[dr_dshiv]

I wonder how this lower Volga group interacted with the earliest known civilization (5000-3000 BCE), in modern day Ukraine, the Cucuteni–Trypillia [1].They had cities with between 20-40k people that overlapped with the Yamnaya people’s discussed in the article (3500-2500 BCE).

They had agriculture as well as wheels for transportation and pottery. All predating middle eastern civilizations.

They also burned down their own cities every 50-100 years.

This culture was in constant threat from the nomads of the steppe and they learned to live in large groups as protection. This hypothesis is discussed at the end of a recent publication [2: p219-220].

[1] https://en.wikipedia.org/wiki/Cucuteni%E2%80%93Trypillia_cul...

[2] https://pure.tudelft.nl/ws/portalfiles/portal/144861667/enig...

[mjfl]

how do archaeologists know they burned down their own cities? One would expect the more neutral statement 'Their cities were burned every 50-100 years".

[acjohnson55]

My wild guess would be the coexistence of human remains and maybe other non-structural debris with burn layers.