Expanding ecomorphological methods: geometric morphometric analysis of Cervidae post-crania

This study presents ecomorphological methods for reconstructing paleohabitats using three-dimensional geometric morphometric analyses of Cervidae (deer and relatives) post-cranial elements. Cervids are often the most abundant taxon in Eurasian Plio-Pleistocene sites, yet their post-cranial remains are rarely utilized in paleoecological reconstructions. Cervids are found in a wide variety of habitats, and thus their ecomorphology spans an appropriate range to serve as a proxy for paleohabitat. Four morphological features are examined in this study; the calcaneus as a whole (n = 122), the medial margin of the patellar surface of the femur (n = 133), the lateral margin of the tibial plateau (n = 136), and the plantar margin of the third phalanx (n = 62). These features were chosen because they represent various aspects of cervid locomotion important for power generation, stability, and substrate interaction. For each feature, canonical variates analyses with cross-validations were used to assess how well landmark configurations distinguish among specimens from different habitat types. Cross-validations returned correct reclassifications rates ranging from 38.9% to 66.3% in a four-habitat system, with resubstitution rates of 55.4% to 79.1% correct. Most habitat groups were found to be significantly different at p < 0.0001 using permutations tests. Variation in these ecomorphological adaptations are explored via visualizations depicting “open” and “closed” habitat types, and hypotheses are presented for cervid functional morphology.

► Methods for Cervidae ecomorphology using geometric morphometrics are established. ► Morphologies of the femur, tibia, calcaneus, and third phalanx are explored. ► Most habitat groups were found to be significantly different with permutation testing. ► Correct reclassifications ranged from 71.8% to 79.1% (resubstitution) and 42.1% to 66.3% (cross-validation). ► Visualizations of ecomorphological variation and models of cervid locomotion are provided.