Can invertebrates see e-vector orientation as a separate modality of light?

Abstract

Event Abstract Back to Event Can invertebrates see e-vector orientation as a separate modality of light? Thomas Labhart1* 1 University of Zurich, Institute of Molecular Life Sciences, Switzerland Polarization (pol.) sensitivity is a multi-purpose visual ability including: (1) Detection of water bodies by the horizontal e-vector orientation (EVO) of reflected light by water-dependent, flying insects. Underwater, (2) the evaluation of EVO information can improve visibility and (3) EVO patterns on the bodies of some marine animals may serve visual communication. (4) The celestial compass of insects strongly relies on the celestial EVO pattern. Although all these functions exploit EVO information, the EVO of linearly polarized light is not necessarily perceived as a separate modality of light (analogous to seeing spectral lights as colors). To diagnose EVOs unequivocally, the signals of three analyzing, pol.-sensitive photoreceptors, which are tuned to different EVOs, must be compared (3D system or tripolat; Fig. 1A). A 2D system (dipolat; Fig. 1B) is unable to gauge EVOs unequivocally. A 1D system (monopolat, Fig. 1C) is totally pol.-blind since it confuses EVO and light intensity. Here, I argue that unambiguous analysis of EVOs by a 3D system is necessary for experiencing EVO as the third modality of light (called “EVO vision” further on). I also argue that 2D systems are insufficient for EVO vision due to their ambiguity. Thus, the dimensionality of pol. vision systems decides whether EVO vision is principally possible or must be excluded. So far, all but one of the pol. vision systems studied proved to be orthogonally dipolatic (Fig. 1B). The 3D system formed by the POL1 neurons of crickets is non-imaging and may be affected by the chromatic gradient in the sky. I conclude that there is no evidence so far that any organism has the potential for EVO vision in the strict sense. Some animals with 2D systems can distinguish two categories of EVOs, e.g. “Horizontal” (0°±45°) from “Vertical” (90°±45°) but are uncapable of exact EVO analysis (as 2D color vision knows just the two hues “Short” and “Long” wave). I propose that in many cases pol. sensitivity does not provide actual pol. data but grants more practical benefits, such as better underwater visibility, compass readings to traveling insects, or the alert "water underneath!" to water seeking bugs. Figure 1 Keywords: Invertebrate vision, Function of polarization sensitivity, Theory of polarization vision, Dimensionality (1-3D) of polarization vision systems, Perception of e-vector orientation Conference: International Conference on Invertebrate Vision, Fjälkinge, Sweden, 1 Aug - 8 Aug, 2013. Presentation Type: Poster presentation preferred Topic: Colour and polarisation vision Citation: Labhart T (2019). Can invertebrates see e-vector orientation as a separate modality of light?. Front. Physiol. Conference Abstract: International Conference on Invertebrate Vision. doi: 10.3389/conf.fphys.2013.25.00077 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 14 Feb 2013; Published Online: 09 Dec 2019. * Correspondence: Dr. Thomas Labhart, University of Zurich, Institute of Molecular Life Sciences, Zurich, 8057, Switzerland, thomas.labhart@imls.uzh.ch Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Thomas Labhart Google Thomas Labhart Google Scholar Thomas Labhart PubMed Thomas Labhart Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.