Where did DF27 originate? and when and how did it expand?

[Webb]

The sticking point with me that I can't get past is that DF17 is pretty clearly not Iberian. It shares Z274 with the north south cluster, so it seems unlikely that Z209 was born in Iberia when DF17 was not when, as of now, they both have Z274 immediately upstream of them. I thought a while ago that maybe a group of Z220 went north east, leaving a group behind who became Z216/Z278, Z214, and M153, but with the discovery that DF17 and Z209 share Z274 in common, that seems impossible now. I guess it's possible that Z196 left Iberians and went north east giving rise to all known subclades below, but all of the Z196 subclades have ties with the nort sea area of Europe including Germany and the Low Countries. I really think France is the missing link. If France was thoroughly tested and we found DF27 as high or higher then what is found in Spain, I think we would possibly have some questions answered.

[razyn]

If France was thoroughly tested and we found DF27 as high or higher then what is found in Spain, I think we would possibly have some questions answered.

There is no requirement that a haplogroup's present area(s) of dense distribution indicate its place of origin; and in fact that is not very often the case. It's more likely to be the case for a young mutation than for an old one. DF27 is pretty old.

[Webb]

There is no requirement that a haplogroup's present area(s) of dense distribution indicate its place of origin; and in fact that is not very often the case. It's more likely to be the case for a young mutation than for an old one. DF27 is pretty old.

You are correct, however, with the current distribution being heavy in the Pyrenees and gradually tapering off as you go west into Spain and equally tapering off as you head east into France, the picture currently places the heaviest distribution in the Pyrenees. As Z196 was most likely born around 1200 to 1000 B.C., you could argue that while DF27 in general is old, Z196 is young and would most likely not be Bell Beaker, and in particular maritime Bell Beaker, as it is smack in the middle of the mountains.

[TigerMW]

You are correct, however, with the current distribution being heavy in the Pyrenees and gradually tapering off as you go west into Spain and equally tapering off as you head east into France, the picture currently places the heaviest distribution in the Pyrenees. As Z196 was most likely born around 1200 to 1000 B.C., you could argue that while DF27 in general is old, Z196 is young and would most likely not be Bell Beaker, and in particular maritime Bell Beaker, as it is smack in the middle of the mountains.

I get that Z196 has a lot of diversity and would be nearly as old as DF27. Why do you think Z196 is much younger than DF27?

[Webb]

I get that Z196 has a lot of diversity and would be nearly as old as DF27. Why do you think Z196 is much younger than DF27?

I got the estimate from the DF27 Phylogenic thread at world families.

[TigerMW]

If groups of maritime bell beakers exited Iberia to the isles, you would think that Z196 would be found equally in all the isles.

Not really. The Atlantic route seems to have led to Ireland more than Britain. So DF27* in SW Ireland today (from the earliest BB arrivals), but Z196 in Britain from Bronze Age movements would fit my prediction nicely. We have evidence of incomers from Iberia and Norway (deduced from isotopes) on the Isle of Thanet, Kent, in the Bronze Age.

I've just updated our haplotype files on P312, including DF27. In the Isles, the DF27 people seem to be more of the English surname types. I'm just not seeing a plethora of Irish and Scottish names. We do have a decent set of Welsh types, but I don't see the pattern in Ireland I was expecting for Maritime associated people. We should ask Paul D (Dub..) look at the surnames. He seems to have very good knowledge on Irish surname origins and history.

[TigerMW]

I got the estimate from the DF27 Phylogenic thread at world families.

I couldn't find estimates in the WFN thread itself but I found a link in that thread to the following. Nordvedt's method yielded a TMRCA for DF27 at 3.7k ybp and for Z196 at 3.5k ybp. The 2nd method is in the same balllpark. I think Z196 is nearly as old as DF27.

I compared mean pairwise mismatches from DF27xL176,2 and its sub-clades with some MRCA calculations. The third column are mean pairwise mismatches calculated with the Arlequin program; the MRCA based on Nordtvedt’s calculator are in the 4th column.

1 df27 20.7 3.7k
2 z196 18.8 3,5k
3 z209 18 2.7k
4 z220 17.6 4.0k
5 z278 17 2.1k
6 m153 15 2.4k

Plotting the numeric SNP order against the mean pwmm produces a polynomial of the third degree; the time interval of the SNP’s as well as the rise in the effective population will cause a deviation of linearity.
Producing a similar plotting with the MRCA’s gives a polynomial function of the 5th degree. Indicating that inherent assumptions in the MRCA calculations are inconsistent.
The pattern changes If one calculates with Nordtvedt method a SNP together with its downstream SNP’s; but still the polynomial is of the 6th degree!
DF27xL176.2 and sub clades 3.9k
Z196 and sub clades 3.5k
Z209 and sub clades 3.2k
Z220 and sub clades 3.2k
Z278 and sub clades 2.4k
Further I like to present the differences of FST values of the subpopulations of the DF27 metapopulation; FST values represent distances in subpopulations and are well used in population genetics:
FST differences from Df27 with:
Z196 0.091
Z209 0.097
L176.2 0.014
SRY2627 0.048
L165 0.141

It looks as if the mean pairwise mismatches and the FST calculations are more reliable to date subpopulations associated with a defining SNP. The Nordtvedt based MRCA calculates the age of an clade including its sub clades acceptable.
When I plot the mean pairwise mismatch of DF27xL176.2 and sub clades (each time including its sub clades) against the associated MRCA I get a straight line with a linear relationship.

The formula is MRCA=1000(0.23xmean pairwise mismatch – 0.65) ybp (R2=0.9718).

The Z220 subpopulation becomes then: 3.4K and not 4.0K. And DF27 subpopulation 4.1K. The L484 subpopulation is aged 1.3K . A small cluster inside a phylogenetic tree including Bob Bjorkman, Nik Okkels and myself have a MRCA of 0.9K.
....

http://www.worldfamilies.net/forum/i...8524#msg138524

[razyn]

I'm glad to see someone besides myself picking up on Spanjool's separate method of TMRCA calculation... but that was a bit over a year ago, and he's actually working on this with new data (and several new DF27 SNPs) more or less as we speak. By coincidence, he just made his first post here yesterday. Not about TMRCA, though -- the topic begins with Geno 2. Anyway I think we can expect some new estimates in the reasonably near future. Whether they differ from the Jost/Nordtvedt estimates remains to be seen; but they are not calculated the same way, and they'll include CTS4065 (and maybe some other SNPs whose ages have not yet been calculated by those methods, such as Z295). I'm looking forward to it.

One significant problem is that any of these techniques need some STR marker values, preferably a lot of them; and stand-alone Geno 2 results (that give us the new SNPs) don't reveal those. Happily, a bunch of the people in our groups with Geno 2 tests had previously done a lot of other testing, including lots of STR markers. Those who only had Geno 2 tests are visible in the SNP results, but invisible in the Classic or Colorized ones.

[Webb]

I couldn't find estimates in the WFN thread itself but I found a link in that thread to the following. Nordvedt's method yielded a TMRCA for DF27 at 3.7k ybp and for Z196 at 3.5k ybp. The 2nd method is in the same balllpark. I think Z196 is nearly as old as DF27.
http://www.worldfamilies.net/forum/i...8524#msg138524

Mike, your 3500 ybp isn't that far off from 1200 B.C. that I pulled from World Families.

[TigerMW]

Mike, your 3500 ybp isn't that far off from 1200 B.C. that I pulled from World Families.

The 3.5k ybp isn't my estimate. That comes from one of Spanjool's runs. It looks like the standard Nordtvedt method has 3.7k for DF27 and 3.5k for Z196. Those are intraclade so I wouldn't be surprised if they were slightly older in reality.

I'm looking at the same thread... at least the one I think you mentioned. I don't see the 1200 BC and I've tried to figure out who calculated it and how. I just looked through "Topic: R1b-DF27 - keeping the phylogenetic tree updated" I can't find it. I guess it doesn't matter, but we are seeing estimates that show Z196 as being close to as old as DF27 and since you mentioned Z196 was "young" I'm trying to see who would give that estimate and how they rate DF27 on the same scale.

This is the relative STR variance all of the 67 STR ht's with DF27+ and then Z196+ confirmed.

DF27 confirmed 1.07 n=656 (includes Z196)
Z196 confirmed 1.06 n=465

Its fair to say that Z196 has swamped or biased the overall results, but the non-Z196 isn't of higher variance.

DF27 confirmed non-Z196 1.06 n=191

This is not conclusive, but I just don't see how the Z196 TMRCA is not close to as old as the DF27 TMRCA. There is a cap on DF27's age. That cap is the age of P312 and DF27 and P312 appear about the same age.

The whole point was I don't think there is much separation between DF27 and Z196. You said "you could argue that while DF27 in general is old, Z196 is young" (post #83) and I'm just saying I don't see that so I was wondering who was estimating that. It doesn't matter, but if someone is finding that Z196 is relatively young I'd like be sure to understand.