Hypsodonty of Dipodidae (Rodentia) in Correlation with Diet Preferences and Habitats

The evolution of molar teeth from low-crowned (brachyodont) to high-crowned (hypsodont) has traditionally been recognized as a response to increasing tooth wear due to endogenous (e.g., fiber, silica) and/ or exogenous (e.g., dust, grit) properties of ingested food. Recent work indicates that the mean hypsodonty level of large herbivorous land mammalian communities is a strong predictor of precipitation in their habitats. For small mammals, however, the research is still in an early stage. This study performed comparative studies of hypsodonty on 26 extant dipodid species with and without consideration of phylogeny. The results confirm the role of diet in shaping the cheek tooth crown height in Dipodidae. The significant relationship of investigated environmental variables with hypsodonty may be partly due to phylogenetic effects. Nonetheless, the mean hypsodonty of dipodid communities has significant relationship with regional climatic variables. Hence, the hypsodonty of dipodids also has great potential to be a regional climate proxy.