The Basque tourist board would say that, but, apart from being the oldest living language in Europe, it’s unverified — and unverifiable — hype. Nobody knows, and never will, what language cave men spoke and it’s certainly unlikely to be “at the seeds of articulate language”. Some people do talk nonsense but in this case I don’t suppose they really believe it.
Yes I do wonder on what grounds these “renowned linguists and historians” believe that the Basque language can be the “direct descendant of the language spoken by the dwellers of the caves of Altamira, Ekain or Lascaux” But the uniqueness of the language is not in question. It seems to be unrelated to any Indo-European or Romance languages and is considered to be a “language isolate”. No doubt in part a product of the relative physical isolation of the region
It is like the Romance Languages, like French, Spanish, Italian and Portuguese, they did not come from Latin, they came from a language spoken by the peasants of Rome. The linguistic Yvez Cortez has written a book proving that the French and the Spanish ( Castillian ) did not originate from the Latin language