The Origins of Ground-edge Axes: New Findings from Nawarla Gabarnmang, Arnhem Land (Australia) and Global Implications for the Evolution of Fully Modern Humans

The grinding of stone to make sharp cutting edges did not evolve with the emergence of biologically modern humans in Africa, but late in the Pleistocene at the completion or nearcompletion of the Out-of-Africa 2 migration. Here we discuss the earliest securely-dated fragment of ground-edge axe from Australia, dated at 35,500 cal. bp, an age slightly older or comparable to the earliest ages for edge-grinding from the Pacific Ocean's western seaboard. In this region ground-edge axes did not evolve with the emergence of agriculture, nor for the clearance of forests, but, rather, as socially mediated technology, part of the development of symbolic storage that is the hallmark of the evolution of cognitively modern humans at the geographical end, during, or following, Out-of-Africa 2.