### Monday, April 20, 2015 (3:15 p.m. in Yost 306)

**Title: **The Role of Long Range Coupling in the Crayfish Swimmeret System

**Speaker:** Lucy Spardy (Postdoctoral Fellow, Mathematical Biosciences Institute, Ohio State University)

**Abstract: **The crayfish swimmeret system provides an ideal model for studying coordinated limb activity. During forward swimming, four pairs of limbs move rhythmically in a back to front metachronal wave to propel the crayfish through the water. These limbs, referred to as swimmerets, exhibit an approximate 25% phase lag between neighbors. We study the mechanism responsible for this coordinated limb behavior in a model which represents the neural circuitry as a chain of coupled oscillators. Previous modeling efforts have only considered the effects of nearest neighbor coupling, ignoring the presence of longer range connections in the system. Using both both analytical arguments and numerical simulations, we show that the long-range coupling tends to decrease phase differences between neighbors. Combined with recent fluid dynamics experiments, we suggest that this faster wave may maximize swimming efficiency.