Pontisto 
Civilisations by definition plunder and exploit their natural habitat and are careless toward sustainability of the very environment their longterm survival depends upon.
On the other hand, "savages" (latin: people of the woods) live in harmony and balance as integral part of their worlds, making them ideal candidates for eon long existences and survival.
So, a more intriguing question is, would any of these "savagations" want anything at all to do with us? And would we not be morally obligated to respect their equilibrium ... including the idea that there are others beside them.