R1a problem

[Peterski]

The oldest recorded R1b is from Italy though!

Wasn't Villabruna R1b-V88? Which subclade did he belong to?

[Orion Arm]

Wasn't WHG R1b mostly R1b-V88 (which is a subclade which today exists mostly in Africa)?

In Russia & Ukraine you have many EHG samples with R1b. Both R1a and R1b are from EHG.

I have not really taken a side yet. They probably have an answer to your objection, but I did not follow closely. Yet.

Battle Axe, Fatyanovo or Bell Beaker are the results of founder events.

Simply an older population in which both R1b and R1a existed intermingled with each other, then separated into younger populations and some of which were dominated just by R1a or just by R1b due to founder events (they descended from small numbers of founders). Also it is incorrect to operate just with macro-haplogroups like R1a or R1b. We should look at subclades. For example R1a-Z93 in Fatyanovo, R1b-P312 in Bell Beaker (there is no U106 in Bell Beaker so far, if I remember correctly), R1a-Z284 in Battle Axe, etc.

I'm actually not satisfied with this answer for 3 different reasons:

1). You claim too many cultures occupying too vast geographical spaces to all be results of founding effects

2). Even if those ancient cultures as well as modern Eastern Europeans have lopsided R1a-to-R1b ratios due to founder effects, you didn't address why modern Bell Beakers as well as modern Western Europeans have lopsided R1b-to-R1a ratios (the segregation theory rests on an evidence of mutual segregation, not a one-way one)

3). Subclades don't really address the topic, no matter how many R1a clades exist, this haplogroup is vastly outnumbered by R1b among Bell Beakers and modern Western Europeans, just as R1b is vastly outnumbered by R1a among Eastern Corded Ware as well as modern Eastern Europeans

The theory of disparate migrations of R1b and R1a clans is much more tenable

[Peterski]

I'm actually not satisfied with this answer for 3 different reasons:

1). You claim too many cultures occupying too vast geographical spaces to all be results of founding effects

2). Even if those ancient cultures as well as modern Eastern Europeans have lopsided R1a-to-R1b ratios due to founder effects, you didn't address why modern Bell Beakers as well as modern Western Europeans have lopsided R1b-to-R1a ratios (the segregation theory rests on an evidence of mutual segregation, not a one-way one)

3). Subclades don't really address the topic, no matter how many R1a clades exist, this haplogroup is vastly outnumbered by R1b among Bell Beakers and modern Western Europeans, just as R1b is vastly outnumbered by R1a among Eastern Corded Ware as well as modern Eastern Europeans

The theory of disparate migrations of R1b and R1a clans is much more tenable and robust

But Fatyanovo is all R1a-Z93, Battle Axe is all R1a-Z284 and Bell Beaker is entirely R1b-P312.
It is a fact that these cultures are dominated by specific subclades, not by entire haplogroups.

So they must be the results of founder events.

Modern Western Europeans also have lopsided ratios of various R1b subclades to each other.
For example in Ireland 83% of their R1b belongs to R1b-Z290 subclade (also known as L21).

How do you explains this?

[Orion Arm]

But Fatyanovo is all R1a-Z93, Battle Axe is all R1a-Z284 and Bell Beaker is entirely R1b-P312.
It is a fact that these cultures are dominated by specific subclades, not by entire haplogroups.

So they must be the results of founder events.

Modern Western Europeans also have lopsided ratios of various R1b subclades to each other.
For example in Ireland 83% of their R1b belongs to R1b-Z290 subclade (also known as L21).

How do you explains this?

We're talking about massive geographic spaces (Bell Beakers = half of Europe, Battle Axe/Fatyanovo/Sintashta = even bigger area) being completely dominated by R1b and R1a respectively, and they follow clean geographic patterns rather than being a random mosaic. Both the scale as well as a clean geographic pattern make the theory of multiple recurring bottlenecks untenable (freak of nature odds)

As for the diversity of R1b clades in Western Europe, I'd say most of them developed during and after the Bell Beaker culture. R1b-L21 emerged 4500 years ago, that's chiefly within the Bell Beaker culture

[Peterski]

Yes L21 emerged 4500 years ago and probably on the continent.

But how do you explain that only L21 males (and not males from other subclades) went to colonize Britain?

It is clear that British Bell Beaker culture was founded by one clan.

[J. Ketch]

Wasn't Villabruna R1b-V88? Which subclade did he belong to?

R-L754.

[Opie]

My Y-Haplo is R1b-Z2103.

Same