A new method for mapping spatial resolution in compound eyes suggests two visual streaks in fiddler crabs

Zahra Bagheri, Annie Jessop, Susumu Kato, Julian Partridge, Jeremy Shaw, Yuri Ogawa, Jan Hemmi

Research output: Contribution to journalArticle

Abstract

Visual systems play a vital role in guiding the behaviour of animals. Understanding the visual information animals are able to acquire is therefore key to understanding their visually-mediated decision making. Compound eyes, the dominant eye type in arthropods, are inherently low-resolution structures. Their ability to resolve spatial detail depends on sampling resolution (interommatidial angle) and the quality of ommatidial optics. Current techniques for estimating interommatidial angles are difficult, and generally require in vivo measurements. Here, we present a new method for estimating interommatidial angles based on the detailed analysis of 3D Micro-CT images of fixed samples. Using custom-made MATLAB software we determine the optical axes of individual ommatidia and project these axes into the three-dimensional space around the animal. The combined viewing directions of all ommatidia, estimated from geometrical optics, allow us to estimate interommatidial angles and map the animal's sampling resolution across its entire visual field. The resulting topographic representations of visual acuity match very closely the previously published data obtained from both fiddler and grapsid crabs. However, the new method provides additional detail that was not previously detectable and reveals that fiddler crabs, rather than having a single horizontal visual streak as is common in flat world inhabitants, likely have two parallel streaks located just above and below the visual horizon. A key advantage of our approach is that it can be used on appropriately preserved specimens allowing the technique to be applied to animals such as deep-sea crustaceans that are inaccessible or unsuitable for in vivo approaches.
Original languageEnglish
Article number jeb210195
JournalThe Journal of Experimental Biology
Volume223
Issue number1
DOIs
Publication statusPublished - 8 Jan 2020

Fingerprint

compound eyes
crab
crabs
spatial resolution
ommatidia
animal
optics
animals
micro-computed tomography
Animal Behavior
Aptitude
Arthropods
Visual Fields
methodology
animal behavior
sampling
Oceans and Seas
Visual Acuity
arthropods
decision making

Cite this

@article{8529b777a1d149fd89b43526b8e62ee3,
title = "A new method for mapping spatial resolution in compound eyes suggests two visual streaks in fiddler crabs",
abstract = "Visual systems play a vital role in guiding the behaviour of animals. Understanding the visual information animals are able to acquire is therefore key to understanding their visually-mediated decision making. Compound eyes, the dominant eye type in arthropods, are inherently low-resolution structures. Their ability to resolve spatial detail depends on sampling resolution (interommatidial angle) and the quality of ommatidial optics. Current techniques for estimating interommatidial angles are difficult, and generally require in vivo measurements. Here, we present a new method for estimating interommatidial angles based on the detailed analysis of 3D Micro-CT images of fixed samples. Using custom-made MATLAB software we determine the optical axes of individual ommatidia and project these axes into the three-dimensional space around the animal. The combined viewing directions of all ommatidia, estimated from geometrical optics, allow us to estimate interommatidial angles and map the animal's sampling resolution across its entire visual field. The resulting topographic representations of visual acuity match very closely the previously published data obtained from both fiddler and grapsid crabs. However, the new method provides additional detail that was not previously detectable and reveals that fiddler crabs, rather than having a single horizontal visual streak as is common in flat world inhabitants, likely have two parallel streaks located just above and below the visual horizon. A key advantage of our approach is that it can be used on appropriately preserved specimens allowing the technique to be applied to animals such as deep-sea crustaceans that are inaccessible or unsuitable for in vivo approaches.",
author = "Zahra Bagheri and Annie Jessop and Susumu Kato and Julian Partridge and Jeremy Shaw and Yuri Ogawa and Jan Hemmi",
year = "2020",
month = "1",
day = "8",
doi = "10.1242/jeb.210195",
language = "English",
volume = "223",
journal = "The Journal of Experimental Biology",
issn = "0022-0949",
publisher = "The Company of Biologists",
number = "1",

}

A new method for mapping spatial resolution in compound eyes suggests two visual streaks in fiddler crabs. / Bagheri, Zahra; Jessop, Annie; Kato, Susumu ; Partridge, Julian; Shaw, Jeremy; Ogawa, Yuri; Hemmi, Jan.

In: The Journal of Experimental Biology, Vol. 223, No. 1, jeb210195, 08.01.2020.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A new method for mapping spatial resolution in compound eyes suggests two visual streaks in fiddler crabs

AU - Bagheri, Zahra

AU - Jessop, Annie

AU - Kato, Susumu

AU - Partridge, Julian

AU - Shaw, Jeremy

AU - Ogawa, Yuri

AU - Hemmi, Jan

PY - 2020/1/8

Y1 - 2020/1/8

N2 - Visual systems play a vital role in guiding the behaviour of animals. Understanding the visual information animals are able to acquire is therefore key to understanding their visually-mediated decision making. Compound eyes, the dominant eye type in arthropods, are inherently low-resolution structures. Their ability to resolve spatial detail depends on sampling resolution (interommatidial angle) and the quality of ommatidial optics. Current techniques for estimating interommatidial angles are difficult, and generally require in vivo measurements. Here, we present a new method for estimating interommatidial angles based on the detailed analysis of 3D Micro-CT images of fixed samples. Using custom-made MATLAB software we determine the optical axes of individual ommatidia and project these axes into the three-dimensional space around the animal. The combined viewing directions of all ommatidia, estimated from geometrical optics, allow us to estimate interommatidial angles and map the animal's sampling resolution across its entire visual field. The resulting topographic representations of visual acuity match very closely the previously published data obtained from both fiddler and grapsid crabs. However, the new method provides additional detail that was not previously detectable and reveals that fiddler crabs, rather than having a single horizontal visual streak as is common in flat world inhabitants, likely have two parallel streaks located just above and below the visual horizon. A key advantage of our approach is that it can be used on appropriately preserved specimens allowing the technique to be applied to animals such as deep-sea crustaceans that are inaccessible or unsuitable for in vivo approaches.

AB - Visual systems play a vital role in guiding the behaviour of animals. Understanding the visual information animals are able to acquire is therefore key to understanding their visually-mediated decision making. Compound eyes, the dominant eye type in arthropods, are inherently low-resolution structures. Their ability to resolve spatial detail depends on sampling resolution (interommatidial angle) and the quality of ommatidial optics. Current techniques for estimating interommatidial angles are difficult, and generally require in vivo measurements. Here, we present a new method for estimating interommatidial angles based on the detailed analysis of 3D Micro-CT images of fixed samples. Using custom-made MATLAB software we determine the optical axes of individual ommatidia and project these axes into the three-dimensional space around the animal. The combined viewing directions of all ommatidia, estimated from geometrical optics, allow us to estimate interommatidial angles and map the animal's sampling resolution across its entire visual field. The resulting topographic representations of visual acuity match very closely the previously published data obtained from both fiddler and grapsid crabs. However, the new method provides additional detail that was not previously detectable and reveals that fiddler crabs, rather than having a single horizontal visual streak as is common in flat world inhabitants, likely have two parallel streaks located just above and below the visual horizon. A key advantage of our approach is that it can be used on appropriately preserved specimens allowing the technique to be applied to animals such as deep-sea crustaceans that are inaccessible or unsuitable for in vivo approaches.

UR - http://www.scopus.com/inward/record.url?scp= 85077760933&partnerID=8YFLogxK

U2 - 10.1242/jeb.210195

DO - 10.1242/jeb.210195

M3 - Article

VL - 223

JO - The Journal of Experimental Biology

JF - The Journal of Experimental Biology

SN - 0022-0949

IS - 1

M1 - jeb210195

ER -