TEMPORAL ASSOCIATIONS OF LIFE WITH SOLAR AND GEOPHYSICAL ACTIVITY

In biology, circadian rhythms with a period of one cycle in 20-28 h ar e known to be ubiquitous and partly endogenous. Rhythms with a frequen cy lower than one cycle per day are called 'infradian rhythms'. Among them are components with one cycle in about 3.5, 7, 14 and 28 days, th e multiseptans, which, like the circadians, must be regarded as a gene ral characteristic of life: they characterize unicells as well as much more differentiated organisms. We hypothesize that heliogeophysical f actors other than the solar visible light, held responsible for the ev olution of circadian periodicity, underlie the infradian rhythms of bi osystems. The periodicities in the solar wind and variations in the in terplanetary magnetic field (IMF) which are associated with the solar rotation are very similar in length to the biological periodicities. W e investigate the temporal relations of variations in solar activity a nd in biological systems to test associations between events in the IM F, in geomagnetic disturbance, in myocardial infarction and in physiol ogy. By cross-spectral analysis, we also find relations at certain fre quencies between changes in human physiology on the one hand, and (1) the vertical component of the induction vector of the IMF, B-z, and (2 ) a global index of geomagnetic disturbance, Kp, on the other hand, We wish to stimulate interest in these periodicities of both biological systems and geophysical endpoints among physicists and biologists alik e, so that problems relevant to clinicians and other biologists, inclu ding evolutionists, are eventually solved by their cooperation with th e geophysical community.