 This effect was often achieved by encapsulating a single corpse in a basic pit, surrounded by an elaborate ditch and drain.Over-ground commemoration is thought to be tied to the concept of collective memory, and these early tombs were likely intended as a form of ancestor-worship, a development available only to communities that had advanced to the stage of settled livestock and formed social roles and relationships and specialized sectors of activity.In Neolithic and Bronze Age societies, a great variety of tombs are found, with tumulus mounds, megaliths, and pottery as recurrent elements.