Natural Selection Transformed European mtDNA?

I only recently discovered Eupedia. I am H1b, and therefore faced with just as many questions as the next H man.
I am no geneticist, no archeologist. So all I can offer is the candidness of the non-specialist.

I took a close look at Maciamo's "Frequencies by Period" in prehistoric Europe, I observe that
- Haplogroup H is virtually absent from paleolithic western Europe.
- Absent to very low in mesolithic western Europe.
- Was rare among neolithic Anatolian farmers when they were in the East - before they started moving west.
- Not significant among Yamna people.
- Then during the Neolithic, it suddenly accounts for 24% of Cardium pottery people, and 33.5% of LBK ; adding up to a total of 22.5% of neolithic Europe.
-Bronze Age : 35.5% Srubna. 42.5% German Bell Beaker.

If one admits that the H women were taken west by newcomers, we may also consider that it probably took more than one wave of mixed "marriages" to explain today's levels of H along the Atlantic fringe.

It is apparently accepted that European hunter-gatherers (I2a) sought refuge in southern Europe when the ice descended on them. If it wasn't Spain, nor Anatolia, the one place left is the (north) Balkans. For some reason (wide dispersal of U, eg), I believe HGs were far more mobile than other populations. When the ice receded, they moved north again, fanning out towards Bavaria, Bohemia, Poland, Ukraine.
In Belarus or thereabouts, they came into contact with R1a people who were heading (north-)west. And have remained there to this day - accounting for the current percentiles of some specific H clades in that area.
Some time later, the Eastern farmers moved from Anatolia to the Balkans, where they stayed quite a while. They assimilated the I2 men they didn't kill, and took some of their H women with them on their trip further west.
The same thing must have happened in the north, first with LBK G2a EEF, then a few thousand years later, when R1b started expanding. Corded ware had 21.5% H women. Unetice : 20.5%. And steadily rising as time passed.
This scenario would explain why the very "Russian" H1b gene ended up in my very French genetic make-up.

Natural selection ? Certainly. We can't rule out the hypothesis of an epidemic that selectively wiped out the non-H women of Central Europe. But if natural selection it was, it may well have been natural selection through... (I'm not kidding) sex-appeal !
In other words, my grandmothers were repeatedly picked by newcomers as wives (or sex-slaves!) because they were simply... so cute !

Thanks for sharing your ideas.

I doubt that mtDNA can influence sex-appeal. That has more to do with beauty (good autosomal genes), character (innate and built on experience), happiness, and so on.

Personally I think there are two main reasons that explain why haplogroup H is so common in Europe today.

1) It was present in all prehistoric groups except Mesolithic West and Central Europeans (as far as we know now). H has been found in Mesolithic Sweden, Lithuania, Russia, and was very probably present in Mesolithic Iberia, Italy and Greece too. H was found among Near Eastern Neolithic farmers (H2b, H5, etc.), and more H came with the Indo-European migrations (H1b, H1c, H2a1, H4a1, H6, H8, H11a, H15). Since maternal lineages were not replaced like paternal ones with new waves of invaders, old H subclades remained and were joined by new ones with each migration.

2) Haplogroup H has been linked with more efficient oxygen consumption by the body, increased fitness and endurance, lower risk of septicaemia, etc. Overall H individuals seem more physical resistant, which in harsher historical times would have been a great advantage for survival (especially among the lower classes who had to toil in the fields most of their lives). The increased fitness and endurance may also have helped H mothers withstand better pregnancies and give birth to more children. Just look at famous H women like Empress Maria Theresa (16 children), her daughter Maria Carolina of Austria -also 18 children), or Queen Victoria (8 children despite her husband dying at age 42).
 
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It has probably a lot to do with the Rh factor incompatibility:

Romulus said:
Rhesus negative blood types peak in Europeans and in Basques among Europeans. Given the distribution local to Europe it's fair to assume that Mesolithic Western Europeans were high or perhaps homozygous for the Rhesus negative blood type.

If a Rhesus negative woman conceives a child with a Rhesus positive man then typically she would not be able to have more than 1 child due to RH factor incompatibility. Heterozygotes are RH positive so there would be no Rhesus factor incompatibility for a homozygous RH negative man conceiving children with a homozygous RH positive woman.

If we have a situation in Neolithic Western Europe where incoming (homozygous) RH positive farmer groups are exchanging wives with local RH negative Hunter Gatherer groups, then we would see a significant decrease in fertility for EEF Male / HG Female pairings. Especially in relation to HG Male / EEF Female pairings. As RH positive alleles spread through HG groups this would further reduce fertility among Rhesus negative women in HG groups.

Unfortunately none of the ancient genomes we have so far have been typed for the Rhesus factor snps/gene (I've checked). But given modern distributions, the only way we could have a peak of RH negative blood types in Basques is almost certainly from some Meso or Paleolithic founder effect in a refugium around the Pyrenees.

The effect of this compounded over thousands of years would explain the disappearance of both mtDNA U5b (local HG mtdna) and Y DNA G2a. Natural selection in effect as you suggested.

Modern medicine can deal with serological conflict, but back then?
 
Unfortunately none of the ancient genomes we have so far have been typed for the Rhesus factor snps/gene (I've checked). But given modern distributions, the only way we could have a peak of RH negative blood types in Basques is almost certainly from some Meso or Paleolithic founder effect in a refugium around the Pyrenees.
Unless the group originally migrating into the Basque region brought the rh negative blood factor from somewhere else like the Fertile Crescent region.
 
And small population groups interbred so much the offspring didn't survive and the influx of new mating partners brought a wave of healthy children
 
I think autosomal incompatibilities with mtdna may play a role as well. If we see that H has an advantage it may mean European autosomes are optimized to work well with H mtdna. In East Asia we may see negative correlations with H mtdna. Something to consider.

From an evolutionary perspective we can also expect the rise of dozens of mtdna variants with positive mutations in the past 10,000 years. The problem with old mtdna studies is that they're looking at very old mt haplogroups. I haven't seen any diagrams with weighted mtdna trees like the ones that were published for y dna some years ago. This either means lack of research or that there is nothing worth researching.

Until I see a weighted tree with mtdna bottlenecking multiple times in the past 13,000 years I remain skeptical about mtdna having much influence.
 

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