There is some big data that is accumulating about the Upper Paleolithic period in Caucasus and Europe. We have 26000 year old samples from West Georgia and now very important samples from Crimea. (~36000 year old).
This samples from Crimea can be labeled as Proto Gravettian culture. The Gravettian culture is very important for Europe because their autosomes are at the origin of later WHG that appears after the LGM. Gravettian culture is also important because it's the first apparition of the haplogroup I in Europe which later will expand in the form of I2. We had a thread about this subject in the group.
With this new data it's becoming clear that the population that created the Gravettian culture moved via Caucasus to Eastern Europe and from there to Balkans and Western Europe. Replacing the local more archaic humans, who left virtually no ancestry in modern Europeans.
This make sense from the Y DNA point of view because I and J have common ancestors and the oldest cases of J are found in Southern Caucasus.
Based on the Yfull the I and J separated from each other 42000 years ago. Which is consistent with the archaeological dates we have.
And finally the Upper Paleolithic samples from Western Georgia are very unusual. They are quite different from post-LGM period Caucasian hunter-gathers (CHG). Those Caucasian Upper Paleolithic samples have lot shared alleles with Anatolian hunter gatherers and farmers. But even more surprising they had shared alleles with WHG that didn't existed yet at that period. Also they had shared alleles with Eastern European Upper Paleolithic samples like Kostenki14 and Vestonoce cluster, the aforementioned Gravettian culture.
This situation make sense given the common origins of J and I. We could expect that in the deep past they were coming from a population with similar autosomes.
Below in Figure 1 You can see the closest pops to Georgia Upper Paleolithic. As You can see it's more oriented to ancient Europe with high Anatolian and WHG ancestries.
The next puzzle now to solve is the origin of CHG and Iran_Neo. What made them so different from Anatolia forager's/farmers. And the ultimate question were was the common origin of all this folks.
All links are below.