How did Neanderthals use birch tar?

Neanderthals may have used birch tar as an antibiotic

Experiments suggest birch tar—made from birch bark and long associated with Neanderthal toolmaking—could also have helped protect them from infection.

Researchers tested tar produced from birch bark against harmful bacteria commonly implicated in skin infections. The tar inhibited at least some bacterial growth, including Staphylococcus aureus, a major cause of infections. That matters because injuries were common in daily life, and in a world without modern antiseptics, simply having a wound-care material that reduces bacterial survival could meaningfully improve survival odds after cuts or punctures.

In the broader context of Neanderthal technology, birch tar had already been viewed as a multipurpose adhesive used to haft stone tools. This new work adds a different potential function: an antimicrobial role. In other words, the same sticky material that helped Neanderthals assemble and repair tools might also have made wounds less hospitable to microbes.

Why this finding matters

• It ties material culture to human health, not just engineering.
• It suggests Neanderthals may have understood—or at least benefited from—bioactive properties of local plants.
• It strengthens the case that ancient adhesive technologies could have had multiple functions beyond their most visible use.

Limits in the evidence

The results focus on bacterial inhibition in experiments; the reporting provides fewer details about how often and in what exact ways Neanderthals applied tar to wounds.

Even so, the study offers a plausible mechanism connecting an archaeological “tool” signature to infection control—an angle that helps explain why birch tar would be valuable enough to persist in the Neanderthal toolkit.