Medical technology for palaeontology: unravelling bone diseases in fossil dwarf hippos

The Palaeontological Museum of the University of Catania houses important historical vertebrate collections, including hundreds of fossil remains belonging to the endemic Middle and Late Pleistocene dwarf hippo Hippopotamus cf. pentlandi. This material represents an extraordinary fossil record offering a unique opportunity to apply palaeopathological investigations with the aim of identifying and describing bone lesions and diseases that affected these insular hippos. Here, we offer the first CT-based description of anomalies and pathologies identified both inside and on the surface of the bones. The presence of abnormal bone tissue proliferation, microfractures and structural alterations, documented in 21 specimens of Hippopotamus cf. pentlandi from the Accordi Collection, allowed us to define the pathological course and the implications for the health conditions of the affected individuals. The study includes comparisons with pathological bones of present-day hippos, through the use of 3D models and tomographic images. This integrated approach not only deepens the understanding of pathological conditions in Hippopotamus cf. pentlandi but also provides valuable insights into the adaptations and environmental pressures these animals endured. Specifically, it sheds light on how mechanical stress, climatic factors, and ecological dynamics affected their skeletal structures. By analysing the interplay between these factors, this methodology facilitates a deeper reconstruction of the challenges faced by this extinct species within its insular habitat.