A bunch of Japanese scientists built themselves replicas of tools dating back to the Early Upper Paleolithic. They then used those tools for tasks for which they might have been used back in the day. Resultantly, the tools wore out and had cracks on them. A recent article in the Journal of Archaeological Science concluded that if similar signs were found on genuine Stone Age tools, then it would be proof that humans have been using tools significantly earlier than previously perceived.
The general concept of using tools in human history began with the manufacture of cruder tools like spears and throwing sticks in the early Stone Age. However, as an understanding of these tools was built, humans shifted to improved tools and used them to make canoes, bows, wells, and houses. The consensus is that this use began around 10,000 years ago, but archaeologists have found artifacts with ground edges dating from around 30,000 to 60,000 years.
Akira Iwase, who is from Tokyo Metropolitan University, and her colleagues built tools for themselves using raw materials available for approximately 38,000 to 30,000 years. The raw materials used to make the tools were semi-nephrite, hornfels, and tuff rocks. The tools brought back to life were adze-types, axe-types, and chisel-types.
Scores of experiments were conducted using the tools. The axe type was used to cut trees in northern Japan and Tokyo Metropolitan University’s surroundings. The axe-type and adze-type were then used to dig out a canoe and craft wooden spears. The adze and chisel types used scrap flesh and grease from fresh and dry hides of deer and boar. Apart from using the tools and then looking for signs of wear and tear, the team also resorted to non-use methods to examine the impact that might have had on the tools. For instance, transporting tools, carrying them in small leather bags, and leaving them on the ground can have a micro/macroscopic impact on the tools.
The results: The team concluded that examining only the macroscopic signs of wear and tear was insufficient to determine whether a tool was used at that age. Similar signs can appear on a tool for different reasons; however, when both micro and macroscopic impacts were assessed, a more conclusive result was derived as to when and for what purpose the tools were used.