A specialized dorsal rim area for polarized light detection in the compound eye of the scarab beetle Pachysoma striatum.

Summary, in English

Many animals have been shown to use the pattern of polarized light in the sky as an optical compass. Specialised photoreceptors are used to analyse this pattern. We here present evidence for an eye design suitable for polarized skylight navigation in the flightless desert scarab Pachysoma striatum. Morphological and electrophysiological studies show that an extensive part of the dorsal eye is equivalent to the dorsal rim area used for polarized light navigation in other insects. A polarization-sensitivity of 12.8 (average) can be recorded from cells sensitive to the ultraviolet spectrum of light. Features commonly known to increase the visual fields of polarization-sensitive photoreceptors, or to decrease their spatial resolution, are not found in the eye of this beetle. We argue that in this insect an optically unspecialised area for polarized light detection allows it not be used exclusively for polarized light navigation.

• Author: Marie Dacke; P Nordström; C H Scholtz; Eric Warrant
• Department/s: Functional zoology; Lund Vision Group
• Publishing year: 2002
• Language: English
• Pages: 211-216
• Publication/Series: Journal of Comparative Physiology A
• Volume: 188
• Issue: 3
• Links: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11976889&dopt=Abstract; http://dx.doi.org/10.1007/s00359-002-0295-9
• Document type: Journal article
• Publisher: Springer
• Topic: Zoology
• Keywords: Scanning; Electron; Microscopy; Contrast Sensitivity : physiology; Beetles : ultrastructure; Eye : anatomy & histology; Beetles : physiology; Animal; Eye : ultrastructure; Female; Male; Light; Photic Stimulation : methods
• Status: Published
• Research group: Lund Vision Group
• ISBN/ISSN/Other: ISSN: 1432-1351