New research suggests that the extinction of the mighty cave bear might be due to dietary stresses that led to widespread vegetarianism among cave bear populations. This theory was presented recently at the 2016 International Conference of Vertebrate Morphology by Dr. Jacqueline Moustakas-Verho, a researcher with the Institute of Biotechnology at the University of Helsinki.
Cave bears were once one of the dominant predators across many areas of Europe and Asia. Images of cave bears are frequently found in early cave paintings, suggesting that early humans frequently interacted with these large carnivorous bears. The cave bear, however, went extinct roughly 25,000 years ago, and paleontologists are still unsure why.
Popular theories include effects of climate change, human overhunting, and even killer bear viruses. One hypothesis even suggests that the bears might have gone extinct due to a housing shortage caused by humans taking over the bears’ caves.
Moustakas-Verho’s research involved careful analysis of the teeth of both cave bear specimens and teeth from living bear species. According to her recent presentation, the cusps of teeth are a prime indicator of an animal’s diet, and comparing the teeth of many different specimens of the same species can provide insights to any stresses or changes in that species’ behavior:
The shape of the mammalian dentition, which is determined prior to eruption and modified only by wear, is strongly correlated with diet. Tooth shape can be described by the patterns of cusps that compose the crown, or chewing surface, of the tooth.
Thus, if teeth from a single species display a wide range of tooth shapes and wear patterns, it can indicate that diet is variable among that species.
The study of the cave bear teeth revealed that the cusps of the bears’ molars showed a higher level of both variation and complexity than other bear specimens. This data implies that not only were cave bears under environmental stresses and forced to look for alternative food sources, but also that some cave bears had adapted to a vegetarian diet for unknown reasons. This shift in diet, or the larger causes of this shift, could be behind the cave bear’s sudden extinction.
You know what they say…