other point about ancient Rgvedic clans in the steppes. If your theory is right, that Rgvedic clans left India around 9000 years ago and maintained a close knit society and did not intermingle with any local populace and later returned to India. This hypothesis goes against what you are advocating. If these Rgvedic clans did not intermingle with the steppe people, then they could not have left any genetic imprint on the steppe population and hence cannot account for shared genetic ancestry between the populations in the steppe, India and Europe.
Brilliant.
Couldn't have put it better myself.
My cryogenic endogamous 2000 year old salmon swimming back to mate ....
Cheers, Doc

