Opponent processing in the retinal mosaic of nymphalid butterflies
Abstract
The eyes of nymphalid butterflies, investigated with incident illumination, show colourful facet reflection patterns—the eye shine—which is uniform or heterogeneous, dependent on the species. Facet colours suggest that the ommatidia contain different sets of photoreceptors and screening pigments, but how the colours and the cell characteristics are associated has not been clearly established. Here, we analyse the retinae of two nymphalids, Apatura ilia , which has a uniform eyeshine, and Charaxes jasius, a species with a heterogeneous eye shine, using single-cell recordings, spectroscopy and optical pupillometry. Apatura has UV-, blue- and green-sensitive photoreceptors, allocated into three ommatidial types. The UV- and blue-sensitive cells are long visual fibres (LVFs), receiving opponent input from the green-sensitive short visual fibres (SVFs). Charaxes has an expanded set of photoreceptors, allocated into three additional, red-reflecting ommatidial types. All red ommatidia contain green-sensitive LVFs, receiving opponent input from red receptors. In both species, the SVFs do not receive any opponent input. The simple retina of Apatura with three ommatidial types and two colour-opponent channels can support trichromatic vision. Charaxes has six ommatidial types and three colour-opponent channels. Its expanded receptor set can support tetrachromatic vision.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 05, 2022
- Source ID
- 10.1098/rstb.2021.0275
Entities
People
- Andrej Meglič
- Gregor Belušič
- Marko Ilić
- Primož Pirih
Organizations
- Air Force Office of Scientific Research
- Ljubljana University Medical Centre
- Ministry of Education Science and Sport
- Slovenian Research and Innovation Agency
- University of Ljubljana