Unexpectedly low UV-sensitivity in a bird, the budgerigar

نویسندگان

  • Johanna Chavez
  • Almut Kelber
  • Misha Vorobyev
  • Olle Lind
چکیده

Photoreceptor adaptation ensures appropriate visual responses during changing light conditions and contributes to colour constancy. We used behavioural tests to compare UV-sensitivity of budgerigars after adaptation to UV-rich and UV-poor backgrounds. In the latter case, we found lower UV-sensitivity than expected, which could be the result of photon-shot noise corrupting cone signal robustness or nonlinear background adaptation. We suggest that nonlinear adaptation may be necessary for allowing cones to discriminate UV-rich signals, such as bird plumage colours, against UV-poor natural backgrounds.

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عنوان ژورنال:

دوره 10  شماره 

صفحات  -

تاریخ انتشار 2014