Meeting Abstract
P2.46 Saturday, Jan. 5 Cribriform plate morphology as proxy for olfactory innervation in felids and canids BIRD, DJ*; DAVYDOV, Y*; AMIRKHANIAN, A*; VAN VALKENBURGH, B; Univ. of California Los Angeles; Univ. of California Los Angeles; Univ. of California Los Angeles ; Univ. of California Los Angeles dbirdseed@gmail.com
In general, carnivorans are considered to possess a keen sense of smell. The two most studied groups of the carnivorans, the felids and canids, differ in their relative reliance on olfaction versus vision in foraging. Canids tend to rely more on olfaction and possess relatively large olfactory bulbs, while felids are considered more visual predators and have smaller olfactory bulbs. Using computed tomography scans and 3-D imaging software, this study examines one feature of the mammalian olfactory apparatus, the cribriform plate, to ask whether olfactory innervation is smaller in felids than canids. The cribriform plate (CP) is a bony cup that separates the nasal chamber from the brain case and houses the olfactory bulb. The CP is perforated with foramina that surround the olfactory nerve fibers traveling from snout to brain. CP morphology varies across mammalian species and likely reflects aspects of olfactory function. Specifically, the size and number of CP foramina vary, and cumulative foramina area may be viewed as a proxy for relative olfactory innervation. Novel spline technology has made it possible to quantify the total cross-sectional area of CP foramina for the first time and to compare this metric across species. Preliminary results reveal that the total area of cribriform plate foramina, and thus olfactory innervation, is smaller in felids than in canids. These results suggest there may be a trade-off between the enhanced visual anatomy (large, frontally directed orbits and high binocularity) and olfactory innervation among felids. In the future, these methods will be applied to fossils, in which the CP with its osseous imprints of olfactory innervation may hold promising clues to the olfactory ecology of extinct felid and canid species.
