Study suggests prehistoric humans “recycled” tools to preserve memory of their ancestors
Prehistoric humans were collectors by nature and culture, TAU researchers saySupport this research
After examining flint tools from one layer at the 500,000-year-old prehistoric site of Revadim in the south of Israel’s Coastal Plain, Tel Aviv University (TAU) researchers surmise that prehistoric humans were collectors by nature and culture. The study suggests that they had an emotional urge to collect old human-made artefacts, mostly as a means for preserving the memory of their ancestors and maintaining their connectedness with their place and time.
The study was led by PhD student Bar Efrati and Professor Ran Barkai of the Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures at TAU’s Entin Faculty of Humanities. The paper appeared in Scientific Reports.
Efrati explains that stone tools with two specific lifecycles have been found at prehistoric sites all over the world, but the phenomenon has never been thoroughly investigated. In the current study, the researchers focused on a specific layer at Revadim, a large, open-air, multi-layered site in the south of Israel’s Coastal Plain, dated to about 500,000 years ago. The rich findings at Revadim suggest that this was a popular spot in the prehistoric landscape, revisited over and over again by early humans drawn by an abundance of wildlife, including elephants. Moreover, the area is rich with good-quality flint, and most tools found at Revadim were in fact made of fresh flint.
“The big question is: Why did they do it? Why did prehistoric humans collect and recycle actual tools originally produced, used, and discarded by their predecessors, many years earlier?” Efrati says. “Scarcity of raw materials was clearly not the reason at Revadim, where good-quality flint is easy to come by. Nor was the motivation merely functional, since the recycled tools were neither unusual in form nor uniquely suitable for any specific use.”
The key to identifying the recycled tools and understanding their history is the patina, a chemical coating which forms on flint when it is exposed to the elements for a long period of time. A discarded flint tool that lay on the ground for decades or centuries accumulated an easily identifiable layer of patina, which is different in both color and texture from the scars of a second cycle of processing that exposed the original color and texture of flint.
In the current study, 49 flint tools with two discrete lifecycles were examined. Produced and used in their first lifecycle, these tools were abandoned, but years later, after accumulating a layer of patina, they were collected, reworked, and used again. The individuals who recycled each tool removed the patina, exposing fresh flint, and shaped a new active edge. Both edges, the old and the new, were examined by the researchers under two kinds of microscopes, and via various chemical analyses, in search of use-wear marks and/or organic residues. In the case of 28 tools, use-wear marks were found on the old and/or new edges, and in 13 tools, organic residues were detected, evidence of contact with animal bones or fat.
Surprisingly, the tools had been used for very different purposes in their two lifecycles: the older edges primarily for cutting, and the newer edges for scraping (processing soft materials like leather and bone). In addition, the tools were reshaped in a very specific and minimal manner in their second lifecycle, preserving the original form of the tool, including its patina, and only slightly modifying the active edge.
“Based on our findings, we propose that prehistoric humans collected and recycled old tools because they attached significance to items made by their predecessors,” Professor Barkai says. “Imagine a prehistoric human walking through the landscape 500,000 years ago, when an old stone tool catches his eye. The tool means something to him – it carries the memory of his ancestors or evokes a connection to a certain place. He picks it up and weighs it in his hands. The artifact pleases him, so he decides to take it ‘home’. Understanding that daily use can preserve and even enhance the memory, he retouches the edge for his own use, but takes care not to alter the overall shape – in honor of the first manufacturer.
“The prehistoric human may be likened to a young farmer of our own time still plowing his fields with his great-grandfather’s rusty old tractor, replacing parts now and then, but preserving the good old machine as is, because it symbolizes his family’s bond with the land. In fact, the more we study early humans, we learn to appreciate them, their intelligence, and their capabilities. Moreover, we discover that they were not so different from us. This study suggests that collectors and the urge to collect may be as old as humankind.”
Dr. Flavia Venditti from the University of Tubingen in Germany and Professor Stella Nunziante Cesaro from the Sapienza University of Rome, Italy, also collaborated on the study.