Multifocal optical systems and pupil dynamics in birds.
(2008) In Journal of Experimental Biology 211(Pt 17). p.2752-2758- Abstract
- In animal eyes of the camera type longitudinal chromatic aberration causes defocus that is particularly severe in species with short depth of focus. In a variety of vertebrates, multifocal optical systems compensate for longitudinal chromatic aberration by concentric zones of different refractive powers. Since a constricting circular pupil blocks peripheral zones, eyes with multifocal optical systems often have slit pupils that allow light to pass through all zones, irrespective of the state of pupil constriction. Birds have circular pupils and were therefore assumed to have monofocal optical systems. We examined the eyes of 45 species (12 orders) of bird using videorefractometry, and the results are surprising: 29 species (10 orders) have... (More)
- In animal eyes of the camera type longitudinal chromatic aberration causes defocus that is particularly severe in species with short depth of focus. In a variety of vertebrates, multifocal optical systems compensate for longitudinal chromatic aberration by concentric zones of different refractive powers. Since a constricting circular pupil blocks peripheral zones, eyes with multifocal optical systems often have slit pupils that allow light to pass through all zones, irrespective of the state of pupil constriction. Birds have circular pupils and were therefore assumed to have monofocal optical systems. We examined the eyes of 45 species (12 orders) of bird using videorefractometry, and the results are surprising: 29 species (10 orders) have multifocal systems, and only five species (five orders) have monofocal systems. The results from 11 species (four orders) are inconclusive. We propose that pupils ;switching' between being fully opened (multifocal principle) to maximally closed (pinhole principle) can make multifocal optical systems useful for animals with circular pupils. Previous results indicate that mice have both multifocal optical systems and switching pupils. Our results suggest that parrots may use a similar mechanism. By contrast, owl pupils responded weakly to changes in illumination and stayed remarkably wide even in full daylight. Moreover, the parrots opened their pupils at higher light levels than owls, which correlates with the differences in sensitivity between diurnal and nocturnal eyes. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1222960
- author
- Lind, Olle LU ; Kelber, Almut LU and Kröger, Ronald LU
- organization
- publishing date
- 2008
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Experimental Biology
- volume
- 211
- issue
- Pt 17
- pages
- 2752 - 2758
- publisher
- The Company of Biologists Ltd
- external identifiers
-
- wos:000258665700012
- pmid:18723531
- scopus:53949094557
- pmid:18723531
- ISSN
- 1477-9145
- DOI
- 10.1242/jeb.018630
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Department of Clinical Sciences, Lund (013230000), Functional Zoology (432112239), Department of Cell and Organism Biology (Closed 2011.) (011002100)
- id
- 9bc8d1d4-50a7-438c-9263-3b9b97d30a76 (old id 1222960)
- alternative location
- http://www.ncbi.nlm.nih.gov/pubmed/18723531?dopt=Abstract
- date added to LUP
- 2016-04-01 11:49:51
- date last changed
- 2024-01-07 22:09:50
@article{9bc8d1d4-50a7-438c-9263-3b9b97d30a76,
abstract = {{In animal eyes of the camera type longitudinal chromatic aberration causes defocus that is particularly severe in species with short depth of focus. In a variety of vertebrates, multifocal optical systems compensate for longitudinal chromatic aberration by concentric zones of different refractive powers. Since a constricting circular pupil blocks peripheral zones, eyes with multifocal optical systems often have slit pupils that allow light to pass through all zones, irrespective of the state of pupil constriction. Birds have circular pupils and were therefore assumed to have monofocal optical systems. We examined the eyes of 45 species (12 orders) of bird using videorefractometry, and the results are surprising: 29 species (10 orders) have multifocal systems, and only five species (five orders) have monofocal systems. The results from 11 species (four orders) are inconclusive. We propose that pupils ;switching' between being fully opened (multifocal principle) to maximally closed (pinhole principle) can make multifocal optical systems useful for animals with circular pupils. Previous results indicate that mice have both multifocal optical systems and switching pupils. Our results suggest that parrots may use a similar mechanism. By contrast, owl pupils responded weakly to changes in illumination and stayed remarkably wide even in full daylight. Moreover, the parrots opened their pupils at higher light levels than owls, which correlates with the differences in sensitivity between diurnal and nocturnal eyes.}},
author = {{Lind, Olle and Kelber, Almut and Kröger, Ronald}},
issn = {{1477-9145}},
language = {{eng}},
number = {{Pt 17}},
pages = {{2752--2758}},
publisher = {{The Company of Biologists Ltd}},
series = {{Journal of Experimental Biology}},
title = {{Multifocal optical systems and pupil dynamics in birds.}},
url = {{http://dx.doi.org/10.1242/jeb.018630}},
doi = {{10.1242/jeb.018630}},
volume = {{211}},
year = {{2008}},
}