Detectors for polarized skylight in insects: A survey of ommatidial specializations in the dorsal rim area of the compound eye

Citation
T. Labhart et Ep. Meyer, Detectors for polarized skylight in insects: A survey of ommatidial specializations in the dorsal rim area of the compound eye, MICROSC RES, 47(6), 1999, pp. 368-379
Citations number
76
Categorie Soggetti
Multidisciplinary
Journal title
MICROSCOPY RESEARCH AND TECHNIQUE
ISSN journal
1059910X → ACNP
Volume
47
Issue
6
Year of publication
1999
Pages
368 - 379
Database
ISI
SICI code
1059-910X(199912)47:6<368:DFPSII>2.0.ZU;2-E
Abstract
Apart from the sun, the polarization pattern of the sky offers insects a re ference for visual compass orientation. Using behavioral experiments, it ha s been shown in a few insect species (field crickets, honey bees, desert an ts, and house flies) that the detection of the oscillation plane of polariz ed skylight is mediated exclusively by a group of specialized ommatidia sit uated at the dorsal rim of the compound eye (dorsal rim area). The dorsal r im ommatidia of these species share a number physiological properties that make them especially suitable for polarization vision: each ommatidium cont ains two sets of homochromatic, strongly polarization-sensitive photorecept ors with orthogonally-arranged analyzer orientations. The physiological spe cialization of the dorsal rim area goes along with characteristic changes i n ommatidial structure, providing actual anatomical hallmarks of polarized skylight detection, that are readily detectable in histological sections of compound eyes. The presence of anatomically specialized dorsal rim ommatid ia in many other insect species belonging to a wide range of different orde rs indicates that polarized skylight detection is a common visual function in insects. However, fine-structural disparities in the design of dorsal ri m ommatidia of different insect groups indicate that polarization vision ar ose polyphyletically in the insects. (C) 1999 Wiley-Liss, Inc.