An international research team led by scientists from the University of Cologne, Germany, and the University of Oxford, U.K., has found compelling evidence that now-extinct Neanderthals living in the Levant extracted and used birch tar for numerous purposes, including as a wound-healing agent.
The research team behind the discovery said their experiments support the efficacy of indigenous medicinal practices and add support to the idea that Neanderthals used birch tar as an antibiotic to help wounds heal, as well as a versatile material for other applications.
Neanderthals Used Birch Tar for Fastening Tools
After the last common ancestor of modern humans and Neanderthals left Africa over 200,000 years ago, the two species underwent parallel evolution, leading to their coexistence by approximately 65,000 years ago. Neanderthals disappeared from the archaeological record around 42,000 years ago, although scientists have yet to identify the full range of factors that led to their extinction.
Although early archaeological studies suggested that Neanderthals were less intelligent and less evolved than Homo sapiens, 21st-century scientists have shown that humanity’s nearest cousins may have been just as intelligent.
More recently, scientists have unearthed several stunning examples of Neanderthals burying their dead, painting, and creating tools as far back as 70,000 years ago. Some studies have found evidence of Neanderthal artwork that predates the earliest Homo sapiens works by millennia.
According to a published statement from the researchers behind the new study, archaeologists studying several ancient Neanderthal sites have found samples of birch tar. One study found that the tar was likely used as an adhesive to assemble tools. These discoveries suggested that this enigmatic, ancient species may have found other uses for this surprisingly versatile natural substance. This includes exploring the material’s healing properties, which have been exploited by indigenous communities in Northern Europe and Canada.
Exploring Birch Tar’s Possible Antibiotic Properties
Instead of studying ancient samples of birch tar found at dig sites, the researchers extracted tar from a modern birch tree. To best approximate the tar available to Neanderthals, the researchers extracted tar from a birch species discovered at proven Neanderthal sites.
Because the exact method these ancient hominins used to extract the tar has not been confirmed, the team employed several different approaches. This included extracting birch tar via distillation in a clay pit and condensing it onto a stone surface. According to the researchers, both methods would have been available to Neanderthals.
To explore the natural material’s healing potential, the team exposed samples to different strains of bacteria. As hoped, the extracted tar was “effective at hindering the growth of Staphylococcus bacteria,” which is known to cause infections in open wounds.
“We found that the birch tar produced by Neanderthals and early humans had antibacterial properties,” the researchers write. “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.”
Potential Benefits Include Insect Repellent and Antibiotic Resistance Potential
Although the team’s experiments support the use of birch tar as an antibiotic, the researchers said this versatile substance may have had many other uses that Neanderthals may have exploited. For example, birch tar can be used as an insect repellent.
The team also notes that other plants in the ancient hominin’s environment had utilitarian properties that they may have employed. However, they caution, their study also revealed that the process of extracting and manipulating the tar may have proven an impediment to Neanderthals.
“The messiness of birch tar production deserves a special mention,” they explained. “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.”
When discussing the implications of their findings, the researchers noted that understanding the tools and materials Neanderthals used and exploited offers unique insights into their society and culture, including adding yet another possible similarity between neanderthals and modern humans. The research team also highlighted the benefits of “bringing together research on indigenous pharmacology and experimental archaeology,” including understanding the medicinal practices of ancient humans and Neanderthals alike.
In the study’s conclusion, the research team also highlighted the potential benefits to modern science, including offering a potential research target for “an ever more pressing antimicrobial resistance crisis.”
The study “Antibacterial properties of experimentally produced birch tar and its medicinal affordances in the Pleistocene” was published in PLOS One.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.