for example, Natufians show Mota Affinity while ancient Iranians show Affinity to West Africans and Mbuti. He explained that it's because Basal Eurasian had mixed with different groups of Africans before mixing with certain Eurasians and we left it at that..
In retrospect though, while Swenet's explanation isn't completely out of the question, I doubt that the methodology employed by Lazaridis would be powerful enough to single out such a population. He used a complicated assortment of formal stats which included the subtraction of Yoruba-like ancestry and or used proportionality of Neanderthal ancestry and still arrived at a conclusion giving Neolithic and belt cave Iranians more BE than Natufians. There's also Taforalt who has disproportionately higher Neanderthal considering they're at minimum 25% SSA and Takorakori who might be Taforalt with SSA levels of Neanderthal. Also ANA as parsed by Taforalt and Ifri n Amr Mousa (IAM), the early Neolithic Maghreb, can be seen as far as Anatolia in respectable frequencies. The Epipaleolithic Pinarbasi individual is a decent stand in for the Dzudzuana individual who was shown to have contributed the non ANA ancestry to Natufians. They can also show some African ancestry under the right analysis. More and more resolutions will continue to squeeze out the need for "Basal Eurasian ancestry. There's a reason why more and more papers are starting to neglect the BE component as a whole as of late.
Posts: 1781 | From: New York | Registered: Jul 2016
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posted
The problem is the resolution of all these autosomal signals and their disentanglement when used as markers of ancestry. It's difficult tracking autosomal markers than uniparental lineages. Human populations have a history of diverging and converging again.
Tukuler has often asked the question where exactly is the division between African and Eurasian? We see African uniparental lineages both paternal and maternal extending outside of Africa as well as other genetic elements (HBS, HLA) yet people confine Africans to the African continent or worse yet 'true Africans' to Sub-Saharan while North Africa is 'Eurasian'.
^ Note the label of 'Africans' in the left corner should be 'South Africans', this shows you how long the African genomic data with some gaps here and there.
Even many geneticists are beginning to realize that Basal Eurasian is African including folks like Razib Khan so where exactly does BE fit in the above PCA map?? Is it between North African and West Eurasians? Or is it somewhere in the West Eurasian cluster?
Posts: 26246 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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