Analysis of Association of Ultradian Body Temperature Rhythms in Animals with Intensity of Fluctuations of Radioactive Decay of Natural K Isotope.

The study monitored the long-term body temperature (BT) oscillations of C57BL/6 mice and outbred starlings (Sturnus vulgaris) to compare them with fluctuation in decay rate of radioactive natural K isotope. The spectrum analysis revealed simultaneous changes of the predominant periods in BT spectra of the animals and those in fluctuation in K decay rate. A positive correlation was established between BT dynamics and fluctuation in decay rate. The superposed epoch analysis revealed predominant coincidence of the moments of BT and fluctuation in K decay rate. The novel data indicate association between BT ultradian rhythms with quasirhythmic variations of fluctuation in K decay rate.