Seasonal breeders predominantly use photoperiod as the predictable environmental cue to time their reproduction. Terai tree frogs are long-day seasonal breeders, but the molecular mechanism is unknown. We tested the role of different photoperiodic conditions on expression levels of candidate genes involved in seasonal reproduction and epigenetic regulation.
View Article and Find Full Text PDFUrbanization is a rapidly growing phenomenon that affects wildlife. Laboratory studies show the effects of night light on the physiology of the organisms. Limited studies have been conducted on birds in their natural habitat.
View Article and Find Full Text PDFGreat efforts have been made recently to understand the effect(s) of urban environments on the circadian and seasonal physiology of wild animals, but the mechanisms involved remain largely unknown. Most laboratory studies and a few studies on animals in the wild suggest alterations occur in the physiological functions of organisms in urban habitats. Here, we addressed the effects of the interaction of seasons and urban environments on clock gene expression in three tissues of tree sparrows (Passer montanus).
View Article and Find Full Text PDFCircadian clock(s) allow an organism to be in synchrony with the surrounding environment and perform daily and seasonal physiological processes, including hibernation, migration, and reproduction. To cope with adverse environmental conditions, organisms have evolved various strategies. Insects undergo diapause, while some higher animals either migrate or hibernate/aestivate during unfavorable environmental conditions.
View Article and Find Full Text PDFSeasonality is represented as an initiation-termination-reinitiation of any physiological processes. Photoperiod is the most predictable environmental cue which organism use to time their daily physiology and seasonal functions. In natural light environmental conditions, day and night components change in terms of duration, intensity and spectrum of light available.
View Article and Find Full Text PDFAlmost all organisms live in a fluctuating environment. To achieve synchrony with the fluctuating environment, organisms have evolved with time-tracking mechanism commonly known as biological clocks. This circadian clock machinery has been identified in almost all cells of vertebrates and categorized as central and peripheral clocks.
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