R1b-M73 and its Origin

[Ebizur]

My own very inexpert, but somewhat informed layman's opinion is that M73 arose from P297 among hunter-gatherers somewhere in Russia. Those R-FTA35755 hunter-gatherers who turned up in Latvia were the product of movement west toward the Baltic, probably down river valleys from Russia's interior along rivers that empty into the Baltic. 

That sounds like a good bet to me since all samples of R-M73 predating the first millennium BCE seem to be from places between Finnmark in the northwest and northern Kazakhstan in the southeast, and the intervening land is nearly all Russian territory (though, of course, not Latvia and Lithuania, where several of the oldest and most basal examples have been discovered).

The Volga river system fills in a v large part i’d tha space between the Baltic and NE  Kazakhstan. Obviously not all of it but a lot of it. It’s likely the reason why M73 is known across that range in hunter gatherers.

If you assume that R-M73 (or at least its R-Y13204 subclade) has developed among hunter-gatherers of the Volga watershed, then where would you place the ancestors of R-M269 (including the direct ancestor of extant R-M269 as well as all his cousins who are more closely related to R-M269 than to R-M73 but whose Y-DNA has gone extinct at some time before the present day)? In a different part of the Volga watershed? In some neighboring river basin?

According to FTDNA, R-M73 and R-M269 should be descended from two brothers who have shared the same father around 14,396 (95% CI 16,418 - 12,622) years before present.

[rmstevens2]

My own very inexpert, but somewhat informed layman's opinion is that M73 arose from P297 among hunter-gatherers somewhere in Russia. Those R-FTA35755 hunter-gatherers who turned up in Latvia were the product of movement west toward the Baltic, probably down river valleys from Russia's interior along rivers that empty into the Baltic. 

That sounds like a good bet to me since all samples of R-M73 predating the first millennium BCE seem to be from places between Finnmark in the northwest and northern Kazakhstan in the southeast, and the intervening land is nearly all Russian territory (though, of course, not Latvia and Lithuania, where several of the oldest and most basal examples have been discovered).

The Volga river system fills in a v large part i’d tha space between the Baltic and NE  Kazakhstan. Obviously not all of it but a lot of it. It’s likely the reason why M73 is known across that range in hunter gatherers.

If you assume that R-M73 (or at least its R-Y13204 subclade) has developed among hunter-gatherers of the Volga watershed, then where would you place the ancestors of R-M269 (including the direct ancestor of extant R-M269 as well as all his cousins who are more closely related to R-M269 than to R-M73 but whose Y-DNA has gone extinct at some time before the present day)? In a different part of the Volga watershed? In some neighboring river basin?

According to FTDNA, R-M73 and R-M269 should be descended from two brothers who have shared the same father around 14,396 (95% CI 16,418 - 12,622) years before present.

That's an interesting question. Evidently R-M73 did not suffer the same extreme bottleneck that R-M269 suffered. There are just 11 SNPs in the M73 block, but there are 97 SNPs in the M269 block. That's why FTDNA shows the MRCA of M269 around 4,350 BC and the MRCA of M73 around 12,000 BC. Both were probably formed roughly the same time, probably not too far from each other, but M269 ran into some severe hardships and did not achieve much success for nearly 8,000 years. 

Here's a screenshot of a comparison of M269 and M73 using FTDNA Discover's "Compare" function.

[alanarchae]

I’m guessing that in the Mesolithic era when P297 hunters likely started in the Volga-Ural around 10000BC that the M73 guys made a good decision (for hunter-fishers) to follow the Volga system west through the forest zone. Which basically sounds like the Butovo culture (with some spreading even further west to mix with other hunters and form Kunda on the Baltic). M269 seems likely to me to have taken another route that later turned out to be a short straw.

It’s likely (though not absolutely certain) M269 also started its European story on the mid/upper volga interface but then took the southerly route towards the Caspian. The Caspian was enormous in the cebturiew running up to 12000BC and presumably for some millennia after was still very expanded though retreating. I wonder if M269 followed the retreating north shore of the Caspian southwards and ended up in a rather less attractive arid zone.

Another possibility could be that M269 didn’t move beyond the urals until a few millennia after M73. I’d link the spread of M73 with the spread of early Mesolithic pressure flaked micro blades which seem to have spread east to west from tbf urals to the Baltic c.12000BC-8000BC with Butovo c.10000BC onwards being a major player. The next obvious atchaeologcal east-west signal is the neolithic hunter pottery. That’s another possible wave that M269 could be linked to.

[alanarchae]

My own very inexpert, but somewhat informed layman's opinion is that M73 arose from P297 among hunter-gatherers somewhere in Russia. Those R-FTA35755 hunter-gatherers who turned up in Latvia were the product of movement west toward the Baltic, probably down river valleys from Russia's interior along rivers that empty into the Baltic. 

That sounds like a good bet to me since all samples of R-M73 predating the first millennium BCE seem to be from places between Finnmark in the northwest and northern Kazakhstan in the southeast, and the intervening land is nearly all Russian territory (though, of course, not Latvia and Lithuania, where several of the oldest and most basal examples have been discovered).

The Volga river system fills in a v large part i’d tha space between the Baltic and NE  Kazakhstan. Obviously not all of it but a lot of it. It’s likely the reason why M73 is known across that range in hunter gatherers.

If you assume that R-M73 (or at least its R-Y13204 subclade) has developed among hunter-gatherers of the Volga watershed, then where would you place the ancestors of R-M269 (including the direct ancestor of extant R-M269 as well as all his cousins who are more closely related to R-M269 than to R-M73 but whose Y-DNA has gone extinct at some time before the present day)? In a different part of the Volga watershed? In some neighboring river basin?

According to FTDNA, R-M73 and R-M269 should be descended from two brothers who have shared the same father around 14,396 (95% CI 16,418 - 12,622) years before present.

That's an interesting question. Evidently R-M73 did not suffer the same extreme bottleneck that R-M269 suffered. There are just 11 SNPs in the M73 block, but there are 97 SNPs in the M269 block. That's why FTDNA shows the MRCA of M269 around 4,350 BC and the MRCA of M73 around 12,000 BC. Both were probably formed roughly the same time, probably not too far from each other, but M269 ran into some severe hardships and did not achieve much success for nearly 8,000 years. 

Here's a screenshot of a comparison of M269 and M73 using FTDNA Discover's "Compare" function.

To many possible variables to consider but i’d say N73 had a more reliable subsistence strategy and:or environment. M269 may have been in a more risky niche or strategy. If I had to guess i’d suggest M73 had control of large rivers in the forest zone of European Russia. My guess is the Butovo culture https://journals.ub.uni-heidelberg.de/in...8713/72674

You can see from the maps in that report how easy it was to connect between Butavo and Kunda on the east Baltic where M73 is kniwn in the mesolithic. You can see from the dating of the cultured and the shared pressure flaked micro blade technologies that M73 almost certainly spread east to west (Butovo being considerably older than Kunda). 

My guess is that M269, instead of speeding west up the  Upper Volga like M73, instead spread DOWN the Volga into it’s more arid middle and even lower sections. Certainly somewhere different from M73 which likely occupied a large chunk of the forest zone between the west Urals and Baltic.