Mapping Archaeological Cultures and Periods with Network Cartography
Presentation held at Session 8: "Insights from reusing large prehistoric and interdisciplinary data" at the Big Historical Data Conference in Jena on 2023-11-24.
Network maps or flow maps are an established method in human geography to visualize and analyze movement or relationships between places. They show centers, peripheries and (invisible) borders of the mapped phenomena, with examples ranging from the service area of airlines to the spread of social media.
In an experimental study we applied this technique to draw an image of prehistoric culture as seen through the lens of archaeological science. Our dataset derived from the ROCEEH Out of Africa Database (ROAD) contains information from >1,300 sites with >15,000 assemblages. We constructed a network linking temporally overlapping assemblages and estimated their similarity using an index based on 32 artifact categories. As a result, we created a map of the likelihood of material cultures covering Africa and Eurasia between 3,000,000 and 20,000 years ago. This network can be subdivided into eleven cultural periods and more than 100 cultures and technocomplexes.
Firstly, our results show that the distribution of archaeological sites is heavily uneven, with dense clusters of sites in some regions and an underrepresentation of samples in other regions. This is the results of several layers of bias that obscure our view on the original ranges of cultures: e.g. the effect of taphonomic processes in various environments, the intensity of scientific research and their representation in the literature. Secondly, we observed that spatial autocorrelation, i.e. the decay of cultural similarity with distance, could not be detected in our dataset, which indicates that our sample size or categorical granularity might still be under-sampled, despite using one of the largest databases available. Thirdly, our maps illustrate how the naming of archaeological cultures and periods is influenced by conventions – and subject to change of conventions.
