(162c) Gait Adaptation Of Swimming C. Elegans: Hydrodynamic Efficiency and Neuromuscular Control

A millimeter-size nematode Caenorhabditis elegans is one of the most
important model organisms used for investigations ranging from genetics to
neurobiology.  Applications such as mutant or drug screening require a
thorough understanding of nematode locomotion in complex environments to
quantify the interplay of sensing processes, control mechanisms, and
mechanical interactions (including frictional, capillary, and hydrodynamic
forces).  Our analysis of nematodes swimming in fluids of different
viscosities shows that the worms choose the optimal gait that minimizes
the combined energy dissipation resulting from hydrodynamic and internal
friction forces.  Simple models of neuromuscular control of the nematode
body will be presented to further elucidate the observed gradual change of
the wavelength and frequency of nematode undulations when fluid viscosity
is increased.