Experiment recreating Neanderthal adhesive revealed potential to heal wounds
An early Neanderthal glue used to make tools may also have been an antibiotic of choice for hominids. A new study on the sticky substance, published March 18 in PLOS One, raises the possibility that it could have been used to treat wounds and prevent skin infections, such as those caused by Staphylococcus aureus.
Neanderthals burned birch bark to create a tar that they used to attach stones to weapons and other tools, says Tjaark Siemssen, an archaeologist at the University of Oxford. In more modern human cultures, birch tar is used medicinally. Indigenous peoples of the Arctic incorporate it into their dressings, and the Mi’kmaq, or L’nuk, peoples of eastern Canada use birch bark extract to fight skin infections. It was found that these products kill bacteria that cause staph infections, including MRSA.
Siemssen wondered whether the tar used by Neanderthals to make tools had the same antiseptic qualities.“Applying it to wounds is something we should consider,” he says. A wise man They applied ocher to their skin, perhaps as an insecticide, Siemssen says, and researchers have long wondered whether primitive medical knowledge might have begun with other species.
Siemssen and his colleagues created the substance via a process called pyrolysis, in which a slow, controlled burn must be carried out to keep oxygen away from the accumulated tar. If oxygen enters, the bark turns to ash.
The researchers tried three strategies, each requiring an airtight compartment. One method – probably used by Neanderthals – was to burn bark under a rock and let the vapors condense into tar on its surface, then scrape it off. Modern methods use tin cans to contain the bark, which produces more tar. It’s a complicated job anyway. “Your hands are very, very dirty. It’s mostly on your skin,” says Siemssen. Each tar sample exhibited the same antibacterial properties, regardless of the production method.
If Neanderthals were smart enough to produce birch tar, Siemssen says, they might also have known about its healing power. Having such an antiseptic would have been a vital benefit to people facing the physical dangers of life in the Stone Age.
Many medicinal plants, such as yarrow and chamomilehave been discovered on Neanderthal sites, even embedded in their teeth. Birch tar might be another natural remedy they were counting on, Siemssen says. But archaeologists say it has been difficult to prove that Neanderthals knowingly practiced primitive health care.
Because the Neanderthal environment was full of other plants that could have served as antiseptics, archaeologist Karen Hardy, who studies ancient ecologies, doubts that Neanderthals used tar for medicinal purposes. “I’m not really sure whether the use of birch bark as an adhesive supports the coevolutionary use of birch bark as a medicine,” says Hardy, of the University of Glasgow in Scotland.
Whether or not birch tar was used medicinally, Siemssen says that “the world that surrounded the Neanderthals was something that they drew heavily on – medically and technologically.”
