High-resolution polarization vision in cephalopods
-
1
The University of Bristol, School of Biological Sciences, United Kingdom
-
2
The University of Queensland, School of Biomedical Sciences, Australia
-
3
The University of Queensland, Queensland Brain Institute, Australia
For cephalopods, which are colour blind, the polarization of light is thought to add another dimension to vision, thus providing an additional layer of image detail, comparable to adding colour to a black and white image. However, behavioural investigation has shown that octopods are only able to differentiate between electric field vectors (e-vectors) of light if the difference in angular orientation is greater than 20 degrees. This would mean that polarization vision would have limited utility in natural underwater lighting conditions where few objects show strong polarization contrast relative to the background.
We tested the ability of various cephalopods to discriminate between different angles of polarized light by presenting looming stimuli on a modified LCD computer monitor that displays in polarization instead of colour. By varying the e-vector angle of the looming stimulus relative to the background, and using evoked changes in body colouration as an indicator of detection, we were able to estimate minimum angular e-vector discrimination.
Cuttlefish were able to distinguish differences in orientation of polarized light as small as 1 degree, while squid and octopus were less sensitive (3-10 degrees). Not only does this finding in cuttlefish represent the most acute polarization discrimination measured behaviourally in any animal, it also provides a level of resolution suitable for natural visual scenes.
The advantages of such high-resolution polarization vision were investigated by analyzing naturalistic underwater scenes using computer based polarization imaging. Increasing the angular resolution in our system we discovered information not detected using normal-resolution imaging polarimetry and invisible to animals lacking fine e-vector angle discrimination. High-resolution polarization vision may provide a way of breaking intensity-based camouflage, and may also broaden communication channels in the polarization dimension for animals like cuttlefish that produce polarized body patterns.
Acknowledgements
Funding for this research came from AFOSR and ARC. S.E.T. was supported by postdoctoral fellowships from NSERC, and The University of Queensland. N.W.R. was supported by the BBSRC. We thank Wen-Sung Chung for cephalopod expertise and the staff at Moreton Bay Research Station for technical and logistic assistance.
Keywords:
Eye,
fish,
marine,
predation,
Retina,
Sensory Physiology,
underwater,
Vision
Conference:
Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012.
Presentation Type:
Poster (but consider for participant symposium and student poster award)
Topic:
Sensory: Vision
Citation:
Temple
SE,
Pignatelli
V,
Cook
T,
How
MJ,
Chiou
T,
Roberts
NW and
Marshall
J
(2012). High-resolution polarization vision in cephalopods.
Conference Abstract:
Tenth International Congress of Neuroethology.
doi: 10.3389/conf.fnbeh.2012.27.00244
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:
30 Apr 2012;
Published Online:
07 Jul 2012.
*
Correspondence:
Dr. Shelby E Temple, The University of Bristol, School of Biological Sciences, Bristol, United Kingdom, shelby.temple@bristol.ac.uk