Wide-field motion tuning in nocturnal hawkmoths
Author
Summary, in English
Nocturnal hawkmoths are known for impressive visually guided behaviours in dim light, such as hovering while feeding from nectar-bearing flowers. This requires tight visual feedback to estimate and counter relative motion. Discrimination of low velocities, as required for stable hovering flight, is fundamentally limited by spatial resolution, yet in the evolution of eyes for nocturnal vision, maintenance of high spatial acuity compromises absolute sensitivity. To investigate these trade-offs, we compared responses of wide-field motion-sensitive neurons in three species of hawkmoth: Manduca sexta (a crepuscular hoverer), Deilephila elpenor (a fully nocturnal hoverer) and Acherontia atropos (a fully nocturnal hawkmoth that does not hover as it feeds uniquely from honey in bees' nests). We show that despite smaller eyes, the motion pathway of D. elpenor is tuned to higher spatial frequencies and lower temporal frequencies than A. atropos, consistent with D. elpenor's need to detect low velocities for hovering. Acherontia atropos, however, presumably evolved low-light sensitivity without sacrificing temporal acuity. Manduca sexta, active at higher light levels, is tuned to the highest spatial frequencies of the three and temporal frequencies comparable with A. atropos. This yields similar tuning to low velocities as in D. elpenor, but with the advantage of shorter neural delays in processing motion.
Department/s
Publishing year
2010
Language
English
Pages
853-860
Publication/Series
Royal Society of London. Proceedings B. Biological Sciences
Volume
277
Issue
1683
Document type
Journal article
Publisher
Royal Society Publishing
Topic
- Zoology
Keywords
- intracellular electrophysiology
- hovering
- night vision
- hawkmoth
Status
Published
Research group
- Lund Vision Group
ISBN/ISSN/Other
- ISSN: 1471-2954