GEOGRAPHIC VARIATION IN CARNIVORAN DENTITION IN RELATION TO ENVIRONMENT

Functional traits of organisms reflect the environmental conditions they inhabit. Ecometric approaches are commonly used to relate functional traits at a community scale to environmental parameters like temperature and precipitation. Previous ecometric studies have been conducted on dentition of ungulates and glires (rodents and lagomorphs), as well as studies correlating environmental parameters and carnassial blade length of carnivorans. However, other dental characteristics of carnivoran guilds and how they reflect their environments have not been as well studied. Measurements were gathered from both the upper and lower dentition of 45 species of extant carnivorans and used to calculate a series of functional indices regularly used to study carnivoran guilds (e.g., relative carnassial blade length, relative grinding areas, etc.). We computed mean values for carnivorans from 16 communities across North America, and then compared community means across latitudes and climate conditions. The preliminary results show greater grinding area and jaw strength at lower latitudes and within wetter climates reflecting greater proportion of omnivorous and frugivorous species, while relatively more bladelike carnassials were observed at higher latitudes in colder climates reflecting a greater proportion of hypercarnivorous species and the absence of frugivores. Application of these methods has the potential to yield new information about how carnivoran guilds reflect their environments, facilitate estimation and interpretation of past environmental conditions based on fossil carnivorans, and inform understanding of how carnivoran guilds may change in the face of ongoing climate change.