Basically the authors concede that everyone makes these stone gyoza, but claim that the reduced variation in the tool within this region means increased communi

Basically the authors concede that everyone makes these stone gyoza, but claim that the reduced variation in the tool within this region means increased communication of tool-making is associated with this era of increased tool-production. The data seem to bear this out, but they do not really address differences in materials or differences in morphology of the user. Arguably valid reasons for ignoring both of these are given, 1) that in a limited view material has little impact and material was not selected for within populations who could have traded or traveled for similar materials, and 2) (this may have just been implicit) these are repeatedly indicated to be backed tools. This means they were designed to be mounted in a carrier tool (typically wood or bone that did not survive to present day). Like a safety razor blade, you don’t hold it in your hands.