Neanderthal glue

Paul Kozowyk and Geeske Langejans of Leiden University have demonstrated that there are at least three different ways to extract tar from birch bark and suggest that Neanderthals may have exploited one of the processes to make the first glue some 200,000 years ago. The discovery offers an explanation for the fact that Neanderthal spears most commonly comprise two parts, a piece of sharpened flint for the point, and a stick for the shaft. What held them together has remained an archeological puzzle for many years. A simple method to make glue involving a roll of birch bark and an open fire could solve the problem, according to the team.