Retinal Ganglion Cell Topography and Spatial Resolution in Three Indian Pteropodid Bats

We present retinal ganglion cell topographic maps and anatomical estimates of spatial resolution in three southern Indian pteropodid species with different roosting preferences. Ganglion cell densities are between 1,000 and 2,000 cells/mm2 in the central retina and lower in the dorsal and ventral periphery. All three species have a temporal area in the retina with peak ganglion cell densities of 4,600 –6,600 cells/mm2. As a result, the foliage-roostingCynopterus sphinx and the cave-roostingRousettus leschenaultii have similar anatomical resolution (2.7 and 2.8 cycles/degree, respectively). The anatomical estimate for the larger tree-roostingP. giganteus (4.0 cycles/degree) is higher than the spatial resolution determined earlier in behavioural tests. Like other pteropodids and unlike other vertebrates, all three species have choroidal papillae. Based on 15 pteropodid species studied to date, we find no relationship between roost type and eye size or visual acuity. For a general understanding of the sensory ecology of pteropodids that perform key ecosystem services in the tropics, it will be essential to study additional species.Brain Behav Evol
Source: Brain, Behavior and Evolution - Category: Neurology Source Type: research