In recent decades, advances in lighting technology have precipitated exponential increases
in night sky brightness worldwide, raising concerns in the scientific community about the …

Given the marked variation in abiotic and biotic conditions between day and night, many
species specialise their physical activity to being diurnal or nocturnal, and it was long …

Most processes within organisms, and most interactions between organisms and their
environment, have distinct time profiles. The temporal coordination of such processes is …

This Review presents a broad overview of adaptations of truly Arctic and Antarctic mammals
and birds to the challenges of polar life. The polar environment may be characterized by …

Woolly mammoths and living elephants are characterized by major phenotypic differences
that have allowed them to live in very different environments. To identify the genetic changes …

Sleep appears to be a universally conserved phenomenon among the animal kingdom, but
whether this notable evolutionary conservation underlies a basic vital function is still an …

Daily rhythms of physiology and behaviour are governed by an endogenous timekeeping
mechanism (a circadian 'clock'), with the alternation of environmental light and darkness …

Background Circadian clocks allow organisms to anticipate daily fluctuations in their
environment by driving rhythms in physiology and behavior. Inter-organismal differences in …

Circadian clocks are centrally involved in the regulation of daily behavioural and
physiological processes. These clocks are synchronized to the 24 h day by external cues …

Circadian rhythms are nearly ubiquitous throughout nature, suggesting they are critical for
survival in diverse environments. Organisms inhabiting largely arrhythmic environments …