January 9, 2017

Extensive ancient Iberian mtDNA analysis

A very interesting thesis on Iberian ancient mitochondrial DNA is available (found via Bell Beaker Blogger):

Christina Roth, Once upon a time in the West : paleogenetic analyses on Mesolithic to Early Bronze Age individuals from the Iberian Peninsula. University of Mainz (thesis), 2016. Freely availableLINK

As all theses, it is very extensive, and I can only make some comments here (space and time are always too limited, you know), hoping to grasp the most interesting aspects of it.

First of all Roth finds that Iberian hunter-gatherers (HGW in the paper) were not quite like Central European ones (HGC), at least not in the mtDNA. Instead, in this aspect the Central European hunter-gatherers were closer to Eastern European ones (HGE), as well as to the Pitted Ware late subneolithic population of Gotland.



Iberia-only mtDNA analysis


This will be a recurrent issue along the analysis she makes. But let's focus on Iberia by the moment. Notice that she does not just use her own data but also from many other sources, including some unpublished materials, this makes a bit difficult to follow all the details, so I feel I can only focus on the statistical analysis she makes and which is the core of the thesis.

Annotated by me, because I found the abbreviations quite hard to follow

The general overview is confirmed, with minor variations, in the cluster analysis (which I also took the liberty of annotating, but take my notes for what they are: mere scribbling on the margin in an attempt to better understand the data, nothing else):



Particular care not to take the arrows of my notes too seriously: they are just conceptual, a very loose sequencing of the available data for a very tentative visualization of it. If it helps you, cool, else ignore please.

In any case, it seems clear cluster 2 is more influenced by hunter-gatherer genetics and that, with the data available in this study, we reach the end of the timeline within it in the following regions: Upper Ebro and Basque Country (data up to Late Neolithic but see my own 2013 compilation for a longer period), Southern Iberia (up to Chalcolithic) Southeast and Northeast, this one after originally being in the "more Neolithic" cluster 1 (in fact the author does argue for Catalonia as main "gate" for Neolithic genetics into Iberia on light of the available data, which does not include another important "gate", the SE one, for lack of data for the early period).

Inversely, cluster 1 is more influenced by "farmer" genetics, first detected in the Northeast (Catalonia and nearby areas of Aragon) but then also affecting the Northern Plateau and the West (Central Portugal). This last is very important because it is here where a key civilizational hub, the oldest known civilization of the Atlantic shores, emerged in the Chalcolithic, playing a key role in the wider Megalithic and Bell Beaker phenomena. I have at times speculated that it might be the origin of "modernity" in Western European genetic pools but on light of this data I have to recant, the origin should be elsewhere, probably in/around what is now France (and therefore it's not likely to be directly related to Bell Beaker, except maybe in the islands, but rather to Michelsberg/SOM, Artenacian and such -- always in wait of more data, just a cautious hypothesis). 

Finally the farmer-leaning cluster reaches the Southern Plateau, near Madrid, what suggests a N→S move of the then-forming Cogotas I herder culture, rather than the opposite. 

What we do see is not inconsistent with modern Iberian genetics anyhow: while Central Europe seem to have seen an increase of "hunter-gatherer" genetics along time, in Iberia the main tendency is the opposite: an increase of "farmer" genetics and further dilution of the aboriginal genetic pool. There is however at least one clear exception in the Northeast and that is also consistent with modern Iberian genetics. Some regions (south, southeast and the totally unknown northwest) have only fragmentary sequences here, so unclear, although the final tendency, up to the Bronze Age, is to cluster 2b (i.e. mixed but rather tending to "hunter-gatherer" genetics).

To finish with the Iberia-only bloc, notice that these are the lineages found among early Iberian farmers by region (in color those haplogroups associated to the arrival of Neolithic per the available data):



Notice how the pool in the Northern region is quite modern-like, not yet exactly as it is locally today but it would pass quite unnoticed in a map of Europe.


Iberia and the rest of Europe


What about the pan-European context (with the usual huge blanks in France, Britain, etc.)? Quite interesting as well:

Annotated by Maju on fig. 23 (click to enlarge)



As mentioned before, the Iberian hunter gatherers (HGW) appear clearly distinct from their Central and Eastern cousins in the mtDNA analysis. And with all this Iberian dataset it becomes apparent that there seem to be two "zones of admixture": one for Iberians and another for Central Europeans, the difference being on which aborigines they mix with. 

Notice that it is not possible to differentiate here between local Central European and intrusive Eastern European admixture, as both aboriginal hunter-gatherer populations appear closely related in all analyses (maybe an artifact of the sampling strategy or maybe actually relevant, can't say). 

It also caught my eye that a German site (Blätterhöhle, Westfalia, famed because farmer and hunter-gatherers living side by side were located there some years ago), clusters intensely with Iberian hunter-gatherers and related populations. I have to research more on this matter (which I had ignored so far) but I suspect it may be very relevant, because we could get an even longer chain of early "modern" mtDNA pools, adding this site to Paternabidea (Navarre) and Gurgy (Burgundy), spanning a long stretch of Western Europe, an area quite neglected by archaeogenetics so far, it must be said.

It is also worth mentioning that UC (which I believe stands for Unetice Culture) pulls the "Central European zone of admixture" in the PCA downwards, with a polarity of its own, a polarity that should probably be considered as specifically Indoeuropean. 

The cluster analysis confirms much of what I just said above, not annotated for a change:



We see very clearly here a larger cluster more influenced by "farmer" genetics and a smaller one that includes all pre-Neolithic aborigines, plus two populations already post-Neolithic but clearly identifiable as at least largely aboriginal (PWC and BLA), plus a subcluster of Neolithic Iberians, from the North (NSE and EVN) and the West (CPE). 

The author notices that: Bernburg (BEC) and Funnel Beaker (FBC) samples (...) show almost no significant differences to any Iberian group, except to the Early Neolithic of Northern Spain (NSE) and Chalcolithic of East Spain (ESC). Hard to interpret but worth noticing, no doubt.

And there is a lot more in the thesis but I can only review so much, so take a look and tell me and the World if I'm missing something of relevance or you feel I'm misinterpreting something or whatever.

16 comments:

  1. From which direction and time frame do you think the majority of H expanded into Central Europe? I suppose you could break these up into three models 1) Iberia-Brotherton 2) SE Europe-Hervella 3) Eastern Baltic (I assume from CWC)

    I assumed that H expanded with Beaker, and maybe it did in the latest phase and subsequent cultures, but the break in the Mesetas and its decided Central European character seem to pour water on that, at least early on.

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    1. I'd think that Western Europe, rather towards the south and the ocean but not wholly clear. A more nuanced question might be at what moment, because it's not impossible at all that this process had various "moments" and not just one, and therefore various cores and not just one.

      What is apparent from the available data is that there seems to be a zone of "early modernity" in mtDNA genetic pools between (roughly) the Basque Country to the South to Westfalia in the North, going through Burgundy and possibly (but not yet demonstrated) much of modern France. This area is roughly the same where I'd expect Western R1b subclades to have expanded from, based on modern data (but mostly hierarchical diversity, not just frequency), which points to an origin of R1b-S116 in Southern France and of R1b-U106 maybe towards the Netherlands.

      "I assumed that H expanded with Beaker, and maybe it did in the latest phase and subsequent cultures, but the break in the Mesetas and its decided Central European character seem to pour water on that, at least early on."

      I fully agree that the Iberian ancient mtDNA data of this thesis is a bucket of cold water on that hypothesis: of the three major BB centers in the peninsula, only the SE one seems to have a visage of "modernity", of high-H pools (and not that high anyhow), so we have to rethink.

      For me in the case of Germany (and North France, Benelux, Switzerland, etc.) a strong candidate is becoming Michelsberg culture, which expanded southwards in the late Neolithic or early Chalcolithic, totally displacing LBK and bringing Funnelbeaker and Megalithism with it. In the case of Britain and Ireland it is possible that it is associated to Bell Beaker (so far more clear in Ireland but too little data to issue a definitive judgment). Further south, in Aquitaine, the Basque Country, etc. it's possible that it was there all the time since at least early Neolithic but maybe it consolidated with Artenacian. In Catalonia, we see quite clearly here that, after an initial Neolithic moment of "low modernity" or hyper-EEF pools, there is some sort of "reaction" or resettlement (where from?) that makes its genetic pool much more modern. So overall it would seem that there were several distinct processes with maybe a common motif: the coalescence of "mestizo" Atlantic Neolithic cultures, which are indeed related to phenomena like Megalithism and later BB (and Funnelbeaker in North-Central Europe), but are otherwise diverse and experience several unique processes and timelines.

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    2. In many ways this field is like an unfolding plot with a succession of surprises and a surprise ending. I think the coming year will continue to re-cage this narrative. Agree it's possible that more native zones lie within the fringes of Europe and is partly reflected in the mtdna. I'll have to see more data though before I become a believer.

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    3. Never become "a believer", always question even your seemingly best established, most solid theory. Belief and science are eternal enemies.

      Said that, can you think of a better explanation? I can't.

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    4. Hey BBman: this most interesting book abstract just arose in another thread (hat tip to Olga):

      https://www.researchgate.net/publication/262962852_When_Beakers_Met_Bell_Beakers_An_analysis_of_dental_remains - 2011

      I think you will want to read it if you haven't yet, very interesting. It's bilingual French/English, you can skip the French part and in the English part maybe focus on the last chapter abstracts. Lots of quasi-genetic dental morphology demographic inferences within Bell Beaker expansion.

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  2. Regarding Iberia: «Some regions (south, southeast and the totally unknown northwest) have only fragmentary sequences here, so unclear, although the final tendency, up to the Bronze Age, is to cluster 2b (i.e. mixed but rather tending to "hunter-gatherer" genetics).»

    I get the idea that in some parts of Iberia, there´s a clear lack of references about the locals genetic make up.
    And the Northwest (and even Central/West) should harbor a somewhat different hunter-gatherer ancestry, than the ones commonly used as reference.

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    1. I was talking about ancient DNA only: many regions are only known for a very specific period and others just totally lack ancient samples, so it becomes very difficult to paint a complete picture. In fact the study has one map in the final or discussion section where Roth attempts to reconstruct, tentatively, what happened and most of the peninsula is just blank. Exceptions? Central Portugal and the North-Northeast of the peninsula around the Ebro and Pyrenees.

      I did not use that reconstruction but preferred to try my own instead, including as much data as possible but still limited.

      Anyhow, with this study, I believe we get a rather good draft for the genetic paleohistory of the Iberian Peninsula, always from the viewpoint of mtDNA. It can and should be improved and polished, the blanks filled, but I wouldn't expect major changes in the understanding unless blatantly contradictory data arises. Of course it'd be ideal if we also had some autosomal and Y-DNA with similar coverage but this is much better than what we had before and does give a sense of the timeline of the major changes, not always happening when one would have expected them, and also of the continuities, which are no less important.

      "the Northwest (and even Central/West) should harbor a somewhat different hunter-gatherer ancestry, than the ones commonly used as reference."

      The Northwest? We have no ancient DNA (barring La Braña) from that area yet. Or do you mean the Northeast? I don't understand. What I do understand is that mtDNA-wise Iberian hunter-gatherers (HGW) were clearly distinct from Central European ones (HGC), something not apparent in the autosomal DNA known to date (just two datapoints: Lochsbour and La Braña).

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  3. It was just because you have proposed before a different pre-historic background for the «Western» part of Iberia. Being Valencia, a possible exception in the East.
    I also question how villagers, from the rural parts of Iberia, have been represented on these studies.

    Thanks for everything!

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    1. I know what you're talking about because you're bringing this discussion from here to there (let's try to pin it here, OK?) and that is a genetic analysis, made not by me but a guest author but which I agree with in essence.

      → http://forwhattheywereweare.blogspot.com.es/2011/04/guest-post-by-argiedude-west-east-y-dna.html

      What, if anything, do you think is wrong with that analysis?

      "I also question how villagers, from the rural parts of Iberia, have been represented on these studies".

      That's a potentially good question but how relevant? Provincial and district capitals almost only attract people from the hinterland, larger cities are more problematic indeed but small cities are pretty much the same as their surroundings. Also geneticists typically ask people questions about their origins and that of their parents, even grandparents sometimes.

      It may be a an issue now and then, I reckon (for example North Burgos province has no clear "capital" of its own and has a very interesting genetic pool, directly linking it partly to local Chalcolithic inhabitants and constituting a specific sub-population with their own characteristics), but for the wider pattern it should not matter and in this case it is a quite clear trend that repeats almost systematically for all Y-DNA haplogroups and also manifests in at least some mtDNA ones, such as U6.

      So these are the known facts, not a reconstruction. The question then arises: how did these patterns form? And it is with this study that I first find a fact-based sketch with possible periodization, earlier I had to just shrug and conjecture, as we had no info between the Early Neolithic and present day for Portugal (and was even worse for most other regions) now there are some informative aDNA facts with some plausible timelines.

      And a most interesting thing that we cannot but underline is how all or most of these changes, after the initial Neolithic arrival via Italy, seem to be quite strictly regional, unrelated to what happens in Central Europe.

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  4. Thanks for your answer.

    «That's a potentially good question but how relevant? Provincial and district capitals almost only attract people from the hinterland, larger cities are more problematic indeed but small cities are pretty much the same as their surroundings.

    Well, that´s maybe a too generalistic assumption. Small cities may have different types of colonization when compared with large cities, but just because it are small, doesn´t mean automatically, that they were all colonized by locals. «Cosmpolitan vs rural», like you mention (for even much smaller places like Sardinia or the Basque country), can imply some relevant differences. I see that for Basque, for example, you make very detailed descriptions for differences between villages or at least, pinpoint many regional differences. For Tuscans, for example, I was told by an Italian, that they got samples from mountain villages.. Why there would be a different procedure with other populations, is beyond me (or maybe I´m failing to see the point, then my bad, sorry for that and please explain me why I´m wrong) but it´s also something that people should have in mind, when make such comparisons, in the future.

    «Also geneticists typically ask people questions about their origins and that of their parents, even grandparents sometimes.»

    Self declared ancestry is not that reliable, but many studies have been conducted using that method, I guess... Some investigations though, seemingly choose a certain geographical area, for sampling, because it is assumed that people live there, better represent the local («real native») populations.

    Also for your theory, you used how many Iberian hunter-gatherer samples, from where and it covers which period?

    Do you think that it won´t differ from other iberian hunter-gatherers that weren´t sampled yet? If so, why?
    I´m asking this, because I have been finding data very scattered and these comparisons seem somewhat «data lacking», though maybe enlightning. I even think, that we only will have a better idea, on the next decade or so (maybe all the Western Mediterranean area, needs hunter-gatherer DNA information).
    Then maybe we can understand a little better where the pieces fit on the puzzle.

    More to come later... And thanks for participating with me on this interesting discussion!

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    1. I see much conjecture but nothing specific in your mistrust of samples. Surely it can always get better but what I do not see is factual evidence that could support your way-too-imprecise skepticism about the representativity of modern samples.

      "Also for your theory, you used how many Iberian hunter-gatherer samples, from where and it covers which period?"

      Not sure which is "my theory" but I've always tried to consider all samples available in any case.

      "Do you think that it won´t differ from other iberian hunter-gatherers that weren´t sampled yet?"

      I don't know, it depends on how you consider the issue. Individually we all differ, notably in haploid DNA (autosomal DNA however tends to form geographical patterns), what we should all be interested is in the genetic pool, not the individuals so much.

      "I have been finding data very scattered and these comparisons seem somewhat «data lacking»"

      Not sure what you mean again. In any case we have to work with the data we have, otherwise get better one (I cannot myself).

      Some people have already been trying to do that and producing results. I can only assure you that I try to consider all them and not cherry-pick the data when analyzing. Now, if Roth did that properly, that would be another story (I haven't got the time to dwell in all the details of her thesis), in any case it'd be quite cool if you would be specific and not as ambiguous as you are in this last comment.

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  5. «http://forwhattheywereweare.blogspot.com.es/2011/04/guest-post-by-argiedude-west-east-y-dna.html What, if anything, do you think is wrong with that analysis?»

    Nothing, it actually suggests the presence of different pre-historic backgrounds in Iberia (not so different from what I expected).

    «Not sure which is "my theory" but I've always tried to consider all samples available in any case.»

    Then which are those «all samples available»?

    «I don't know, it depends on how you consider the issue. Individually we all differ, notably in haploid DNA (autosomal DNA however tends to form geographical patterns), what we should all be interested is in the genetic pool, not the individuals so much.»

    Then do you think that the genetic pool of other iberian hunter-gatherers shouldn´t differ much from those sampled? If so, why?


    «Not sure what you mean again. In any case we have to work with the data we have, otherwise get better one (I cannot myself).

    Some people have already been trying to do that and producing results. I can only assure you that I try to consider all them and not cherry-pick the data when analyzing. Now, if Roth did that properly, that would be another story (I haven't got the time to dwell in all the details of her thesis), in any case it'd be quite cool if you would be specific and not as ambiguous as you are in this last comment.»

    Like I said, the results seem interesting, and you did well (at least, at first glance).
    As time goes on, the idea that I get (personally) is that this subject is very complex (that´s why I said previously that we would need more data from a good part of the Western Mediterranean). Are there any extensive studies on this subject? I think that there are some evidences about the possibility that farm adoption could have happened (at least partly) in some areas, by local hunter-gatherers and in turn, they could have spread this package into other West Mediterranean areas. Also migrations should and seemingly did indeed occurred between different parts, within the West Mediterranean (etc...), even before the Neolithic so this may confuse us a little, on what should be considered native or not. Add to this, the possibility that rural populations may lack representation on these studies and maybe you can a better view of the current picture. I hope that I was less ambiguous this time. Sorry for anything.

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    1. "not so different from what I expected"

      It's a bit different than what we could expect from the generic 1000 GP samples, which make Spanish (generic, from Valencia?) and Portuguese overlap almost totally. It would be interesting to have a decent autosomal study on the Iberian peninsula with some regionalization but nothing has been produced so far except a very mediocre one:

      → http://leherensuge.blogspot.com/2010/05/new-paper-on-spanish-genetics.html

      It has too many blanks (notably the West, the islands and the wider Basque area) but it seems to show that, while Valencians, central-East Castilians and Asturians are similar, Catalans and Andalusians do diverge (Catalans in a continental direction and Andalusians maybe in a generic Mediterranean one). But, as I said, it is a very poor and limited study, it can be done much better and maybe it would show some more clear patterns.

      "Then which are those «all samples available»?"

      → http://www.amaata.com/2013/09/el-origen-de-las-vascas-y-otras.html

      (The data and bibliography is in the link at the end of the article. An English-version of that entry is also available in this blog and a PDF version was uploaded to my account at academia.edu).

      That's what I personally have done. In what regards to Roth's thesis, please read it and dig in her data yourself.

      "Then do you think that the genetic pool of other iberian hunter-gatherers shouldn´t differ much from those sampled?"

      They are pooled from various locations and independent studies. They all show a mix of mtDNA H and U5 primarily, so I would expect to find that same general pattern elsewhere. But, well, surprise me: the more we know the better we can assess.

      One of the issues I'm interested in is mtDNA V (often only sequenced to HV0 level). We know that it only shows up in known European samples with Neolithic but we also know it was unheard of in West Asian known ancient DNA pools, so I suspect it was picked "on the march" somewhere. Where exactly? Italy maybe? Or is it around Catalonia, where it still shows one of its peaks? Or somewhere near France? Or the Balcans maybe?

      This mystery also may apply to other specific lineages like H3. There are a lot of open questions but the generic mtDNA pools of Neolithic settlers (J, T, N1, W, X, K, etc.) is rather well known. We also know with certainty that aboriginal hunter-gatherers carried at least U5, U4 and H (this last seems to have been absent in Central Europe though, but present in both the West and the East anyhow).

      "we would need more data from a good part of the Western Mediterranean"

      Sure but the region I miss the most is actually Western Europe, notably France and surroundings (Belgium, Britain, etc.) It's not just about Mediterranean stuff but almost certainly about something rather "Atlantic", particularly in relation to the changes we observe in and around the Chalcolithic (not so much in Iberia maybe but at least in the rest of Western Europe).

      A key question here is the origin and spread of Y-DNA R1b (Western European variants: S116 and U106). This is like "the holy grail" of this kind of research but so far no luck, Sir Lancelot. R1b-S116, which is by far the most common and widely distributed one, seems very neatly to stem from Southern France based on modern data (considering all basal or hierarchically-sorted diversity), see the following:

      → http://forwhattheywereweare.blogspot.com/2016/01/basque-r1b-df27.html
      → http://forwhattheywereweare.blogspot.com/2015/06/some-improved-knowledge-of-major-r1b.html

      This alone forces us to consider modern-day France as a key demographic and genetic hub in the formation of modern Western European populations somehow (also pointed by early "modernity" of mtDNA pools in the area, as mentioned before). The big question is exactly how and when?

      ...

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    2. ...

      "Are there any extensive studies on this subject?"

      Not sure which is "this subject" in the sentence. If I understand you correctly, there are indeed many studies but probably not conclusive enough, even though a lot advances every year. It's an open and quite young discipline this one of population genetics, so there are still many open questions, even for a relatively well studied area such as Europe (varies a lot from region to region anyhow).

      "I think that there are some evidences about the possibility that farm adoption could have happened (at least partly) in some areas, by local hunter-gatherers"...

      What we seem to find is rather mixed populations and, from some point on, not anymore "pure" ex-hunter-gatherers, except (and even there with some admixture and some uncertainty about their adoption of some Neolithic practices, at the very least they had pottery and semi-feral pigs) in remote peripheral areas such as Gotland (Sweden).

      You can speculate all you want but I'd suggest you get acquainted with the bulk of the studies first, many of which have been discussed in this blog (or you can also find here links to other interesting blogs, etc.)

      "Also migrations should and seemingly did indeed occurred between different parts, within the West Mediterranean (etc...), even before the Neolithic so this may confuse us a little"

      Actually not so much: the SW Europe (Iberia + France roughly), Italian and NW African regions are quite distinctive before the Neolithic. Italy was separated from the West by a massive ice barrier at the Alps and its technology evolved distinctively (Epigravettian, no Solutrean nor Magdalenian influences). NW Africa is also separated from SW (and even more from Italy) by water (it can be crossed but it does act as a barrier most of the time anyhow); the only exception before Neolithic seems to be c. 22 Ka ago, at the LGM, when Solutrean-like influences arrive to form the first UP/mode 4 techno-culture of the area, which is known as Iberomaurusian or Oranian. IMO this is when European genetics (most notable in mtDNA H1, H3, H4, H7 and V) arrived there, a legacy that is still very apparent also in autosomal DNA (although Y-DNA seems to have been largely erased instead by the Epipaleolithic Capsian inflow, which I associate to Afroasiatic expansion from ultimately Sudan, but in need of clarification re. the exact processes of replacement anyhow).

      So there are three basic West Mediterranean regions that used to be quite isolated from each other in the Upper Paleolithic. It's only with the Neolithic when we see a pattern of homogenization that actually comes from further East, from the area of the Aegean Sea and West Asia ultimately. This flow anyhow did not affect NW Africa except in very specific areas (North Morocco), they have their own "Capsian Neolithic" and also the somewhat mysterious "Green Sahara" Neolithic.

      "Add to this, the possibility that rural populations may lack representation on these studies"...

      Actually there have been studies on at least some specific rural populations such as Maragatos or Pasiegos, etc. In some regional studies like the one on Asturias they were very careful in sampling all the region, or check also the one on Basque and neighbors' mtDNA, which is quite comprehensive and somewhat interesting too.

      They are indeed interesting data sets, which add nuance and fine detail, sure, but they don't radically alter the picture. So I say: read more and complain less, at least until you have a better idea of what is known and unknown.

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  6. «It's a bit different than what we could expect from the generic 1000 GP samples, which make Spanish (generic, from Valencia?) and Portuguese overlap almost totally. It would be interesting to have a decent autosomal study on the Iberian peninsula with some regionalization but nothing has been produced so far except a very mediocre one:

    → http://leherensuge.blogspot.com/2010/05/new-paper-on-spanish-genetics.html

    It has too many blanks (notably the West, the islands and the wider Basque area) but it seems to show that, while Valencians, central-East Castilians and Asturians are similar, Catalans and Andalusians do diverge (Catalans in a continental direction and Andalusians maybe in a generic Mediterranean one). But, as I said, it is a very poor and limited study, it can be done much better and maybe it would show some more clear patterns.»

    Yes, I agree, that subject still lacks data.


    "Then do you think that the genetic pool of other iberian hunter-gatherers shouldn´t differ much from those sampled?"

    They are pooled from various locations and independent studies. They all show a mix of mtDNA H and U5 primarily, so I would expect to find that same general pattern elsewhere. But, well, surprise me: the more we know the better we can assess.

    One of the issues I'm interested in is mtDNA V (often only sequenced to HV0 level). We know that it only shows up in known European samples with Neolithic but we also know it was unheard of in West Asian known ancient DNA pools, so I suspect it was picked "on the march" somewhere. Where exactly? Italy maybe? Or is it around Catalonia, where it still shows one of its peaks? Or somewhere near France? Or the Balcans maybe?

    This mystery also may apply to other specific lineages like H3. There are a lot of open questions but the generic mtDNA pools of Neolithic settlers (J, T, N1, W, X, K, etc.) is rather well known. We also know with certainty that aboriginal hunter-gatherers carried at least U5, U4 and H (this last seems to have been absent in Central Europe though, but present in both the West and the East anyhow).»

    I agree, some key aspects are still poorly understood. Hopefully new studies will give us more light on the mtDNA V, H3 and other presently «mysterious» haplogroups or even haplotypes, for example. And what do you think about the presence of the pre-Neolithic variants of U6 and L1b, L3 (and probably L2 too) in Iberia? It would belong to a different type of hunter-gatherer ancestry?


    "we would need more data from a good part of the Western Mediterranean"

    Sure but the region I miss the most is actually Western Europe, notably France and surroundings (Belgium, Britain, etc.) It's not just about Mediterranean stuff but almost certainly about something rather "Atlantic", particularly in relation to the changes we observe in and around the Chalcolithic (not so much in Iberia maybe but at least in the rest of Western Europe).

    A key question here is the origin and spread of Y-DNA R1b (Western European variants: S116 and U106). This is like "the holy grail" of this kind of research but so far no luck, Sir Lancelot. R1b-S116, which is by far the most common and widely distributed one, seems very neatly to stem from Southern France based on modern data (considering all basal or hierarchically-sorted diversity), see the following:

    → http://forwhattheywereweare.blogspot.com/2016/01/basque-r1b-df27.html
    → http://forwhattheywereweare.blogspot.com/2015/06/some-improved-knowledge-of-major-r1b.html

    This alone forces us to consider modern-day France as a key demographic and genetic hub in the formation of modern Western European populations somehow (also pointed by early "modernity" of mtDNA pools in the area, as mentioned before).
    The big question is exactly how and when?»

    I agree, there´s data missing also from France.

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  7. "Are there any extensive studies on this subject?"

    Not sure which is "this subject" in the sentence. If I understand you correctly, there are indeed many studies but probably not conclusive enough, even though a lot advances every year. It's an open and quite young discipline this one of population genetics, so there are still many open questions, even for a relatively well studied area such as Europe (varies a lot from region to region anyhow).»

    I agree.



    "Also migrations should and seemingly did indeed occurred between different parts, within the West Mediterranean (etc...), even before the Neolithic so this may confuse us a little"

    Actually not so much: the SW Europe (Iberia + France roughly), Italian and NW African regions are quite distinctive before the Neolithic. Italy was separated from the West by a massive ice barrier at the Alps and its technology evolved distinctively (Epigravettian, no Solutrean nor Magdalenian influences). NW Africa is also separated from SW (and even more from Italy) by water (it can be crossed but it does act as a barrier most of the time anyhow); the only exception before Neolithic seems to be c. 22 Ka ago, at the LGM, when Solutrean-like influences arrive to form the first UP/mode 4 techno-culture of the area, which is known as Iberomaurusian or Oranian. IMO this is when European genetics (most notable in mtDNA H1, H3, H4, H7 and V) arrived there, a legacy that is still very apparent also in autosomal DNA (although Y-DNA seems to have been largely erased instead by the Epipaleolithic Capsian inflow, which I associate to Afroasiatic expansion from ultimately Sudan, but in need of clarification re. the exact processes of replacement anyhow). »

    I agree with that only exception at around 22 thousand years ago (at least, is what seems to be easily discernible, by now).

    «This flow anyhow did not affect NW Africa except in very specific areas (North Morocco), they have their own "Capsian Neolithic" and also the somewhat mysterious "Green Sahara" Neolithic. »

    Interesting, I have to read more about this Capsian Neolithic (and «Green Sahara» Neolithic, as well).



    «Actually there have been studies on at least some specific rural populations such as Maragatos or Pasiegos, etc. In some regional studies like the one on Asturias they were very careful in sampling all the region, or check also the one on Basque and neighbors' mtDNA, which is quite comprehensive and somewhat interesting too.

    They are indeed interesting data sets, which add nuance and fine detail, sure, but they don't radically alter the picture. So I say: read more and complain less, at least until you have a better idea of what is known and unknown.»

    Yes, some specific rural areas were studied (thanks for naming which, in concrete), though, I already knew that you had regional data from the Basque country (and thanks for it again) and I also have heard about Pasiegos.
    I don´t know yet about other potential interesting rural areas.
    Hopefully new studies will also shed light about the Western Mediterranean (including France), Neolithic and Pre-Neolithic periods!
    Thanks for everything.

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