Meeting Abstract
Animals evolved nervous systems that can detect specific physical features of their environment. Localization of sound in space is important in vertebrates, who use the information for communication and predator detection, and thus they have evolved nuclei in the auditory brainstem that encode cues for localization well. The circuitry and connections of these nuclei have been well studied in mammals and birds. Crocodilians are a particularly interesting group to study because they have not changed morphologically in millions of years, and are a sister group to birds. Further, crocodilians, including the Alligator mississippiensis, live in acoustically challenging environments and have well developed vocalization repertoires. This project examines the projections of the auditory nerve to the primary auditory brainstem nuclei. We used anatomical techniques including immunohistochemistry and neuronal tract tracing to map out the pathway of the auditory nerve. Since these nuclei have been shown to be present in all archosaurs, results provide insights into the evolution of sound localization. Any differences or similarities in connectivity will shed light on the ancestral condition of the group.
