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 the first stone technology has just gone back tens of thousands of years.
Using a type of statistical analysis recently introduced, the researchers estimated the proportion of stone tool artifacts that could be found undiscovered based on what has been excavated so far. In turn, this gives us clues as to how old the remnants of the tool we don’t know yet are likely to be.
These calculations reveal that ancient hominins may have used basic tools from Oldowan 2,617-2,644 million years ago (up to 63,000 years earlier than previous findings suggest), and that slightly more sophisticated Acheulea tools could have been used. having used 1,815-1,823 million years ago (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 at least for me it’s very exciting because it highlights that there are likely to be significant parts of the artifact registry waiting to be discovered.”
The statistical analysis of optimal linear estimation (OLE) applied here has already been deployed to judge how long the species lived before extinction, based on the most recent fossils that have been found. The process has been shown to be reasonably accurate and in this study has been used in reverse.
The oldest stone tools excavated so far by archaeologists are unlikely to be in fact the oldest ever used (experts think many have been lost forever and it is difficult to get away with what is found ), but OLE offers a way to extrapolate from existing artifacts.
While OLE remains an emerging approach in archeology, the researchers behind the new study hope it will be more widely accepted. While the best landmarks are still real finds in the field, these physical discoveries do not tell the full story of what really happened millions of years ago.
“The optimal linear estimation modeling technique was originally developed by me and a colleague to extinction,” says David Roberts, a conservation scientist at the University of Kent.
“It has been shown to be a reliable method for inferring the timing 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 breakthrough. “.
The ability of hominins to break stones and use them for specific purposes opened new horizons for early 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 a “transcendental threshold” in human evolution.
To give you an idea of how long we talked a long time ago, it has been suggested that the first use of stone tools predates the development of thumbs opposable to hominins: we were crushing rocks before we could properly grasp anything.
The oldest stone tools ever found date back 3.3 million years, discovered at the Lomekwi site in Kenya. While there is not enough material on this site to do an OLE analysis, researchers think the use of stone tools could go back even further, although they also admit that their estimates are likely to change as that more excavations and discoveries be made.
“Identifying when hominins first produced Lomekwian, Oldowan, and Acheulean technologies is vital to multiple avenues of research into human origins,” the researchers write in their published paper.
The research has been published in Journal of Human Evolution.