I have gotten a lot of crap from my enemies for being on the Academia.edu site in the first place, but really anyone can join.
The following was posted by one of the reviewers in an Academia session by one of the leading lights of the Basque-Caucasian theory. As you can see, the mythological and multiple lines of genetic evidence are starting to pile up pretty nicely too. This is neat stuff if you are interested in the Basque-Caucasian link in addition to work going on into the remains of the Neolithic Farmers who were subsumed in the Indo-European waves. It turns out there is quite a bit left in different parts of Europe, especially in terms of Neolithic Farmer mythology.
From a discussion among academics and independent scholars on a paper on the Basque-Caucasian Theory in Historical Linguistics during a session in on Academia:
I am not a linguist but interested in the topic as it proposes a linguistic correlation between Caucasic languages and Basque, as it parallels my own current research on reconstructing European Paleolithic mythologies using ethnographic analogies constrained by on archaeogenetics and language macrofamily correlations.
Tuite (2006, 2004, 1998, 1997) has pointed out the hunter-gatherer beliefs and myth motifs shared across a ‘macro-Caucasic’ area to the Hindu Kush and into Western Europe. Basque deities Mari, Sugaar, and Ama Lurra and their associated mythologems have striking similarities to the macro-Caucasic hunter mythologies (not found in Finno-Ugric or Middle Eastern ancient mythologies.)
I am currently writing a paper identifying many examples of Southern/Western Gravettian art in Italy, Spain, southern France that appear to depict imagery only explicable by analogy to Macro-Caucasic religious myth and ritual.
With respect to mtDNA fossil genetics, three skeleton samples are from Paglicci Cave, Italy, ~25 cal BP: one is macro-N-mtDNA (homeland Caucasus/Caspian/Iran; currently highest frequencies Caucasus, Arabia), and two skeletons, RO/HV-mtDNA (homeland northern Middle East; currently highest frequencies, Basque, Syria, Gilaki, Daghestan).
During the later Magdalenian another diffusion occurs apparently by a similar route: HV4-mtDNA emerges in Belarus-Ukraine (~14±2 ka) and under Late Glacial Maximum HV4a (~13.5 ka) moves south and splits in the three refugia: southern Italy, southern Russia (HV4a1, ~10 ka), the Middle East (HV4a2, ~9 ka), and Basque area (HV4a1a, ~5 ka, suggesting full emergence of distinct Basque culture and language), (Gómez-Carballa, Olivieri et al 2012).
These studies further support the existence of a Macro-Basque-Caucasic mythological stratum as well as shared language substrate.
The cutting-edge liberal theory is that Basque (and some other odd far-flung languages) is part of the Caucasian language family. In other words, at one time, the Basques and the peoples of the Caucasus like Chechens were all one people.
What this probably represents is the ancient Neolithic farmers who covered Europe before the Indo-European invasion replaced almost all of the languages of Europe. All that is left is Basque and the peoples of the Caucasus. Everything in between got taken by IE except for some late movements by Uralic and Turkic speakers. Up in the north, the Lapp Uralic speakers are, like Basques, the last remains of the Neolithic farmers. The Sardinians also an ancient remaining group of these people, but their language has been surmounted recently by a Latinate tongue.
As it turns out, the Basques and Caucasians also share a number of cultural similarities. There are also some similar placenames. And there is some good genetic evidence connecting the Basques with the Caucasian speakers.
It’s all there, but the conservatives are balking, to put it mildly, about linking Basque with the Caucasian languages.
I have long believed in this theory.
I read a book over 20 years ago comparing Basque to the Caucasian languages and a few other distant tongues and thought the case was proved even via overkill by the book. And recent work is so super that one wonders why the conservatives are still winning. I feel that the link between Basque and the Caucasus languages is now proven to an obvious and detailed degree.