TY - JOUR
T1 - Behavioural evidence for colour vision in an elasmobranch
AU - Van-Eyk, Sarah M.
AU - Siebeck, Ulrike E.
AU - Champ, Connor M.
AU - Marshall, Justin
AU - Hart, Nathan S.
PY - 2011/12
Y1 - 2011/12
N2 - Little is known about the sensory abilities of elasmobranchs (sharks, skates and rays) compared with other fishes. Despite their role as apex predators in most marine and some freshwater habitats, interspecific variations in visual function are especially poorly studied. Of particular interest is whether they possess colour vision and, if so, the role(s) that colour may play in elasmobranch visual ecology. The recent discovery of three spectrally distinct cone types in three different species of ray suggests that at least some elasmobranchs have the potential for functional trichromatic colour vision. However, in order to confirm that these species possess colour vision, behavioural experiments are required. Here, we present evidence for the presence of colour vision in the giant shovelnose ray (Glaucostegus typus) through the use of a series of behavioural experiments based on visual discrimination tasks. Our results show that these rays are capable of discriminating coloured reward stimuli from other coloured (unrewarded) distracter stimuli of variable brightness with a success rate significantly different from chance. This study represents the first behavioural evidence for colour vision in any elasmobranch, using a paradigm that incorporates extensive controls for relative stimulus brightness. The ability to discriminate colours may have a strong selective advantage for animals living in an aquatic ecosystem, such as rays, as a means of filtering out surface-wave-induced flicker.
AB - Little is known about the sensory abilities of elasmobranchs (sharks, skates and rays) compared with other fishes. Despite their role as apex predators in most marine and some freshwater habitats, interspecific variations in visual function are especially poorly studied. Of particular interest is whether they possess colour vision and, if so, the role(s) that colour may play in elasmobranch visual ecology. The recent discovery of three spectrally distinct cone types in three different species of ray suggests that at least some elasmobranchs have the potential for functional trichromatic colour vision. However, in order to confirm that these species possess colour vision, behavioural experiments are required. Here, we present evidence for the presence of colour vision in the giant shovelnose ray (Glaucostegus typus) through the use of a series of behavioural experiments based on visual discrimination tasks. Our results show that these rays are capable of discriminating coloured reward stimuli from other coloured (unrewarded) distracter stimuli of variable brightness with a success rate significantly different from chance. This study represents the first behavioural evidence for colour vision in any elasmobranch, using a paradigm that incorporates extensive controls for relative stimulus brightness. The ability to discriminate colours may have a strong selective advantage for animals living in an aquatic ecosystem, such as rays, as a means of filtering out surface-wave-induced flicker.
UR - http://www.scopus.com/inward/record.url?scp=83155192234&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/arc/DP0558681
U2 - 10.1242/jeb.061853
DO - 10.1242/jeb.061853
M3 - Article
C2 - 22116761
AN - SCOPUS:83155192234
SN - 0022-0949
VL - 214
SP - 4186
EP - 4192
JO - Journal of Experimental Biology
JF - Journal of Experimental Biology
IS - 24
ER -