STUDY: Neanderthals Employed Ancient Sticky Substance as Antibacterial Treatment

Relatives of modern humans might have developed and utilized a sticky material both as an adhesive and to heal their injuries, predating contemporary medicine by up to 200,000 years, according to a new study.

Scientists have long understood that Neanderthals used birch tar, a thick substance extracted from birch bark, to affix spear points to handles through a technique called hafting.

This material has been discovered throughout Europe and served multiple functions, including acting as one of history's earliest waterproof sealants and as a chewing gum-like substance.

"In addition to these discoveries, there is increasing evidence of medicinal practices and plant use among Neanderthals, which motivated our interest in birch tar's role in this regard," states Tjaark Siemssen, an archaeologist affiliated with the University of Cologne and Oxford University and the lead author of the study.

In the recent research, teams from the University of Cologne, the University of Oxford, and the University of Liège recreated birch tar using raw materials and methods that Neanderthals likely employed.

Subsequently, scientists at Cape Breton University in Nova Scotia, Canada, conducted biological experiments to verify the tar’s medicinal qualities.

"That is precisely what we demonstrated. The substance Neanderthals produced 200,000 years ago, we now know, exhibits antibacterial properties," remarks Matthias Bierenstiel, a chemistry professor at Cape Breton University and co-author of the study.

To reproduce this ancient glue-medicine, the researchers gathered bark from two species of (dead) birch trees well documented during the Late Pleistocene epoch, approximately 129,000 to 11,700 years ago.

They then applied three different tar extraction techniques to convert the bark into a sticky, spreadable substance.

The first approach involved heating birch bark inside a tin container. This method draws inspiration from the Mi'kmaq nation, the Indigenous people of Nova Scotia, who have traditionally used birch tar as a fundamental element of their herbal medicine for generations.

The other two methods simulated what Neanderthals might have done. One technique involved burning birch bark in an oxygen-deprived, sealed underground pit, producing tar through dry distillation.

The second period-appropriate method consisted of burning birch bark adjacent to a hard surface, such as a stone, then scraping off the tar that condensed on the stone’s surface.

The tar samples produced by these various methods demonstrated differing yet positive antibacterial effects against Staphylococcus aureus, a bacterium commonly linked to wound infections.

However, unsurprisingly, the tar was less effective compared to the widely used antibiotic Gentamicin. Moreover, the tar showed no impact against the notorious Escherichia coli bacterium, which typically inhabits the lower intestine.

These results imply that ancient humans employed birch tar specifically to treat wounds or skin ailments susceptible to infection.