Why do seals have cones? Behavioural evidence for colour-blindness in harbour seals.
(2015) In Animal Cognition 18(2). p.551-560- Abstract
- All seals and cetaceans have lost at least one of two ancestral cone classes and should therefore be colour-blind. Nevertheless, earlier studies showed that these marine mammals can discriminate colours and a colour vision mechanism has been proposed which contrasts signals from cones and rods. However, these earlier studies underestimated the brightness discrimination abilities of these animals, so that they could have discriminated colours using brightness only. Using a psychophysical discrimination experiment, we showed that a harbour seal can solve a colour discrimination task by means of brightness discrimination alone. Performing a series of experiments in which two harbour seals had to discriminate the brightness of colours, we also... (More)
- All seals and cetaceans have lost at least one of two ancestral cone classes and should therefore be colour-blind. Nevertheless, earlier studies showed that these marine mammals can discriminate colours and a colour vision mechanism has been proposed which contrasts signals from cones and rods. However, these earlier studies underestimated the brightness discrimination abilities of these animals, so that they could have discriminated colours using brightness only. Using a psychophysical discrimination experiment, we showed that a harbour seal can solve a colour discrimination task by means of brightness discrimination alone. Performing a series of experiments in which two harbour seals had to discriminate the brightness of colours, we also found strong evidence for purely scotopic (rod-based) vision at light levels that lead to mesopic (rod-cone-based) vision in other mammals. This finding speaks against rod-cone-based colour vision in harbour seals. To test for colour-blindness, we used a cognitive approach involving a harbour seal trained to use a concept of same and different. We tested this seal with pairs of isoluminant stimuli that were either same or different in colour. If the seal had perceived colour, it would have responded to colour differences between stimuli. However, the seal responded with "same", providing strong evidence for colour-blindness. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4913232
- author
- Scholtyssek, Christine LU ; Kelber, Almut LU and Dehnhardt, Guido
- organization
- publishing date
- 2015
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Animal Cognition
- volume
- 18
- issue
- 2
- pages
- 551 - 560
- publisher
- Springer
- external identifiers
-
- pmid:25452008
- wos:000349626900014
- scopus:84925541348
- pmid:25452008
- ISSN
- 1435-9456
- DOI
- 10.1007/s10071-014-0823-3
- language
- English
- LU publication?
- yes
- id
- d7125f3c-d4d3-4a1e-8de9-8d5fa34f42da (old id 4913232)
- date added to LUP
- 2016-04-01 11:05:01
- date last changed
- 2024-05-06 04:24:09
@article{d7125f3c-d4d3-4a1e-8de9-8d5fa34f42da,
abstract = {{All seals and cetaceans have lost at least one of two ancestral cone classes and should therefore be colour-blind. Nevertheless, earlier studies showed that these marine mammals can discriminate colours and a colour vision mechanism has been proposed which contrasts signals from cones and rods. However, these earlier studies underestimated the brightness discrimination abilities of these animals, so that they could have discriminated colours using brightness only. Using a psychophysical discrimination experiment, we showed that a harbour seal can solve a colour discrimination task by means of brightness discrimination alone. Performing a series of experiments in which two harbour seals had to discriminate the brightness of colours, we also found strong evidence for purely scotopic (rod-based) vision at light levels that lead to mesopic (rod-cone-based) vision in other mammals. This finding speaks against rod-cone-based colour vision in harbour seals. To test for colour-blindness, we used a cognitive approach involving a harbour seal trained to use a concept of same and different. We tested this seal with pairs of isoluminant stimuli that were either same or different in colour. If the seal had perceived colour, it would have responded to colour differences between stimuli. However, the seal responded with "same", providing strong evidence for colour-blindness.}},
author = {{Scholtyssek, Christine and Kelber, Almut and Dehnhardt, Guido}},
issn = {{1435-9456}},
language = {{eng}},
number = {{2}},
pages = {{551--560}},
publisher = {{Springer}},
series = {{Animal Cognition}},
title = {{Why do seals have cones? Behavioural evidence for colour-blindness in harbour seals.}},
url = {{http://dx.doi.org/10.1007/s10071-014-0823-3}},
doi = {{10.1007/s10071-014-0823-3}},
volume = {{18}},
year = {{2015}},
}