Abstract :
[en] Lithic industries from Papua New Guinea surprised the first Western archaeologists who excavated on this Northern part of Sahul. With a few exceptions, they are often characterized by a lack of standardization and simple operating sequences which lasted with little change for thousands of years. As in Southeast Asia, the region where the first colonizers of New Guinea came from, prehistorians attempted to explain these particularities by the “Bamboo Hypothesis”: if stone tools are scarce and often result from short or simple manufacturing sequences, it is because they were intermediary implements used to make bamboo tools. These would have been varied, at the center of the economy of an “Age of Bamboo”.
Here we present the functional analysis of a very unique polisher from Kiowa. The site is located in the highlands of Eastern New Guinea and was occupied from 12 000 BP. The polisher was found in layer 2, just above layer 3, dating to 5324–5707 cal BP. This exceptional tool presents a large, pointed groove which was interpreted as resulting from the manufacturing of a bamboo spear. We tested this hypothesis by conducting use-wear and residue analyses, using optical microscopes, Hirox, Scanning Electron Microscope, EDX analysis, residue extraction and PXRF. Our results show that it was actually a multi-function tool that was used for four different activities. One of them was the processing of flexible but silica-rich plants, such as the grasses that are used to make skirts nowadays in the region. In the very groove, use-wear points to the working of a semi-hard organic material such as bone or wood. The presence of a wood residue tips the balance in favor of the latter. The morphology of the groove also perfectly matches the shapes of experimental polishers we used to make wooden spears. This discovery echoes the finding of Casuarina wooden tools including burrowing sticks at the site of Kuk, on the same islands, in layers dating to 4600 BP to 2300 BP. In New Guinea, like in Southeast Asia, recent archaeological discoveries made possible thanks to use-wear and residue analyses open the Bamboo Hypothesis and show that a plant technology indeed existed during Prehistory, but that it was diverse and not focused exclusively on bamboo tools.
