Pleistocene brown bears from Portugal: Morphometric trends, paleoenvironmental drivers and paleobiological inferences
Autores:
Darío ESTRAVIZ-LÓPEZ
Ana GARCÍA-VÁZQUEZ
María RÍOS
Aurora GRANDAL-D’ANGLADE
Resumen:
This study analyzes over 500 brown bear remains from six Portuguese Late Pleistocene sites (Furninha, Fontainhas, Serra de Molianos, Caldeir˜ao, Escoural, and Oliveira) to provide a framework for the evolution of Ursus arctos in Western Iberia, confirming the absence of U. spelaeus and U. thibetanus so far. Furninha Cave (MIS 5, ~80,000 years ago) yielded over 400 measurable remains, including some exceptionally large and robust individuals exceeding 300 kg. Their robustness (large mediolateral diameters of long bones) and cave bear-like traits (such as long molars and thick metapodials) suggest potential ecological niche convergence, a hypothesis requiring further testing through molecular paleontology. Taphonomic alterations like gnawing marks, and pathologies, were also documented. Remains from Oliveira and possibly Escoural may belong to this robust MIS 5 population. Later bears (MIS 2, ~30,000 years ago) from Caldeir˜ao, Fontainhas, and probably Serra de Molianos were slenderer, yet some individuals may have reached ~385 kg, being among the largest U. arctos in the fossil record. On average, these bears (~250 kg) were likely comparable to contemporaneous Pleistocene populations in northwestern Spain. While Early Holocene males averaged 260 kg and females 140 kg, modern Iberian bears show significantly reduced size and sexual dimorphism (males ~140 kg, females ~100 kg). This decline likely reflects human pressures. This research provides insights into Western Iberian bear evolution and establishes a framework and hypotheses for future works, emphasizing the necessity of molecular (isotopes, aDNA), paleopathological, and taphonomic analyses to better understand these animals at both Iberian and European levels.
Palaeogeography, Palaeoclimatology, Palaeoecology 698 (2026), art. 113964. https://doi.org/10.1016/j.palaeo.2026.113964
Palabras clave: Ursus arctos, Holocene, Iberian Peninsula, Furninha Cave, Body mass, Bone measurements