It seems as though the incredibly difficult tar-based glue that Neanderthals made wasn’t so difficult to make after all. It was previously thought that the glue – which they made from birch tree bark – had to be created in oxygen-free environments in order to preserve some of the chemicals of the burnt bark. However, new studies have shown that the glue wasn’t as hard to make as was once thought.
Researchers discovered that they could just as easily create the glue in the open air and it was even stronger than if they would have made it in an oxygen-free environment. They recreated the glue by setting some birch bark on fire, and then they placed a stone next to the fire so that the flames licked the side of the rock. After about three hours of burning the bark onto the rock, they had enough tar that they could scrape off and use to glue a flint flake to a wooden handle. Then they used the tool to scrape some wood as well as take some flesh off of a calf bone and incredibly enough, the tool remained glued together throughout both activities. Pictures of their experiment can be seen here.
While their findings indicate that the glue wasn’t as hard to create as previously thought, that doesn’t mean that Neanderthals weren’t intelligent. Their study just proves that complex thoughts and planning weren’t involved with making the glue and that it was a “mere repetition of bringing two objects in close proximity and gathering of a resource,” said the researchers. They also added, “Tar production can be an accidental, and indeed even a likely, outcome of everyday activities for any group building fires with birch.”
As for how smart the researchers believe Neanderthals actually were, they wrote, “Our findings do not necessarily lead to the conclusion that Neanderthals were not able to conduct complex procedures, nor that they were not capable of abstract thinking or high planning depths.” Their cave art and burial rituals, for example, indicate that they did have a complex thought process.
Whether the glue was easy to make or a hard and complex process, just thinking about how our ancient human ancestors from hundreds of thousands of years ago lived and created things is incredible in itself. The researchers’ entire study was published in the journal Proceedings of the National Academy of Sciences and can be read here.