Meeting Abstract
Animals must maintain maneuverability despite difference in sensory ecology. Both sensory and motor conditions vary widely both across species and within individuals. Many species of hawkmoths forage from moving, wind-blown flowers and must track flower movements to feed. Yet light intensity can vary by up to 10 billion fold over the course of the day. We compared three species of hawkmoths active in diurnal, crepuscular and nocturnal environments. Using robotic flowers that sway with repeated movements composed of the sum of many sinusoids, we have characterized the dynamics of flower tracking. The crepuscular species, Manduca sexta, slows down its neural processing to increase sensitivity in dim environments, but only to a point that it does not affect how it tracks natural flower movements. We investigated if temporal slowing in neural processing changes could predict shifts in performance to the diurnal species, Macroglossum stellatarum and the nocturnal Deilephila elpenor. Across species the nocturnal D. elpenor demonstrated the greatest phase lag and gain overshoot consistent with the slowest visual processing. All species demonstrated a luminance-dependent tracking behavior, but the effects of changing luminance were much more pronounced in the diurnal and crepuscular species. The nocturnal species tracks more poorly at higher luminance levels and may have maximized its visual sensitivity to its extreme environment even at the cost of robust maneuverability. Comparing maneuverability across species reveals how neuromechanical processing matches the sensory demands of animals’ environments.
