I susepct a mild varient of the AAH is probably true. There is a problem that needs solving: why can humans swim (and many do so for fun), while other hominoids avoid water?

I doubt if there was a ever a time in prehistory where the ancestors of humans were all living an aquatic lifestyle, but there must have been many occasions where a band of pre-humans lived on the shores of a lake or ocean. Some of these individuals would have used the water to find food or escape from predators, and I hypothesize that this happened often enough that evolution would have changed our psychology and anatomy accordingly.