... the retinal ganglion cell density and photoreceptor dimensions, we determined that Leach's storm petrels have six times lower spatial resolution than the northern fulmars. However, the optical sensitivity of rod photoreceptors is similar between species. These results suggest that under similar atmospheric...

... sensitivities of single photoreceptors using morphological methods. Bourke's parrots lose colour vision in brighter light (0.4 cd m –2 ) than budgerigars (0.1 cd m –2 ) and both birds lose colour vision in brighter light(`end of civil twilight') than humans (0.02 cd m –2 ,`moonlight'). The optical sensitivities...