Meeting Abstract
Comparative studies of fish swimming have been limited by the lack of formal, quantitative definitions of fish gaits. Swimming gaits are fluid, and defined categorically by the fin or region of the body that is used as the main propulsor (e.g. carangiform, anguilliform , balistiform, labriform). This method of categorization is limited by lack of quantitative rigor, the inability to incorporate the contributions of multiple propulsors, and the inability to compare gaits across categories. I propose an alternative framework for the definition, comparison, and categorization of fish gaits based on the propulsive contribution of each structure (body, fin) being used as a propulsor relative to a locomotor output. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait-transitions can be defined as discontinuities in the trajectory through propulsive space. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories.
