Scotopic colour vision in nocturnal hawkmoths
Author
Summary, in English
Humans are colour-blind at night, and it has been assumed that this is true of all animals. But colour vision is as useful for discriminating objects1 at night as it is during the day. Here we show, through behavioural experiments, that the nocturnal hawkmoth Deilephila elpenor uses colour vision to discriminate coloured stimuli at intensities corresponding to dim starlight (0.0001 cd m-2). It can do this even if the illumination colour changes, thereby showing colour constancya property of true colour vision systems2. In identical conditions humans are completely colour-blind. Our calculations show that the possession of three photoreceptor classes reduces the absolute sensitivity of the eye, which indicates that colour vision has a high ecological relevance in nocturnal moths. In addition, the photoreceptors of a single ommatidium absorb too few photons for reliable discrimination, indicating that spatial and/or temporal summation must occur for colour vision to be possible. Taken together, our results show that colour vision occurs at nocturnal intensities in a biologically relevant context
Department/s
Publishing year
2002
Language
English
Pages
922-925
Publication/Series
Nature
Volume
419
Issue
6910
Document type
Journal article
Publisher
Nature Publishing Group
Topic
- Zoology
Status
Published
Research group
- Lund Vision Group
ISBN/ISSN/Other
- ISSN: 0028-0836