On the efficiency of Palaeolithic birch tar making

Birch tar is an adhesive dating back to the European Middle Palaeolithic. Several possible production pathways have been derived from experimentation and their complexity is often used to argue for complex behaviours or cognitive capacities of Neanderthals and early Homo sapiens. Efficiency may help to evaluate the likelihood that one technique or another was used in the Palaeolithic. Based on published and new experimental data, we analyse the efficiency of four birch tar production methods in terms of resource and time consumption. We found that there are differences in efficiency between all these methods, but they are not as great as previously thought. The most complex underground technique is most efficient in terms of tar yield but even the least complex aboveground condensation method produces usable amounts of tar in relatively short time intervals. Our findings highlight that efficiency cannot be used to evaluate the likelihood that specific techniques were used in the Palaeolithic. Only direct archaeological data on the techniques used in the Palaeolithic will allow to make inferences about the behavioural complexity of birch tar production.

Automated summary

Birch tar, an ancient adhesive used in the European Middle Palaeolithic, has been studied for its production methods and efficiency. Research found that while there are differences in efficiency between different production methods, all methods are capable of producing usable amounts of tar. Efficiency alone cannot determine the likelihood of specific techniques being used in the Palaeolithic period.