I've scoured papers, forums and blogs, and weirdly to no one does it seem important that losing 40,000 square miles* around the time of a great admixture event seem worth mentioning.
A vast plateau of swamps, sand dunes, peat bogs, deserts and alluvial plains wiped out in a matter of generations. And the people? Can we assume people lived there as most humans of our past lived within a few miles of a major water feature? Then came salinization.
Does anyone think it might be important to how two peoples crash into each other?
|"I'm still confused BBB, please explain"|
* Compilation of geophysical, geochronological, and geochemical evidence indicates a rapid Mediterranean-derived submergence of the Black Sea's shelf and subsequent substantial salinification in the early Holocene
Update 1. See my comment below.
Potsherds from a few vessels with Cardium decoration were recently found in old collections of some Neolithic sites of the Northern Black Sea area. A good samples of the valves of brackish water ostracods were discovered in the raw material in most of these vessels. This could indirectly indicate the presence of Neolithic settlements with Cardium pottery on what is now a flooded region of the northern Black Sea coast. Some data show that its inhabitants could have been the initial source of the Neolithisation of neighbouring inland territories. Thus, the whole local Neolithic in the region is interpreted as a northeastern branch of the Mediterranean Neolithic with Impresso and Cardium pottery
Update 3. FrankN wrote this in 2019 "How did CHG get into Steppe_EMBA? Part 2: The Pottery Neolithic" He poopoos on Dmytro Gaskevych's idea that Mediterrean-based Impresso folks settled the area based on adna. Given that Circum-Mediterrean Impresso peoples are probably very heterogenous, I think fairly weak argument. It's a matter of which enclave produced the stream of settlers.
Reading further though, some agreement on the presence of CHG in the North Black Sea. Very reason to think it was more prominent across the ancient northern Black Sea, than just the 1/3 northeasternly portion where we know it was abundant.