The Stone Age inhabitants of southern Africa used at least 200,000 years ago a mixture of herbs and ash in their beds for comfort and to repel pests.
These beds served as a resting area and as a space for daily work, thanks to the presence of ashes and herbs, they allowed to repel insects. The discovery, published inScienceIt is the oldest recorded human use of grass beds, surpassing previous evidence in more than 100,000 years.
This finding also confirms the ability of Stone Age humans to organize and order space for daily tasks, using grasses -Panicum maximum, in the case of the Border Cave - to build beds, rest and work areas. In turn, it illustrates the knowledge that these inhabitants had about ashes as insect repellants, demonstrating a complex behavior in problem solving.
Because plant matter is often preserved in poor archaeological conditions, the evidence of using plants for anything other than food is scarce and difficult to interpret. The oldest known use of grass beds - before Border Cave - dates back to 77,000 years ago, when prehistoric humans in Sibudu (KwaZulu-Natal, South Africa) used layers of reeds interspersed with medicinal plants and ash to cover living spaces in rocks.
Lyn Wadley, principal investigator of the work at the Institute for Evolutionary Studies at the University of the Witwatersrand (South Africa), considers that these practices began long before this previous evidence: “200,000 years ago, close to the origin of our species, humans used fire, ash, and plants to keep camps clean and free of pests. This simple strategy that we see in Border Cave offers us a glimpse of the lifestyle of our ancestors”. The Border Cave contains a well-preserved record of intermittent human occupation spanning almost 230,000 years.
An example of complex human behavior
Irene Esteban and Paloma de la Peña, Spanish co-authors of this study also at the University of the Witwatersrand, explain that this behavior "can be considered as proof of an analogical reasoning that implies knowing two aspects of reality, which are compared and analyzed together”. In the case of the inhabitants of Border Cave, they were aware of a problem: discomfort. For this they looked for a solution, which was to collect herbs in large quantities and create rest areas.
It is possible that the grasses, used by the ancient inhabitants of Border Cave and still growing near this cave, were infested by disease-carrying ticks, which bite humans. Therefore, Esteban and De la Peña indicate that these humans “realized that the ashes paralyze the ticks' breathing apparatus" O well "there is a lower incidence of insects when they use the ashes as the base of their beds”.
This behavior would have its origin in the burning of old or disused beds, as part of the maintenance of the living areas, in which they would burn the old herbs and leave the ashes at the base to make new beds, according to the researchers.
Wadley et al. “Fire and grass-bedding construction 200 thousand years ago at Border Cave, South Africa”.Science (August 14, 2020).