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Thread: If the R1a and b clade central variance dates were literally true...

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    If the R1a and b clade central variance dates were literally true...

    I think if the current clade dates were considered spot on then it would have implications that have not been fully worked through. I want this conversation on the basis that R1a and b were not in farming areas before 5000BC which I think is pretty clear from the branching or lack of it before then and indeed for some time after. So essentially the scope of this thread based on a steppe or near-steppe model where their expansion only commences at the end of the Neolithic and early copper age of the region. If you dont agree with the model then that is fair enough but this thread is based on a temporary assumption that this is correct.

    So, in terms of R1a and R1b clades we need to consider the ages and on that basis what cultures or waves they could have been involved in.

    To kick off, the first steppe wave into the Lower Danube and adjacent which Anthony associates with Anatolian and sees these peoples as having moved from the Dneiper to the Danube/Balkans and then onto Anatolia later. This is dated to 4200BC initially. Are there any R1a and b clades actually old enough? It seems to me there should be some sort of trail through of a clade of an old enough age in the Balkans and Anatolia although the steppes themselves are probably a lost cause in terms of a modern trail.

    In terms of R1b the only clade that appears to be potentially old enough and with a distribution that might have some slighly displaced correlation would be M269xL23 which is found in the Balkans, in possibly Balkans-derived Armenians and in Anatolians. I am not saying that existing M269 is old but at least in theory it branched early enough.

    L23 is normally dated c. 3500BC somewhat later so either it had to be a later wave or perhaps it could even have occurred in situ among M269 immigrants in the Balkans. Both options have pros and cons.

    Is there an R1a clade old enough to correlate with this early wave? Remember that there can easily be paradox as the ultimate area these lineages may have ended up may have been Anatolia with perhaps traces in the Balkans so there is no problem if it has a non-steppe distribution today given its complex history.
    Last edited by alan; 07-30-2013 at 11:15 AM.

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    In terms of the other direction, what about the Afanasievo-Tocharian link. By that sort of period 3500BC M73 had had 1500 years to grow and could have been a substantial player somewhere. very few of the other R1b or R1a clades had had any sort of time to grew by 3500BC if the suggested variance dates are correct. How long had the relevant R1a clades been in existence around the time the Tocharians headed east? According to the dated R1a tree posted on another thread, the Z94 group did not exist at the point of the Afansievo culture and the Z93 group would have just been one man in 3500BC. So, you could argue M73 is the only R1b or R1a clade on the steppes today old enough to have been involved in Afanasievo.
    Last edited by alan; 07-30-2013 at 04:22 PM.

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    It can also be argued that other than the odd NW European group almost all of the European group split from one guy who on the R1a chart is placed as living about 3300BC. An excellent fit for Yamnaya but leaves very little evidence that R1a was involved in the pre-Yamnaya waves west from 4200-3300BC which are discussed at some length by Anthony.

    Now I have already commented on r1a clades appearing to be somewhat too young to be involved in Afanasievo.

    R1b's major branches M73 around 5000BC and M269 most commonly placed around 4-5000BC are old enough to have taken place in pre-Yamnaya movements such as Suvorovo and others west and Afanasievo east. Even L23 is usually dated to 3500BC, again somewhat older than the common ancestors of the main European and Asian groups. So, perhaps the old theory of an earlier R1b migration out of the steppe west and east followed by R1a Yamnaya groups does have a basis. Is the difference in R1a and R1b partly to do with chronology then. R1b has always had a peculiar pattern in eastern Europe suggestive of it being a patchy substrate and if it was largely an early wave that was subsequenly replaced etc that would not be a surprise at all.

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    Quote Originally Posted by alan View Post
    In terms of the other direction, what about the Afanasievo-Tocharian link. By that sort of period 3500BC M73 had had 1500 years to grow and could have been a substantial player somewhere. very few of the other R1b or R1a clades had had any sort of time to grew by 3500BC if the suggested variance dates are correct. How long had the relevant R1a clades been in existence around the time the Tocharians headed east? According to the dated R1a tree posted on another thread, the Z94 group did not exist at the point of the Afansievo culture and the Z93 group would have just been one man in 3500BC. So, you could argue M73 is the only R1b or R1a clade on the steppes today old enough to have been involved in Afanasievo.
    That is highly speculative based on dates that might not be accurate. It also isn't ridiculous to say that they might have been Z93*, Z283* or anything upstream of that.
    Last edited by newtoboard; 07-30-2013 at 05:51 PM.

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    Quote Originally Posted by newtoboard View Post
    That is highly speculative based on dates that might not be accurate. It also isn't ridiculous to say that they might have been Z93*, Z283* or anything upstream of that.
    Even those two clades would be around 3500BC and would be one man. It is entirely possible that the real dates are out or not at the centre of the confidence interval are out as you say although that in itself is worth bringing up if it does lead to problems correlating with archaeological dating. However, they should be at least relatively right and it does stand that R1b clades like M269, L23 and M73 in the right general longitude do seem older than the R1a clades. That probably is providing us with some nuance about the differences in their stories.

    I would still say that the main R1a clades of eastern and central Europe and Asia do fit the traditional Yamnaya origin rather well as well as somehow also being involved in the genesis of Corded Ware. However, the earliest steppe waves west into the Balkans, which started perhaps 4200BC seem nearly 1000 years too early for the branching root of those clades, which itself is often significantly older than coalecense/intraclade dates. It just seems to me that R1b has a couple of clades that are significantly older in terms of interclade variance than R1a ones. So, although we often discuss origin point and directions of expansions the differences in modern distribution may also owe a significant amount to chronological differences in the first periods of early expansion.

    It is also striking that the R1b does strongly tend to be associated with the earlier branching off the IE tree - I think Tocharian is best put aside for now as there is too much uncertainty about it. I think there are hints in the DNA branching that the chronological differences may be as big a factor as initial location. The step waves are also divided into the early period 4200BC-3500BC and the big Yamnya phase which seems to have largely entered Old Europe after 3000BC according to Heyd's recent paper. So, there could be a sequence in a steppe model that would explain the differences.

    I think the actual clade pattern of the European steppes itself in 4500-3000BC has been close to erased today. However, it is possible to guess that there could have been a sequence that led to the present associations of R1 with various languages. It makes a certain amount of sense to see R1b as associated with the early exit from the steppes and R1a as following this up in the Yamnaya period. This is of course contrary to my Maykop speculations. However I have an open mind on this and it would also make a lot of sense if R1b was associated with the earlier waves from the steppe before 3500BC. The westerly steppe groups close to the farming boundary in the period 4500BC included the Sredny Stog, Skerla type groups. They appear to have also been mixed groups judging by craniology although probably with a tendency to revert back towards the steppe type due to weight of numbers and female marriage pool. Other groups near the farming boundary were apparently similarly mixed including Mikhailovka I who stretched from the Crimea, Dneiper to the Danube mouth along the Black Sea. These groups simply must have been mixed in terms of yDNA and I would suspect they included non-R lines from the farming world like J2.

    It is possible that R1b could have entered the steppe with farmers when they became part of these mixed groups but I suspect R1b already had a place on the western steppes. I say this because M269 only dates from 4000BC or a little earlier and there are simply no traces of its P297* ancestors of the previous 5000 years, not something you would expect in the farming world and certainly not some enormously expanding group like Cuc-Trp. However, it is possible to picture this in the steppe world.

    Regardless, I am not bothered about whether R1b was indigenous to the western steppes hunters or intrusive. Its not really important. The main point is there were clearly mixed groups in the western part of the European steppes c 4500-3500BC, further mixed by Maykop elements towards the end of that period, and they all would have been on-scene when PIE proper evolved and were therefore part of the PIE population.

    So, puttinh on a pure steppes model hat, I would think that R1b may have been within Stredy Stog groups in the Dnieper-Don area and part of the Skerla-Novodanilkova-Suvorovo elite who were already well linked to the farming world to the west from c. 4500BC before they infiltrated from 4200BC and for some time after. If I had to guess I would suggest they were a predominantly R1b-and non-R mixture. In a purely steppe model I would think R1a was contained in the Late Khvalynsk-Repin groups further east who seem most ancestral to Yamnaya and underwent its main expansion from there with that culture. I actually have a funny feeling M73 got early mixed into this group and somewhat separated from M269.
    Last edited by alan; 07-30-2013 at 10:05 PM.

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    Quote Originally Posted by alan View Post
    To kick off, the first steppe wave into the Lower Danube and adjacent which Anthony associates with Anatolian and sees these peoples as having moved from the Dneiper to the Danube/Balkans and then onto Anatolia later. This is dated to 4200BC initially. Are there any R1a and b clades actually old enough?
    I agree with newtoboard that the methods used for dating some relatively old R1a or R1b subclades are not accurate enough to determine with high probability whether a given branch expanded let’s say 4200 or 3600 BC. The margin of error is usually too large in all such cases.

    When regarding your above question, the R1a-Z645 branch seems to be old enough. Even the expansion of each of its two major sub-branches, i.e. Z93 and Z283, could be potentially dated to the 4200-3600 BC period. However, both these clades seem to be strongly associated with some very specific branches of IE (Indo-Iranian and Balto-Slavic, respectively), hence it seems nearly impossible that any of them could have been also specifically associated with the very early separated Anatolian branch. Also, no Z645* cases have been found that could have potentially correspond to the Anatolian branch. Thus, associating R1a with Anatolians seems to be indeed a very risky move.

    Let me also make some comments regarding the suggested association between the Suvorovo-Novodanilovka group and the Pre-Anatolians. There are actually many reasons why I think this connection is rather unlikely:

    1) The linguistic distance between the Anatolian, Tocharian and Late PIE branches is IMO much too large to correspond to the very small time periods between 4000 BC (when the Suvorovo group could have been separated from the remaining Sredny Stog/Khvalynsk group), 3300 BC (or actually any date between 4000 and 3000 BC suggested for the separation of the Tocharian branch) and 3000 BC (when the Corded-Ware-related Balto-Slavic branch is supposed to have been separated from the rest). Actually, the difference between the Anatolian and all remaining IE languages is so huge, that I doubt it can be explained by any strong influence of the local substratum met in Anatolia. IMO, this rather suggests some very early separation of the Anatolian branch, followed by at least 1500 years until the Tocharian-related split took place and at least next 500 years before the Late PIE unity was broken.

    2) After Suvorovo-Novodanilovka has contributed to the Cernavoda culture (4000-3200 BC), its further expansion was mostly directed west towards Central Europe, and much less towards Anatolia. Apart from the appearance of the Ezero culture (3300-2700 BC) that is considered to be a “missing link” between the steppe and Anatolia , this has led to the formation of the Baden (3600-2800 BC), Cotofeni (3500-2500 BC) and Vucedol-Kostolac (3000-2000 BC) cultures, suggesting that all these cultures, forming the so-called Balkan-Danubian complex, were created by people speaking an archaic IE language, related to Anatolian. This practically leaves no room for any subsequent “non-Anatolian” Yamna-derived (or Usatovo-derived?) wave of Late PIE-speaking people directed westward. Also, the Yamna-derived Usatovo culture is dated to 3500-3000 BC, which makes the distance between the separation of the Pre-Anatolian-speaking Suvorovo-Cernavoda population and the westward migration of the Late PIE-speaking West Yamna/Usatovo people incredibly small (500-700 years only!). Of course, it seems nearly impossible to place the Tocharian “departure” in between, the way it would make any sense from the linguistic point of view.

    3) The PIE-derived wheeled-vehicle vocabulary is actually missing in the Anatolian languages, which makes their connection with Sredny Stog and Suvorovo-Novodanilovka somehow less likely.

    4) The only potential Balkan-derived (or steppe-derived) subclade of R1b that could theoretically correspond to the early separated Anatolian branch is the paragroup M269*, and it seems that the age and internal structure of this group is not known well enough to verify the above hypothesis.


    Quote Originally Posted by alan View Post
    So, you could argue M73 is the only R1b or R1a clade on the steppes today old enough to have been involved in Afanasievo.
    I cannot agree with that. I’ve seen the R1a-Z93 branch being dated to about 3500 BC, 3700 BC, and most recently to about 4100 BC (in the Igor Rozhanskii’s latest tree), so I see no reason to exclude this R1a clade from a group of potential contributors to Afanasevo. Also, newtoboard is right that in the case of Afanasevo we cannot exclude finding an extinct sister clade (or some early separated subclade) of Z93.


    Quote Originally Posted by alan View Post
    R1b's major branches M73 around 5000BC and M269 most commonly placed around 4-5000BC are old enough to have taken place in pre-Yamnaya movements such as Suvorovo and others west and Afanasievo east. Even L23 is usually dated to 3500BC, again somewhat older than the common ancestors of the main European and Asian groups.
    There are several issues that need to be resolved before speculating on any specific involvement of M73, M269*, Z2105 and L51 in the hypothetical IE-related movements in Eurasia.

    First, I suspect that the date you provide for M73 is a coalescence age (or TMRCA) for the entire clade, including the potential Western European sub-branch that seems to be very distantly related to the potential Eastern (Eurasian) branch. I would love to compare TMRCAs calculated for the entire M73 clade with those provided for the Western subgroup, Eastern subgroup, and two apparent subgroupings of the Eastern group, respectively.

    Secondly, I guess the above-mentioned age for M269 (4-5000 BC) is supposed to represent TMRCA for the entire M269 clade, while when looking for some possible associations between M269* and the Anatolian branch we need to know the age estimation for M269*, i.e. for M269(xL23). Also, it would be extremely useful to know the geographical distribution and age of some evident STR-based clusters within this group. For example, it is crucial to estimate whether the Balkan (and specifically East Balkan) population of the M269* members indeed represents the oldest group or is rather a recently expanded potential subclade that is much younger than the Anatolian, “East Caspian”, or even Italian group. We simply need to know both the structure and the distribution of the M269* paragroup, before trying to correlate it with any prehistoric IE-related population movements.

    Thirdly, are there any reliable age estimations for the Z2105 clade (or the L23(xL51) group) and for its major subclades L584 and L277?


    Quote Originally Posted by alan View Post
    However, they should be at least relatively right and it does stand that R1b clades like M269, L23 and M73 in the right general longitude do seem older than the R1a clades.
    I think you are exaggerating the difference between the estimated ages for the major subclades of R1a and R1b, respectively. For example, I’ve seen M269 being estimated to be 5.7-7.0 ky old, M73 to be 7.2-8.0 ky old, L23 to be 5.7-7.0 ky old and L51 to be about 4.9 ky old. These TMRCAs are actually at the same level as similar estimations for particular subclades of R1a, including M417 (7.1-7.6 ky), CTS4385 (6.5 ky), Z645 (6.0-6.2 ky), Z93 (5.5-6.1 ky) and Z283 (5.5-5.8 ky).

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    Quote Originally Posted by Michał View Post
    I agree with newtoboard that the methods used for dating some relatively old R1a or R1b subclades are not accurate enough to determine with high probability whether a given branch expanded let’s say 4200 or 3600 BC. The margin of error is usually too large in all such cases.
    This is crucial. I couldn't agree more.

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    Well if nothing else the thread has led to the pointing out of difficulties that would arise in interpretation if the most commonly quoted dates were literally true. I do notice a general feeling feeling that ages may be underestimates cropping up. I must admit I have had a nagging feeling in the same direction for a long time.

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    It looks like STR based age estimates using the currently derived mutations rates produce estimates that are several order of magnitude too young.

    Quote Originally Posted by Wei.et.al.2013

    We have compared phylogenies and time estimates for Y-chromosomal lineages based on resequencing ∼9 Mb of DNA and applying the program GENETREE to similar analyses based on the more standard approach of genotyping 26 Y-SNPs plus 21 Y-STRs and applying the programs NETWORK and BATWING. We find that deep phylogenetic structure is not adequately reconstructed after Y-SNP plus Y-STR genotyping, and that times estimated using observed Y-STR mutation rates are several-fold too recent. In contrast, an evolutionary mutation rate gives times that are more similar to the resequencing data. In principle, systematic comparisons of this kind can in future studies be used to identify the combinations of Y-SNP and Y-STR markers, and time estimation methodologies, that correspond best to resequencing data.
    So not the central variance dates using germline mutation rates cannot be taken at facevalue. I have yet to read the paper, so I won't fully comment on it, but my opinion is that the evolutionary rate produces a rough estimate of the age, but it is far more complicated than that. A far better estimate would be produced if we were to use slow mutating markers and while using a linearization about a given modal value correct for the change in mutation rate as a function of repeat number.

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