Although "Mesolithic Iberian" would be more correct, the remains were found in what is now Spain, whereas I very much doubt that the probably EHG like folks who united with the Armenian like folk to become the Yamna came from what is now Karelia (i.e., the Russian Republic of Karelia, the Russian Leningrad Oblast and the North and South Karelia regions of Finland). The portion of the pre-Yamna folk who weren't "Armenian-like" would have been from central Russia, IMO, so "Karelia" fails as a geographic term.
Edit: While I was out socializing with friends this evening, not even thinking about this issue, a sudden thought popped into my head - if such smart people are using the term Karelian, is it because Y haplotype N and maybe I was found with Yamna? I doubt it myself, but that's the only way it would make any sense to apply "Karelian" to those people, if they were a mixture of R1a and N1c and maybe some I1. Not likely though, IMO.
I wouldn't be at all surprised if N is a part of the mix. Look at IR1.(The ancient distribution of N might have stretched all the way toward central Russia, as you pointed out. In fact, it might have reached the far northeast later.) I also think that we now know that J2 is part of the mix too. Then, there's that northern European (and northern Italian) younger cluster of G2a to consider as well. (which might be the royal lineage of France) It's actually R1a and R1b that suddenly seem a little iffy to me. What if R1a, in particular, wasn't actually "Indo-European" to begin with, but instead was Indo-Europeanized after the first stage?
There's that WHG jump that still has to be explained, among other things. What if the Cucuteni Trypillian culture, itself an offshoot of Vinca and Cris, absorbed some of the "R" lineages as it expanded east, and some WHG as well, more than was the case for the farmer cultures further west like LBK? This all took place during a warm period when the area would have been very suitable for agriculture. It happened with I1 after all, where a pre-Neolithic lineage was absorbed into the Neolithic culture,and then underwent its big expansion, probably becoming part of TRB.
(I posted the link to this Wiki article on the thread about the Trypillian temple, but I think it has implications for this discussion as well.
http://en.wikipedia.org/wiki/Cucuteni-Trypillian_culture)
Then, as happened enumerable times in eastern Europe, nomads from Asia appeared on the scene. That's what happened with the Huns, let's not forget, whose invasion caused the Germanic tribes to flee west into the Roman Empire, ultimately bringing about its downfall. In this particular case, perhaps there was a period of stasis, when "Kurgan" culture diffused west, in effect Kurganizing these people, but with very little gene flow. The following period would be more in the nature of a conquest, forcing the abandonment of the Cucuteni-Trypillian sites as people fled west and south, taking some metallurgy and other elements of the Kurgan culture with them. I think Greying Wanderer was implying something like this as well. Could this possibly explain the presence R1b in the west, at least, and a sample like BR1 which would be the product of this kind of mixing?
Perhaps R1a was in a slightly different area. It might have been further north, and spread both west along the northern tier, and east and then south and ultimately into Asia.
The inroads from the steppe proper would have continued in the Late Bronze Age, and further.
The other possibility is that R1b and R1a were always part of the mix, perhaps moving from the area of the Caspian onto the steppe (as Jean Manco and even Dienekes, I think, have always maintained), and joined perhaps by some J2, and G2a and meeting N there. Even if that's the case however, if the people of the western steppe, as well as the people of Samara, can be modeled as half "Ancient Karelian like" and half "Armenian like", how did the extra WHG become part of the mix? I suppose in that case either the western steppe had a lot more WHG, of unknown y lineage, or there was an increase of WHG just before the arrival of the Indo-Europeans, and perhaps then mixing with them. The WHG marginalized in the far northwest and far northeast or even scattered in between the farming settlements (why isn't there a map showing the number and size of both farming and HG sites in central Europe in the Middle Neolithic, for example?) may have finally adopted agriculture through the "Indo-European" invasions and then undergone their population expansion. (I believe Dienekes hypothesized that something like this might have happened, if I recall correctly.) I still think it's more likely that there wasn't all that much HG survival in central Europe. If we look at mtDna frequencies, the only WHG mtDna is basically U5 isn't it, and only some subclades of U5 at that? The U4 came from the east later.
Of course, one other possibility is that central Europe, as the result of repeated population crashes, was rather low in population of any kind at the time of the Indo-Eurpean arrivals. I know there was a recent paper about it. Someone should take a look at the specific dates.
Ed. Well, I dawdled on the way to the Italian bread display at my Italian supermarket last night because I suddenly started thinking about J2 migration paths, and some sneaky, aggressive Wall Street type in a Brooks Brothers suit snatched the last Brick Oven loaf right out from under my nose. It's dog eat dog out there.
Seriously, I'm thinking about this way too much,even when I don't mean to do it!
