Bats are nocturnal animals with functional eyes and M/L and S opsin genes in the majority of the species. These genes are prerequisite for daylight, UV and dichromatic colour vision. Several studies suggest that other non-visual lightsensitive pigments are also involved in the UV light perception in animals. Recent behavioural, molecular and immunohistochemical evidence supports that the opsin-like gene, neuropsin (OPN5), is identified in humans, mice and birds, where it serves as a G protein-coupled UV-sensitive photoreceptor. Based on its low sequence homology with other opsin groups, OPN5 is classified as an independent group. While the roles of non-visual light-sensitive pigment OPN5 in bats remain an open question, here we report that bat's neuropsin (OPN5) encoded by OPN5 gene shares 89-96% amino acid identity and similar domain organization with human and mouse OPN5. By PCR amplification, we confirm that all the mega and micro bats express the OPN5 gene in their genome. The expression of OPN5 is detectable only in the brain, eye and retina and not in the heart, kidney, liver, lungs and testis. This result suggests that OPN5 gene expression is neural specific in bats. OPN5 gene expression level is significantly higher in tree-roosting bats compared to cave-roosting bats. Since, the tree-roosting bats received slightly more sunlight every day when compared to cave-roosting bats. In captive conditions, the expression levels of OPN5 in the neural tissues are significantly lower than those of wild bats. Our preliminary results suggest that the opsin-like gene, neuropsin (OPN5) is involved in UV light perception in bats.

The short-nosed fruit bat, Cynopterus sphinx is a common plant-visiting bat that is widely distributed throughout the Indo-Malayan region. In this chapter, we discuss the dispersal patterns, mating strategy and genetic diversity in the short-nosed fruit bat C. sphinx. We used a broad-range of techniques, including mark-recapture, radio-telemetry and molecular biology analyses. Our studies uncovered unique aspects of the dispersal, mating system and genetic diversity of these bats. Both the sexes of C. sphinx were found to disperse completely from the natal harems before subadult stage and young female C. sphinx become members of a harem much earlier than their male counterparts. The nonharem males are reproductively active, gain access to harem females and sire more offspring in July–August breeding season than March–April breeding season and presumably obtain some reproductive success. Our molecular study shows that considerable genetic diversity was observed in this species from different zonal populations, possibly due to complete dispersal of juveniles of both the sexes from their natal groups and gene flow between the zones. All these studies suggest not only a predictive framework for future studies, but also the use of these data in the management and meaningful conservation of this species.