Dental molds from: Three-dimensional dental topography and feeding ecology in the extinct cave bear

The cave bear (Ursus spelaeus s.l.) is an iconic extinct bear that
inhabited the Pleistocene of Eurasia whose extinction causes are
controversial. To identify the actual causes of the cave bear extinction,
it is crucial to understand their feeding preferences. Here, we quantify
shape descriptor metrics (DNE, RFI and OPCR) in three dimensional (3D)
models of cave bear upper teeth (P4-M2) to make inferences on its
controversial feeding behaviour. We use a comparative sample including
representatives of all living bear species with known diets as a template.
Our topographic analyses evidence that the complexity of upper tooth rows
in living bears is more associated with the mechanical properties of the
items consumed than with the type of food. Cave bears exhibit intermediate
values on topographic metrics between those exhibited by the bamboo-feeder
giant panda (Ailuropoda melanoleuca) and those taken by specialists in
hard-mast consumption (Ursus arctos and Ursus thibetanus). The crown
topography of cave bear upper teeth suggests a high efficiency to chew on
tough vegetal resources of lower-quality, and no living bear is currently
exploiting it. Our results align with a climatic-driven hypothesis to
explain demise in cave bear populations during the late Pleistocene.