Arctic reindeer extend their visual range into the ultraviolet.
Level 5 - mechanism / opinion, no new human data
Non-human animal physiological and molecular laboratory study (Level 5 by design analogy).
PubMed 21613517 · doi:10.1242/jeb.053553
What was done
Evaluated UV transmission of the cornea and lens, measured electrophysiological responses of retinal rod and cone photoreceptors under low-intensity stimulation, and performed retinal RNA extraction with in vitro opsin expression in Arctic reindeer.
What was found
The reindeer cornea and lens transmit UV light, and both rod and cone photoreceptors exhibit electrophysiological responses to UV wavelengths under low-intensity stimulation. In vitro opsin expression and RNA extraction showed that this UV sensitivity is not mediated by a dedicated UV-specific opsin mechanism. The abstract reports no specific numerical data, transmission percentages, or sample sizes.
Why it matters
Reveals that large Arctic mammals can extend visual sensitivity into the ultraviolet range to utilize contrast in UV-reflective snow and vegetation, despite UV light typically causing retinal damage in other mammals.
Limits
The abstract provides no sample size, exact wavelength thresholds, or quantitative measurements of optical transmission. Protective adaptations preventing UV-induced retinal degeneration were not directly measured or demonstrated.
Cited by
- supports Reindeer are able to see ultraviolet (UV) light.