Biological Timekeeping.
نویسندگان
چکیده
The daily transition from light to darkness has significantly shaped the evolution of most living species, from unicellular organisms to mammals. Adaptation to this environmental constraint occurred through the emergence of a circadian system capable of adjusting both behavioral and physiological processes to this light-dark cycle. Superimposed upon the daily light-dark cycle is a seasonal influence that modifies the relative durations of day and night over the course of a year. Be they day-active or night-active, all organisms need a means of keeping time in a 24-hour world as well to adapt to the availability of food, and to avoid predators. In addition, they require a means of adjusting to changes in day length or transition times that may occur.
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عنوان ژورنال:
- Sleep medicine clinics
دوره 4 2 شماره
صفحات -
تاریخ انتشار 2009