We know the history of medicine stretches deep into prehistory, but its exact origins remain mysterious. Simple surgery dates back to the stone age, and now there's evidence of basic medical knowledge that dates back to the dawn of humanity.
That's the finding of an archaeological team led by Professor Lyn Wadley of the University of the Witwatersrand in Johannesburg, who recently uncovered evidence of plant bedding at the Sibudu rock shelter in South Africa. This is bedding both in the gardening sense of the temporary placement of plants in simple containers, and in the sense that the ancient humans probably slept on them as mats. These bedding sites date to between 77,000 and 38,000 years old, with the oldest examples particularly well preserved.
The bedding consists of about a centimeter-thick layer of compacted stems and leaves from various sedges and rushes, with a thin layer of leaves on top of them. These leaves display some pretty nifty knowledge of the local flora on the part of the ancient humans - these particular leaves have insecticidal chemicals, and would have been perfect for keeping mosquitoes away and protecting the rest of the bedding.
Most of the plants underneath are associated with herbal medicine, suggesting the bedding was perhaps used as a way to keep useful plants close at hand, as well as simply providing a soft surface to make their shelter more comfortable. Microscopic analysis of the bedding shows humans regularly replaced and replenished the plants through the course of their occupation of the site. Professor Wadley explains:
"The selection of these leaves for the construction of bedding suggests that the early inhabitants of Sibudu had an intimate knowledge of the plants surrounding the shelter, and were aware of their medicinal uses. Herbal medicines would have provided advantages for human health, and the use of insect-repelling plants adds a new dimension to our understanding of behaviour 77,000 years ago. The inhabitants would have collected the sedges and rushes from along the uThongathi River, located directly below the site, and laid the plants on the floor of the shelter. The bedding was not just used for sleeping, but would have provided a comfortable surface for living and working."
This is just one of a number of remarkable discoveries of early human activity at the site, which has previously included early evidence of bow and arrow technology, snare and trap hunting, and even the production of simple glue for stone tools.