Our ancestors made wooden constructions at least half a million years ago, much earlier than previously believed. The discovery at the archaeological site of Kalambo Falls, in Zambia, of two artificially altered and superimposed trunks, evidence that the inhabitants of these lands were capable of modifying nature for their own benefit hundreds of thousands of years before the appearance of Homo Sapiens. Until now, evidence of the use of wood at that time was limited to lighting fires and using tools.
The British team of archaeologists who discovered the structure have not been able to elucidate its purpose. It could be an elevated platform, a walkway or the foundation for a home. However, they believe that their discovery may change the way scientists view our predecessors. “Forget the 'Stone Age' label,” says Larry Barham, an archaeologist at the University of Liverpool (United Kingdom) and leader of the study, “these people used their intelligence, imagination and skills to create something they had never seen before, something that had never existed previously [...], they were more similar to us than we thought," he asserts.
The upper trunk of the construction exhibits a notch in which researchers have found “evidence of cutting and scraping,” as stated in an article published this Wednesday in the journal Nature. This artificial deformation of the wood allows it to fit with the lower trunk, forming a single structure that could not have occurred naturally. Additionally, both pieces of wood show cuts made with stone tools.
Together, the marks constitute sufficient evidence to conclude that a group of hominins (the group of upright primates, of which Homo Sapiens is the only representative today) worked and altered the shape of the wood to make the first construction of our ancestors of the that is recorded.
Scientists have dated the structure by analyzing the sand in which the logs were buried. Using luminescence techniques, they have been able to estimate that the last time the Earth was exposed to sunlight was about 476,000 years ago. By then, the bank of the Kalambo River was surrounded by extensive forest, so those who built the structure had perennial sources of water and food.
“The availability of forest resources and a permanently high water table created a habitat conducive to sustained occupation,” the authors conclude in the article, challenging the hitherto established idea that the tribes of the Stone Age, known scientifically as the Pleistocene They were nomads.
The evidence available so far, based on a very small amount of well-preserved remains, had revealed that our Pleistocene ancestors used wood to light fires or as tools (they made spears and digging sticks, for example). However, its use in construction was completely unknown.
The reason for such limitations is how poorly wood is preserved, which requires unique conditions to withstand the passage of time without rotting. At Kalambo Falls, the samples were buried in sand and submerged at the bottom of the river, isolated from sunlight and contact with air, in unique conditions that have allowed their conservation.
Once excavated, the remains degrade quickly, so their analysis is usually “a race against time,” explains in an analysis of the scientific article Annemieke Milks, an archaeologist at the University of Reading, in the United Kingdom, who has not participated. on the research. “Studies like this highlight the role of the most humble material in human history, and simultaneously reveal when people began to structurally alter the planet for their own benefit,” she concludes.
The British team has also recovered four wooden tools from a second hominin occupation, between 390,000 and 324,000 years ago. The materials found include a wedge, a digging stick, a cut log and a branch with samples, which the researchers say constitutes “an unexpected early diversity of forms.”
Together, the remains excavated from the site “allow us to glimpse the ability to create a construction environment by hominins until now perceived as mobile foragers with limited technological diversity,” they conclude in the Nature article.
