9603896 Webb The morphology of a unique connection between the swim bladder and the mechanosensory lateral line canal system in the head of tropical coral reef butterflyfishes will be described for the first time. It is hypothesized that this unique "laterophysic" connection makes the lateral line system, which is normally only sensitive to fluid movement, sensitive to fluid movement, sensitive to pressure stimuli such as sound. 3-D reconstruction of histological material will be used to describe morphological variation in the laterophysic connection in three Chaetodon spies and to compare them with butterflyfishes in two general that lack the connection to better define the structural features that characterize this sensory specialization. Anatomical specializations in a single genus that change the function of a sensory system are rare. The laterophysic connection is an excellent system in which to study the evolutionary functional morphology of a sensory specialization. Chaetodon is a well-known and ecologically important genus of coral reef fishes for which we have an expanding body of ecological and behavioral data, and a well-supported hypothesis of phylogenetic relationships. The results of this study will lead to collaborative neuroanatomical and behavioral investigations of the function of this unique sensory specialization.
