Neanderthals may have used birch tree bark extract to treat wounds

By Stephen Beech

Cavemen may have used an extract from birch tree bark to treat injuries, suggests new research.

Neanderthals probably used birch tar for several purposes - including treating wounds - thousands of years ago, say scientists.

Experiments confirmed the birch bark extract does have antibiotic properties.

Birch tar is often found at Neanderthal archaeological sites, and in some cases it is known to have been used as an adhesive to assemble tools.

But researchers have questioned whether Neanderthals had multiple uses for the substance.

For example, Indigenous communities in northern Europe and Canada use birch tar to treat wounds, and there is growing evidence that Neanderthals also employed a variety of medical practices.

An international research team led by Tjaark Siemssen, from the University of Oxford, set out to investigate the medicinal potential of birch tar.

They extracted tar from modern birch tree bark, specifically targeting species known from Neanderthal sites.

The team used multiple extraction methods, including distillation of tar in a clay pit and condensation of tar against a stone surface, both of which were available to Neanderthals.

When exposed to different strains of bacteria, all of the tar samples were found to be "effective" at hindering the growth of Staphylococcus bacteria known to cause wound infections.

The findings, published in the journal PLOS One, not only supported the effectiveness of Indigenous medicinal practices, but also reinforces the possibility that Neanderthals used birch tar to treat wounds.

Doctoral student Siemssen said: “We found that the birch tar produced by Neanderthals and early humans had antibacterial properties.

"This has important implications for how Neanderthals may have mitigated disease burden during the last Ice Ages, and adds to a growing set of evidence on healthcare in these early human communities.”

The team noted that there are other potential uses for birch tar, such as insect repellent, as well as other plants to which Neanderthals had access.

They say further exploration of the multiple potential uses of natural ingredients will enable a more thorough understanding of Neanderthal culture.

Siemssen said: “By bringing together research on indigenous pharmacology and experimental archaeology, we begin to understand the medicinal practices of our distant human ancestors and their closest cousins.

"Additionally, this study of 'palaeopharmacology' can contribute to the rediscovery of antibiotic remedies whilst we face an ever more pressing antimicrobial resistance crisis."

He added: “The messiness of birch tar production deserves a special mention.

"Every step of the production is a sensory experience in itself, and getting the tar off our hands after spending hours at the fire has been a challenge every time.”