Meeting Abstract
148.2 Monday, Jan. 7 Nasal airway morphology and olfactory airflow in phyllostomid bats EITING, T.P.*; PEROT, J.B.; DUMONT, E.R.; UMass Amherst; UMass Amherst; UMass Amherst tpeiting@bio.umass.edu
The shape of the mammalian nasal passages plays a key role in the principal functions of the nose: respiration, olfaction, and in some bat species, echolocation. However, we still have only a rudimentary understanding of how differences in the shape of the nasal passages relate to differences in functional abilities between species. Our approach to tackling this problem has been to examine patterns of airflow among closely related species of phyllostomid bats. These species differ substantially in the relative length of the rostrum, with corresponding differences in internal airway morphology. In this study we hypothesize that these morphological differences impact the patterns of airflow to and within the olfactory region of the nose. We predict that air arrives to the olfactory region more quickly in short-faced species because of the shorter distance air travels to reach this region. We also predict that the extensive development of the olfactory recess in some species allows odorant-laden air to remain entrained for longer periods of time, potentially improving olfactory performance in these species. We used CFD to study airflow and histological preparations to examine the distribution of olfactory epithelia in three phyllostomid species. As in rodents and dogs, we found that the majority of airflow is directed ventrally through the airway, never contacting the olfactory region. Short-faced species have more extensively developed olfactory recesses, which experienced slower airflow. These short-faced species are also dedicated frugivores, so more extensive olfactory recesses may relate to these species’ reliance on olfaction in foraging. This association between the morphology of the olfactory recess and airflow is consistent with previous suggestions that the olfactory recess plays a key role in olfactory function.
