Simply because there is no direct evidence of farming at this site, doesn't mean these megalithic structures were completed by semi-nomadic tribes. Just immagine how many men it would take to quarry and move one multi-ton stone up that hill to this location. There is no way that a hunder-gather village of a few hundred peoples could expend that type of energy, and support ongoing improvements over generations without a localized, established food supply.
Something is not right. This message is just to keep things from messing up down the road