1Department of Anthropology, University of Colorado, Boulder, 2Department of Mammalogy, National Museum, and Centre for Environmental Management, University of the Free State, Bloemfontein, South Africa
Saturday All day, Plaza Level
The taxonomic composition of fossil rodent assemblages from hominin sites can be used to infer paleohabitat structure. However, much of the fossil rodent material recovered is non-diagnostic or too incomplete to allow reliable taxonomic assessment, as is the case with the abundance of isolated fossil incisors that often confronts researchers. Thus, an ecomorphological, taxon-free method of investigating fossil rodent habitats would greatly augment our ability to utilize rodents for paleoenvironmental reconstruction.
Croft et al. (2011) [J Mammal 92:871-879] outline methods by which upper incisor morphology can be used to predict dietary preferences among caviomorph rodents. Using these methods, we have demonstrated that extant South African rodents can also be successfully partitioned into distinct ecomorphological categories. However, the application of these methods to the fossil record becomes more difficult because the necessary morphometric measurements require that the incisor be positioned correctly within its alveolus. Due to diagenesis and the inherent fragility of rodent crania, this positioning can rarely be determined even when the fossil incisor is still articulated with the premaxilla. To better the applicability of such ecomorphological approaches, we have been developing new measurements specific to isolated incisors and hemimandibles. Here we discuss these methods and their utility with material from Sterkfontein, Swartkrans and Gladysvale.