Dichromatic Colour Vision in Wallabies as Characterised by Three Behavioural Paradigms
MetadataShow full item record
Despite lacking genetic evidence of a third cone opsin in the retina of any Australian marsupial, most species tested so far appear to be trichromatic. In the light of this, we have re-examined colour vision of the tammar wallaby which had previously been identified as a dichromat. Three different psychophysical tests, based on an operant conditioning paradigm, were used to confirm that colour perception in the wallaby can be predicted and conclusively explained by the existence of only two cone types. Firstly, colour-mixing experiments revealed a Confusion Point between the three primary colours of a LCD monitor that can be predicted by the cone excitation ratio of the short- and middle-wavelength sensitive cones. Secondly, the wavelength discrimination ability in the wallaby, when tested with monochromatic stimuli, was found to be limited to a narrow range between 440 nm and 500 nm. Lastly, an experiment designed to test the wallaby’s ability to discriminate monochromatic lights from a white light provided clear evidence for a Neutral Point around 485 nm where discrimination consistently failed. Relative colour discrimination seemed clearly preferred but it was possible to train a wallaby to perform absolute colour discriminations. The results confirm the tammar wallaby as a dichromat, and so far the only behaviourally confirmed dichromat among the Australian marsupials.
This article is published under the Open Access publishing model and distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ Please refer to the licence to obtain terms for any further reuse or distribution of this work.
Showing items related by title, author, creator and subject.
Xue, Mingliang; Liu, Wan-Quan; Li, Ling (2014)Recent research has shown improved performance by embedding the colour information in the process of facial expression recognition (FER). However, the RGB colour space may not always be the most desirable space for facial ...
Ebeling, Wiebke; Natoli, R.; Hemmi, J. (2010)Color vision in marsupials has recently emerged as a particularly interesting case among mammals. It appears that there are both dichromats and trichromats among closely related species. In contrast to primates, marsupials ...
Difficulties identifying Australian sea lions (Neophoca cinerea) in the wild using whisker spot patternsOsterrieder, Sylvia; Parnum, Iain; Salgado Kent, Chandra; Robinson, R. (2017)Individual identification is a beneficial tool in behavioural and ecological research. In mark-recapture studies, for example, it can improve abundance, residency and site fidelity estimates. Two non-invasive, ...