Researchers at Tokyo Metropolitan University have provided fascinating insights into the woodworking technology of prehistoric humans. By crafting replica Stone Age tools and subjecting them to various tasks, the team discovered that different activities leave distinct traces on the tool's edge. Combining macroscopic and microscopic evidence, they were able to differentiate tools used for wood-felling from those used for other purposes. This criterion could potentially revolutionize our understanding of when early humans began utilizing timber.
While early Stone Age artifacts suggest rudimentary use of wood for tools like spears, later periods reveal far more sophisticated woodworking techniques. Mesolithic and Neolithic artifacts indicate the construction of houses, canoes, bows, and wells, showcasing the evolution of woodworking technology. Polished stone axes, in particular, demonstrate advancements in crafting complex wooden instruments.
Traditionally, advanced wood-processing technology has been associated with the Neolithic age, approximately 10,000 years ago. However, ground stone axes have been unearthed from periods predating this era. Sites across Australia and Japan have yielded ground edge artifacts dating back to Marine Isotope Stage 3, around 60,000–30,000 years ago, raising questions about their early usage.
To investigate, Assistant Professor Akira Iwase and his team embarked on a hands-on approach, crafting replicas of tools from the Early Upper Paleolithic age. Using knapping and grinding techniques available at the time, they meticulously polished the edges and attached handles to create adzes, axes, and chisels.
The researchers then conducted 15 different activities with the tools, including tree-felling, hide-processing, and butchering, as well as non-use events like carrying and trampling. They meticulously examined the edges for both macroscopic and microscopic traces, finding distinctive fractures from tree-cutting impacts and microscopic friction marks from wood interaction.
By combining these findings, the team could reliably determine whether the edges were used for felling trees. If similar traces are found on artifacts from Marine Isotope Stage 3 sites, it would suggest that humans had mastered woodworking technology much earlier than previously thought.
This discovery has the potential to reshape our understanding of stone tool use by Ice Age humans and the spread of such technology across different environments. It highlights the ingenuity and adaptability of early humans in utilizing natural resources to advance their societies.
Source: Tokyo Metropolitan University