General Homeostasis of the Frequency of Circadian Oscillations

Some well-defined statistical regularities characterize the change in period (τ) of cockroach circadian oscillations subjected to a large temperature step. These are explainable in terms of the well-known temperature-compensation (homeostasis) of τ of circadian oscillations. The same regularities are detectable in published data on the effect of several other variables affecting several other circadian oscillations. The proposition is then developed that the temperature-compensation of τ is only a special case of a general homeostatic conservation of the frequency of circadian oscillations in the face of all changes they are likely to encounter in the cell. Such a general homeostasis of τ is a functional prerequisite for an oscillator to function as a useful “clock.”