Circadian Rhythms

  • James L. Hargrove
Part of the Modeling Dynamic Systems book series (MDS)


There is nothing so commonplace as a day, or so extraordinary, for the period of time that we customarily divide into 24 hours depends upon the amount of time required for our particular planet to spin one full turn upon its axis. Move to the moon, Mars, or Jupiter, and the day takes on quite different dimensions (if by a “day” we mean one complete cycle of light and darkness). If the earth rotated slower, the day would be longer; if it did not rotate at all, we would either be bathed in perpetual sunlight, or immersed in constant darkness. Needless to say, if absolute time exists, it has nothing to do with day length!


Daily Rhythm Constant Darkness Pineal Organ Generic Oscillator Circannual Rhythm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • James L. Hargrove
    • 1
  1. 1.Department of Foods and NutritionUniversity of GeorgiaAthensUSA

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