Researchers found a high percentage of burnt remains in the Moli del Salt site in Tarragona, Spain which date back to the end of the Upper Palaeolithic Age some 13,000 years ago.
The study found that the recycling of tools was normal during the Upper Palaeolithic Age and was more common for domestic activities and seems to be associated with immediate needs.
Tools used for hunting, like projectile points for instance, were almost never made from recycled artifacts. In contrast, double artifacts (those that combine two tools within the same item) were recycled more often.
"This indicates that a large part of these tools were not conceived from the outset as double artifacts but a single tool was made first and a second was added later when the artifact was recycled," Manuel Vaquero, researcher at the Universitat Rovira i Virgili, said.
Vaquero said that the burnt artifacts were chosen because "they can tell us in a very simple way whether they have been modified after being exposed to fire".
"In order to identify the recycling, it is necessary to differentiate the two stages of the manipulation sequence of an object: the moment before it is altered and the moment after," Vaquero said.
"The two are separated by an interval in which the artifact has undergone some form of alteration. This is the first time a systematic study of this type has been performed," he said in a Spain-based SINC statement.
The study found that recycling was an economically viable option as well.
"It bears economic importance too, since it would have increased the availability of lithic resources, especially during times of scarcity. In addition, it is a relevant factor for interpreting sites because they become not just places to live but also places of resource provision," Vaquero added.
The study was published in the Journal of Archaeological Science.
