AbstractThe widespread use of artificial light at night has transformed our environment, affecting thedaily activities of nearly all animals. The natural separation between day and night has beenseverely disrupted. The natural behaviors of organisms have been altered due to extendedlighting periods resulting from disrupted circadian regulation. This includes changes in thetiming and duration of foraging, feeding, resting, waking, migration, and reproduction.Diurnal species, whose reproductive cycles are more predictable in natural environments,have also suffered from this illuminated environment. This review highlights the role of theartificial light environment on various behavioral aspects, and hence the need to protect thenatural darkness to maintain the normalbehaviors and survival of a wide range of animals.