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The visual perception of birds is an incredibly exciting subject of research. Birds have significantly higher visual acuity than most other animals, which helps them stay safe in flight and detect their prey. Understanding how the eyes send information to the brain for additional processing is crucial. The brain has sections (nuclei) that accept input from the retina. The key areas where information is processed are the hyperpallium apicale (HA), hippocampus (HP), optic tectum (TeO), nucleus rotundus (RoT), and the geniculatus lateralis ventralis (Glv); among these, the RoT is one of the most investigated nuclei for vision. This study looked at how the visual centers of non-photoperiodic songbirds (Spotted Munia) adapt in different life history stages by looking at NPY expression. We immunohistochemically quantified NPY expression in four different seasons, including pre-breeding (June), breeding (September), post-breeding (December), and regressed (March) in the brain of Spotted Munia. We evaluated changes in the expression levels of the peptide throughout the year, by determining the expression at four different periods throughout the year. Peptide expression levels were projected to fluctuate within photoperiod-induced seasons. It was discovered that the parts of the brain related to vision (RoT, HA, and HP) have a higher number of immunoreactive cells during their mating season, i.e., during the summer. The appearance of NPY, a non-photic marker, in brain areas linked with light perception, was fascinating. Indirectly, NPY aids avian reproduction in a variety of ways. These findings demonstrate the importance of these nuclei in the process of reproduction, as well as the involvement of NPY in the visual brain areas of Spotted Munia.

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Light, the most abundant and important stimuli, can be sensed by a single photon by the photoreceptors. These photoreceptors are usually a group of protein of GPCR (G protein-coupled receptor) family. Opsins, a group of this family absorb these photons and processes both image forming and non-image forming phototransduction. Initially, their role was only limited to image formation, but recent studies reveal their importance in non -image forming functions also. In this review, we discussed various roles of opsins other than image formation, such as in photorelaxation of blood vessels, mechanoreception of skin, temperature regulation, hearing, immune system, thermotaxis of sperms, photosensation as well as in reproduction. These various functions of opsins show their immense importance in non-image forming functions as well as their evolutionary importance.

Migratory songbirds fly over long distances to avoid adverse conditions at their breeding and wintering grounds, and this phenomenon is known as ‘migration’. This migratory phenomenon is highly energy demanding. The present study was aimed to analyze the morphometric analysis of body mass, beak, wings, tail, and tarsus length of two migratory finches i.e., red-headed (RHB) and black-headed buntings (BHB) to investigate whether they showed differences in their morphological attributes. This observational study shows an understanding of the characterization of wing patterns and differences in the length of tarsus, tail, beak, and wings of both species. The size of the beak, tail, and wings of BHB is significantly different when compared to RHB. In addition, body mass was significantly high in BHB than that of RHB during their spring migration (preparatory phase). T