The rhythms of life and in physical science are all around us. We are especially aware of these in the summer in Oklahoma where the rhythmic song of the cicada rings in our ears. When the temperature rises or falls the rate of chirping increases or decreases and if we have been around long enough we notice that the number of these crickets has a population variation with a cycle of something like 17 years. These rhythms and others, such as our sleep rhythm, affect us every day. From a study of these circadian rhythms we may learn how important biological and physical factors help determine our daily lives. We may also learn how to manipulate both human and physical systems for good.
Just as the ancients found the origin of the sine function in their plotting of the motions of stars and as they plotted out the movements of planets found an understanding of mathematics, so we may find a helpful description of these rhythmic processes using mathematics based on our observation of circadian rhythms.
A Pretty Picture of Elk-for no particular reason!