Robust simplicity in the multimodal sensory control of insect flight.

Animal movement combines many physiological and physical systems to enable agility and robust behavior. Frequently the behavior that’s manifest can be describe, at least in specific experimental contexts, by relatively low order, and often linear, dynamical systems. How does this simplicity arise from the component systems and are the emergent dynamics preserved in the face of changes of context? Insect flight is challenging task with unstable mechanics and control requirements on the order of a single wingstroke. Using an agile hawk moth, Manduca sexta, tracking a robotic flower during foraging behavior we have shown that the underlying frequency response is linear, time invariant on the scale of 10’s of seconds, and relies on the linear superposition of vision and touch (via the moth’s long proboscis). However, as light levels drop the dynamics of the visual system adjusts, producing slower responses and reduced visual-motor gains. Does the simple emergence remain? We show that the mechanical, touch response to the flower also adjust correspondingly to produce a robust linear superposition of the two cues across contexts. In high and low light cases the two sensory system partition the frequency domain and this partition shifts as light levels dim.