  An organism's ability to move freely is a fundamental behaviour in the animal
kingdom. To understand animal locomotion requires a characterisation of the
material properties, as well as the biomechanics and physiology. We present a
biomechanical model of C. elegans locomotion together with a novel finite
element method. We formulate our model as a nonlinear initial-boundary value
problem which allows the study of the dynamics of arbitrary body shapes,
undulation gaits and the link between the animal's material properties and its
performance across a range of environments. Our model replicates behaviours
across a wide range of environments. It makes strong predictions on the viable
range of the worm's Young's modulus and suggests that animals can control speed
via the known mechanism of gait modulation that is observed across different
media.
