Increased dietary specialization has been considered a significant predictor for risk of extinction within the fossil record, yet dietary breadth is infrequently quantified via behavioral data for extinct species. Using the fossil record of the John Day Formation, we reconstructed dietary niche breadth for the regional community of canids via morphological tooth traits and dental microwear textures to assess how measures of dietary behavior and plasticity might influence species durations. This dataset contains the list of all specimens analyzed for this project along with DMTA attribute values for each specimen, standard ellipse volumes (SEV), and general locality information. We found that signals of dietary behavior, as inferred from dietary niche breadth estimated via dental microwear textures, showed a stronger relationship with lineage durations than morphological tooth traits. Specifically, dietary niche breadth was negatively associated with increased species durations. These results suggest the relationship between overall dental morphology and dietary behaviors is more nuanced than previously expected and that the contribution of dietary flexibility irrespective of tooth morphology to extinction risk deserves further attention.

Funding provided by: American Society of MammalogistsROR ID: https://ror.org/058rchw45Award Number: Funding provided by: Society for the Study of EvolutionROR ID: https://ror.org/057kr0a20Award Number: Funding provided by: Oregon State UniversityROR ID: https://ror.org/00ysfqy60Award Number: Funding provided by: Museum of Vertebrate ZoologyROR ID: https://ror.org/01rdg4502Award Number: