Finding out when the first human species first developed and used stone tools is an important task for anthropologists because it was such an important evolutionary step. Remarkably, the projected date of early stone technology was just pushed tens of thousands of years ago.
Using a type of statistical analysis recently introduced, the researchers estimated the proportion of artifacts in stone tools that could be undetected based on what has been unearthed so far. In turn, this gives us clues as to how old the remains of tools we don’t know yet are.
These calculations show that ancient hominins may have used basic Oldowan tools 2,617-2,644 million years ago (up to 63,000 years earlier than previous discoveries suggest), and slightly more sophisticated Acheulian instruments could have been used now. 1,815-1,823 million years (at least 55,000 years earlier than previously thought).
“Our research provides the best possible estimates for when hominins first produced these types of stone tools,” says Paleolithic archaeologist Alastair Key of the University of Kent in the United Kingdom.
“This is important for several reasons, but at least for me it’s the most interesting, because it points out that there are likely to be substantial portions of the artifact record waiting to be discovered.”
The statistical analysis of the optimal linear estimate (OLE) applied here has already been implemented to judge how long the species lived before extinction, based on the most recent fossils that have been found. The process proved to be reasonably accurate and, in this study, was used in reverse.
It is unlikely that the oldest stone tools that archaeologists have unearthed so far are actually the oldest that have ever been used – experts believe many are lost forever, and dating what is found is difficult. – but OLE provides a way to extrapolate from existing artifacts.
While OLE is still an emerging approach in archeology, the researchers behind the new study hope it will become more widely accepted. Although the best benchmarks are still real discoveries in the field, these physical discoveries do not tell the full story of what actually happened millions of years ago.
“The optimal linear estimation modeling technique was originally developed by me and a colleague so far with extinctions,” says conservative scientist David Roberts of the University of Kent.
“It has proven to be a reliable method of deducing the time of species extinction and is based on the moments of the last observations, so applying it to the first observations of archaeological artifacts was another interesting discovery.”
The ability of hominins to remove stones and use them for specific purposes opened new horizons for the first humans: in terms of what they could hunt, what they could build, how they could work with food and materials, and so on. It has been called the “important threshold” in human evolution.
To give you an idea of how long ago we were talking, it was suggested that the first use of stone tools predates the development of thumbs opposable to hominins: we crushed the stones before we could properly grasp something.
The oldest stone tools ever found date back to 3.3 million years ago, discovered at the Lomekwi site in Kenya. Although there is not enough material on this site to perform an OLE analysis, the researchers believe that the use of stone tools could go even further – although they also admit that their estimates will change as new discoveries are made. and discoveries.
“Identifying when hominins first produced Lomekwian, Oldowan, and Acheulean technologies is vital to several ways of researching human origins,” the researchers write in their published paper.
The research was published in Journal of Human Evolution.