Complex interaction over Caucasian range.

 Complex interaction over Caucasian range.

We have now sufficient DNA from both south and north of Caucasus to draw at last the contours of migratory events that shaped the pre Bronze Age history of Caucasian range. So lets make a summary of them.

If we skip the Paleolithic Mesolithic periods we have those events.

Around 5500-5000 BC Farmers from.Kura Araxes basin, almost certainly related to Shulaveri culture cross the Caucasus and venture to north. Even though its still contested by some but I have little doubt that zoological data will support the idea that pastoralism appears in East Europe due to this event. It spread rapidly to north toward Volga, then slightly later toward Ukraine. Those are the earliest kurganic cultures in East Europe that can be linked to IE people.

However the two most frequent haplotypes associated with pastoralism in East Europe are the R1b-V1636 and I2-L699 of local origin (EHG and UHG). Occasionally we see some cases of J2 and J1. The most remarkable is the J2b2b from Eneolithic Moldova which is from the same branch as the Shulaveri Y DNA from Menresh tepe in Azerbaijan. The J2b2a1-L283 that later expanded with Yamnaya also might be from Shulaveri.

Why despite important autosome changes in East Europe we dont see a similar change in Y DNA is a subject beyond the scope of this post.

Around 4300BC there is a migration from north to south. Not much was known about this migration before ancient DNA but given the apparition of R1b-V1636 in the south and also kurganic burials alongside local jar butials, there is little doubt that those were some northern pastoralistic groups that ventured to south. Their migration to south is apparently not massive and is not associared with mass violence. Quite contrary they became part of so called Chaff faced ware groups present all over the Highlands and South Caucasus.

The steppe ancestry in Areni in Chalcolithic period is the best proof of this migration.

Around 3900-3800BC a new group moves to north, once more apparently via Daghestan and plays a role in the formation of Maykop culture. The reason why I believe in a migration via Daghestan is that none of haplotypes found in Maykop culture was present in ancient Georgia. Those are the L2, T1a3, J2-P81. Also a mass migration of CFW people via Georgia would cause a strong dilution of CHG ancestry for which we dont see any evidence, especially in West Georgia.

Maykop was a complex story, people from Central Asia also played a role in Maykop culture introducing the haplogroup Q1. Maykop is not directly ancestral to Yamnaya even though it probably had some cultural influence. Maykop Novosvobodnaya had G2a2a, in theory if could be a result of a distinct migration via central Caucasus. However the data is still insufficient for definitive conclusions.

Around 3600BC another group migrates from south to north. Those are the Kura-Araxes culture people associated with J1-Z1842 haplotype. This new event harms the interests of Maykop people. In most likelihood it moved to north via central regions of Caucasus. Via modern Mtskheta-Mtianeti or Kakhetia region. The massive presence of J1-Z1842 in north Caucasus leaves little doubt that it is associated with Nakh-Daghestani speakers there. Meanwhile in the steppe region near Azov sea a Proto Yamnaya group prepares to expand around 3500BC. It is associated with R1b-Z2103. This group will not move immediatly to south. Only after 2500BC. Even though Yamnaya people will create an offshoot in North Caucasus known as North Caucasian culture or Kubano Tersk.

The map shows two way interactions between north and south over eastern pass. The genetic history of western pass in Caucasus is different. It was more isolated and had less impact.