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