Masters of the Pacific Coast

I’ve been following the Masters of the Pacific Coast mini-series on catch-up TV.

So we’re told that the original settlers of the Pacific Coast of Canada and the north western USA managed to develop a complex social structure, but without inventing agriculture, which would have been less efficient than a hunter-gathering lifestyle in that environment. However isn’t it equally possible that they were originally survivors of a disaster which destroyed an ancient civilisation, thus already having both a social structure and agriculture, but lost or discarded the agriculture skills because they were no longer needed? As a coastal culture, they could have arrived by sea, thus attesting to the maritime capabilities of the civilisation which plotted the ancient maps. The presumed late Ice Age time of arrival fits well with the theory explored in The Atlas Legacy.