I'd agree that a hunter/gatherer lifestyle may provide a local maximum in some regions, at some points in time. For instance, in Japan, the Jomon hunter/gather

I'd agree that a hunter/gatherer lifestyle may provide a local maximum in some regions, at some points in time. For instance, in Japan, the Jomon hunter/gatherers persisted long after they might have been supplanted by settled agriculturists just across the water. According to Jared Diamond in his later edition of Guns, Germs and Steel, the sheer fertility of Japan's land and seas allowed the Jomon people to maintain a relatively sophisticated culture, mitigating advances which might otherwise have arrived from the fertile crescent via Korea.