Stone tools, or lithics, provide some of the strongest physical evidence of prehistoric culture and behaviour. In fact, chipped stone production – using a hammerstone to strike another raw material (called a core) to produce sharp flakes – dates back over 3 million years. “The entire system of stone tool production – from finding suitable raw materials to producing and using tools – is our main line of evidence about various aspects of these prehistoric lives,” explains MORPHOLITHEX Marie Skłodowska-Curie fellow Tamara Dogandžić from the MONREPOS Archaeological Research Centre and Museum for Human Behavioural Evolution, Germany. “These tools help to show how our ancestors adapted to the landscape and changing environment, and also provide an insight into knowledge transmission and skill acquisition.” Archaeologists know that flintknapping, or the production of chipped stone artefacts, is a complex motor skill. Replicative experimental work has revealed how careful manipulation of both the hammerstone and core, as well as striking angles and forces, results in different flake sizes and shapes. “Produced flakes can therefore tell us a lot about human needs and intended tasks,” says Dogandžić. “The problem is that replicative experiments also involve a certain amount of subjectivity. It is not always easy to identify the specific variables required to produce a specific flake, just by doing it.”
Tool shaping examined
The MORPHOLITHEX project, which was undertaken with the support of the Marie Skłodowska-Curie Actions programme and coordinated by the Max Planck Society, Germany, set out to better understand exactly how our ancestors made stone tools, and the techniques they applied to achieve specific sizes and shapes. This time however, the project did not rely on humans replicating the flintknapping process. Instead, the team used artefacts made in a more controlled experimental context. “The flintknapping process is so complex,” explains Dogandžić. “There are so many variables playing a role at the same time. This controlled experiment therefore helped us to really examine in detail how independent variables affect flake size and shape.” Dogandžić and her colleagues used a device containing a pneumatic cylinder with attached hammer, to simulate the flintknapping process. All the variables involved in removing a flake from a core were then captured, and the produced flakes 3D-scanned. This work was carried out at the University of Pennsylvania in Philadelphia, a partner institution in this project. “Finally, we used statistical modelling to best describe the effect of control variables, independently and in combination with others, on the size and shape of resulting flakes,” says Dogandžić.
Understanding prehistoric behaviour
In essence, the project achieved a better understanding of the flintknapping process, by using technology to capture some of the principles of stone fracture mechanics. This could help to shine a light on how people in the past understood and used the rules of flake formation to produce stone artefacts. The project team also demonstrated how controlled experiments such as this can benefit the field of archaeology. “As these are fundamental rules related to how stone fractures, the results can be applied to flaked stone technologies from any time period of prehistory,” adds Dogandžić. Finally, in addition to its results on flake formation, the project has made its 3D collection of experimental stone artefacts available to other researchers. This will enable further studies into how our ancestors shaped their stone tools, their comprehension of complex geometries, and how our facility to shape and control our world evolved.
MORPHOLITHEX, prehistoric, flint, archaeologists, hammerstone, flintknapping, prehistory