Neolithic Revolution as irrigation and deforestation which allowed the production of surplus food. Other developments found very widely are the domestication of animals, pottery, polished stone tools, and rectangular houses. These developments, sometimes called the Neolithic package, provided the basis for centralized administrations and political structures, hierarchical ideologies, depersonalized systems of knowledge (e.g. writing), densely populated settlements, specialization and division of labour, more trade, the development of non-portable art and architecture, and property ownership. The earliest known civilization developed in Sumer in southern Mesopotamia (); its emergence also heralded the beginning of the Bronze Age. The relationship of the above-mentioned Neolithic characteristics
Three-age system two Pre-pottery Neolithic periods, she concluded, A and B. Moreover, the PPN had been discovered at most of the major Neolithic sites in the near East and Greece. By this time her personal stature in archaeology was at least equal to that of V. Gordon Childe. While the three-age system was being attributed to Childe in popular fame, Kenyon became gratuitously the discoverer of the PPN. More significantly the question of revolution or evolution of the Neolithic was increasingly being brought before the professional archaeologists. Danish archaeology took the lead in defining the Bronze Age, with little of the controversy