Diversity of photoreceptor arrangements in nocturnal, cathemeral and diurnal Malagasy lemurs.

摘要: The lemurs of Madagascar (Primates: Lemuriformes) are a monophyletic group that has lived in isolation from other primates for about 50 million years. Lemurs have diversified into species with diverse daily activity patterns and correspondingly different visual adaptations. We assessed the arrangements retinal cone rod photoreceptors six nocturnal, three cathemeral two diurnal lemur quantified parameters species. analysis revealed lower densities higher nocturnal than photoreceptor Propithecus verreauxi indicate less "diurnal" retina found primates. Immunolabeling opsins showed presence both middle-to-longwave sensitive (M/L) shortwave (S) cones most species, indicating at least dichromatic color vision. S were absent Allocebus trichotis Cheirogaleus medius, monochromacy. In Microcebus had an inverse topography very low central highest peripheral retina. M/L all conventional peak area. With exception Eulemur eyes studied taxa, including Propithecus, possessed tapetum lucidum, feature only among crepuscular mammals.