The local folklore recorded by anthropologist Thor Heyerdahl told of a two-tier society during the statue-building era, and how there were two rebellions (perhaps during times of privations of some sort) the second ending in the near-annihilation of "the long-ears" by "the short-ears". The location of the long-ears' fastness is still known, the digs there confirmed one element of the tale, and overall this is consistent with the overall history, prehistory, and folklore of the Polynesians throughout the Pacific, and for that matter, with humans in general.
Thanks, I have not followed that story at all. But it is fascinating that in the 1960s I was sold a story that contradicted Heyerdahl without having ever heard his synthesis of accounts. All I knew of him was Kon-Tiki. It shows how thoroughly the “greenie” depopulation message permeated media even then. It makes a nice anecdote for the work I’m doing now.