Food was a central part of island life, since each settlement consisted of small family groups gathered around a cook house containing at least one earth oven.
Earth ovens are among the most common things archaeologists look for at an anthropological dig, as they are one of the key indicators of human civilization and static society.
It has been suggested that the ditch was in fact used to hold a series of earth ovens, or cooking pits, to prepare food for workers in a nearby quarry.