The oldest repellents can be about 200 thousand years old. The scientists came to that conclusion, studying the unusual compositions of conditional ridges that our distant ancestors used for personal needs. In cultivating certain plants, they used certain species with a certain flavor. The property of the aroma was that they could scare the harmful insects away with the smell of leaves.
Such conclusions were made after chemical analysis of the fossilized remains of plant particles that form the bed. In addition to the fact that the ancient ancestors used certain plants as repellents, the scientists are almost sure that ash brought the same benefits.
It is also present in the border areas of the ridges. Such assumptions were made after a group of researchers examined the state of the cave in South Africa and the area at its entrance. It had an interesting feature that was in a zone with a preserved grass cover, which is at least 200 thousand years old.
It may indicate that the ancient inhabitants of Africa about 200 thousand years ago not only slept on a grass bed, but also grew it on their own. At the same time, some types of plants were used to scare the harmful and dangerous insects away.
An archaeologist Lyn Wedley from the University of the Witwatersrand in Johannesburg chemically analyzed the remains of one of these beddings. The ashes scattered under the tied tufts of grass could be used to repel crawling, biting insects. In addition, laboratory analysis revealed the smallest pieces of burnt wood in the bedding that was most likely used for sleeping.
They all contained fragments of camphor leaves. That aromatic plant is often used in the modern world as an insect repellent. Prior to that, the researchers found particles of leaves of sedge, ash and some aromatic plants in such residual pieces of litter. Their age is about 77 thousand, and they were found in the Sibudu rock formation in South Africa.