Meeting Abstract
Batoids (rays, skates, sawfishes and guitarfishes) possess a suite of sensory modalities, including vision, hearing, mechanoreception, electroreception, and olfaction. Olfaction is the longest-range sense and is crucial for initial detection of a stimulus and long-range tracking. Olfactory processes are directly tied to, or have implications for: navigation and tracking, food recognition, reproductive signaling and conspecific recognition, and predator avoidance. The anatomy (internal and external) and placement of the olfactory apparatus in batoids is highly divergent from the more recently evolved bony fish relatives (e.g. trout, tuna). Batoid species, while exhibiting considerable morphological and ecological diversity as a group, are all dorsoventrally flattened, with eyes on the opposite side of the head from their nose and mouth. They also possess an unusual nose, enlarged relative to other fishes, with numerous external flap-like structures or projections. Nasal diversity within the group is disparate, with differences in size, position, and angle of the nares, as well as the number of nasal flaps. I hypothesize that the nasal diversity displayed in this group corresponds with functional rather than phylogenetic differences. In order to quantify shape diversity, I created a morphometric model of snout and nasal differences across 15 families and 50 species. Using this model along with CT data, I propose classifications of nasal morphotypes displayed in batoids with functional and ecological implications.
