The dual rod system of amphibians supports colour discrimination at the absolute visual threshold

Visa fullständig post



Permalänk

http://hdl.handle.net/10138/220963

Citation

Yovanovich , C A M , Koskela , S M , Nevala , N , Kondrashev , S L , Kelber , A & Donner , K 2017 , ' The dual rod system of amphibians supports colour discrimination at the absolute visual threshold ' Philosophical Transactions of the Royal Society. Biological Sciences , vol 372 , no. 1717 , 20160066 . DOI: 10.1098/rstb.2016.0066

Titel: The dual rod system of amphibians supports colour discrimination at the absolute visual threshold
Författare: Yovanovich, Carola A. M.; Koskela, Sanna M.; Nevala, Noora; Kondrashev, Sergei L.; Kelber, Almut; Donner, Kristian
Medarbetare: University of Helsinki, Ala-Laurila Lab
University of Helsinki, Department of Biosciences




Utgivare: The Royal Society of Chemistry
Datum: 2017-04-05
Språk: eng
Sidantal: 10
Tillhör serie: Philosophical Transactions of the Royal Society. Biological Sciences
ISSN: 0962-8436
DOI: http://dx.doi.org/10.1098/rstb.2016.0066
Permanenta länken (URI): http://hdl.handle.net/10138/220963
Abstrakt: The presence of two spectrally different kinds of rod photoreceptors in amphibians has been hypothesized to enable purely rod-based colour vision at very low light levels. The hypothesis has never been properly tested, so we performed three behavioural experiments at different light intensities with toads (Bufo) and frogs (Rana) to determine the thresholds for colour discrimination. The thresholds of toads were different in mate choice and prey-catching tasks, suggesting that the differential sensitivities of different spectral cone types as well as task-specific factors set limits for the use of colour in these behavioural contexts. In neither task was there any indication of rod-based colour discrimination. By contrast, frogs performing phototactic jumping were able to distinguish blue from green light down to the absolute visual threshold, where vision relies only on rod signals. The remarkable sensitivity of this mechanism comparing signals from the two spectrally different rod types approaches theoretical limits set by photon fluctuations and intrinsic noise. Together, the results indicate that different pathways are involved in processing colour cues depending on the ecological relevance of this information for each task. This article is part of the themed issue 'Vision in dim light'.
Subject: Bufo
Rana
photoreceptors
behaviour
visual threshold
colour vision
RETINAL GANGLION-CELLS
ADULT ANURAN AMPHIBIANS
FROG RANA-TEMPORARIA
TOAD BUFO-BUFO
GREEN RODS
DARK NOISE
RED RODS
PIGMENTS
VISION
LIGHT
3111 Biomedicine
1182 Biochemistry, cell and molecular biology
Licens: Paid Open Acccess.


Filer under denna titel

Totalt antal nerladdningar: Laddar...

Filer Storlek Format Granska
rstb20160066.pdf 758.4Kb PDF Granska/Öppna

Detta dokument registreras i samling:

Visa fullständig post