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Forgotten books: The application of unseen species models to the survival of culture

The study of ancient cultures is hindered by the incomplete survival of material artifacts, so we commonly underestimate the diversity of cultural production in historic societies. To correct this survivorship bias, we applied unseen species models from ecology to gauge the loss of narratives from medieval Europe, such as the romances about King Arthur. The estimates obtained are compatible with the scant historic evidence. In addition to events such as library fires, we identified the original evenness of cultural populations as an overlooked factor in these assemblages’ stability in the face of immaterial loss. We link the elevated evenness in island literatures to analogous accounts of ecological and cultural diversity in insular communities. These analyses call for a wider application of these methods across the heritage sciences. Description Ecological methods for cultural history Much of the narrative literature from the European Middle Ages has been lost over the ages because of manuscript physical degradation and destruction, including library fires. Kestemont et al. show that established methods from ecology for estimating the numbers of unseen species can be applied to abundance data representing cultural artifacts to estimate the losses that ancient cultural domains have sustained over the centuries. The authors obtain estimates that not only corroborate existing hypotheses from book history, but also reveal unexpected geographic differences that have gone unnoticed so far. For example, insular literatures, such as those from Iceland and Ireland, combine a surprisingly strong cultural persistence with an elevated distributional evenness. —AMS Quantitative ecological methods can be used to estimate the extent of losses of medieval narrative literature.