Three-dimensional dental topography and feeding ecology in the extinct cave bear

• Published in: Biology Letters
• Main Authors: Pérez-Ramos, Alejandro, Romero, Alejandro, Rodriguez, Ernesto, Figueirido, Borja
• Other Authors: Universidad de Alicante. Departamento de Biotecnología, Grupo de Inmunología, Biología Celular y del Desarrollo
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society 2020
• Subjects: Cave bears; Dental topography; Feeding behaviour; Evolution; Biología Celular; Ursus arctos
• Online Access: http://hdl.handle.net/10045/112006; https://doi.org/10.1098/rsbl.2020.0792

The cave bear (Ursus spelaeus s.l.) was an iconic extinct bear that inhabited the Pleistocene of Eurasia. The cause of extinction of this species is unclear and to identify the actual factors, it is crucial to understand its feeding preferences. Here, we quantified the shape descriptor metrics in three-dimensional (3D) models of the upper teeth (P4–M2) of the cave bear to make inferences about its controversial feeding behaviour. We used comparative samples, including representatives of all living bear species with known diets, as a template. Our topographic analyses show that the complexity of upper tooth rows in living bears is more clearly associated with the mechanical properties of the items consumed than with the type of food. Cave bears exhibit intermediate values on topographic metrics compared with the bamboo-feeder giant panda (Ailuropoda melanoleuca) and specialists in hard mast consumption (Ursus arctos and Ursus thibetanus). The crown topography of cave bear upper teeth suggests that they could chew on tough vegetal resources of low quality with high efficiency, a characteristic that no living bear currently displays. Our results align with a climate-driven hypothesis to explain the extinction of cave bear populations during the Late Pleistocene. This study has been funded by the Spanish Ministry of Economy and Competitiveness-MEC (CGL2012-37866, CGL2015-68300P) and Junta de Andalucía (UMA18-FEDERJA-188) to B.F.