Characterisation of the use-wear resulting from bamboo working and its importance to address the hypothesis of the existence of a bamboo industry in prehistoric Southeast Asia

Prehistoric stone tools discovered in Southeast Asia contrast with what is found in the rest of the world: they are simple and their production techniques remained unchanged for millennia. To explain these unique characteristics, some scholars offered what is called the “bamboo hypothesis”: if SE Asian stone tools are simple it would be because they were actually used to manufacture more complex implements made of bamboo. This hypothesis relies on a series of indirect evidence, among which the fact that use-traces occurring on the stone tools result from plant processing. These traces are often interpreted as due to bamboo working although in the absence of an adapted reference collection such a precise diagnosis is impossible to make. A fundamental question remains to be addressed: is it possible to distinguish the working of bamboo from the one of other plants based on the traces they produce? To answer this, we carried out several experiments, grounded on ethnoarchaeological observations, which involved 15 tropical plant taxa, including 3 bamboo genera and conducted microscopic use-wear analysis of the experimental tools. Our results show that the use-wear created by processing mature bamboo is well-developed and can be defined through a set of criteria. Altogether they distinguish bamboo wear from the one produced by other plants, although some overlapping exists. Our results can be used as a reference to which the traces on archaeological stone tools can be compared in order to determine whether they were really used to process bamboo and to what extent.