Abstract
Vision, an important sensory modality of many animals, exhibits plasticity in that it adapts to environmental conditions to maintain its sensory efficiency. Nuptial coloration is used to attract mates and hence should be tightly coupled to vision. In Taiwan, two closely related bitterlings (Paratanakia himantegus himantegus and Paratanakia himantegus chii) with different male nuptial colorations reside in different habitats. We compared the visual spectral sensitivities of these subspecies with the ambient light spectra of their habitats to determine whether their visual abilities correspond with photic parameters and correlate with nuptial colorations. Theelectroretinogram (ERG) results revealed that the relative spectral sensitivity of P.h. himantegus was higher at 670 nm, but lower at 370 nm, than the sensitivity of P. h. chii. Both bitterlings could perceive and reflect UV light, but the UV reflection patterns differed between genders. Furthermore, the relative irradiance intensity of the light spectra in the habitat of P. h. himantegus was higher at long wavelengths (480-700 nm), but lower at short wavelengths (350-450 nm), than the light spectra in the habitats of P. h.chii. Two phylogenetically closely related bitterlings, P. h. himantegus and P. h. chii, dwell in different waters and exhibit different nuptial colorations and spectral sensitivities, which may be the results of speciation by sensory drive. Sensory ability and signal diversity accommodating photic environment may promote diversity of bitterling fishes. UV light was demonstrated to be a possible component of bitterling visual communication. The UV cue may assist bitterlings in genderidentification.
Highlights
Vision, an important sensory modality of many animals, exhibits plasticity in that it adapts to environmental conditions to maintain its sensory efficiency
The relative visual spectra of these two Paratanakia subspecies measured with ERG recording is shown in Fig. 2, which showed that bitterlings of both subspecies are able to detect light within a range of 370 nm to 670 nm under dark adaptation conditions
To obtain relative spectral sensitivity values, the sensitivity of P. h. himantegus was normalized to the stimulation intensity of the threshold at 440 nm, and the sensitivity of P. h. chii was normalized to the stimulation intensity of the threshold at 460 nm
Summary
An important sensory modality of many animals, exhibits plasticity in that it adapts to environmental conditions to maintain its sensory efficiency. We compared the visual spectral sensitivities of these subspecies with the ambient light spectra of their habitats to determine whether their visual abilities correspond with photic parameters and correlate with nuptial colorations. From those inhabiting shallow and clear waters to those in the aphotic zone in the deep ocean, can perceive visual signals (Pitcher 1986) in order to communicate, find mates, forage for food, Light spectra in aquatic environments are distinct from those on land. Since the underwater photic environments may be affected by depth and suspended materials as well as unique features of the habitats, fish under different photic conditions should physiologically adjust its spectral sensitivity in order to enhance detection ability by maximizing the visual contrast In addition to their link with visual properties, photic environments may influence overall body coloration of fish
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
