This book is the first in a new series entitled ''Advances in Circadian Physiology." Our aim in this and subsequent volumes is to document and critically analyze the state of knowledge on biological clocks, circadian rhythms and their applications to human health, safety, performance and productivity. In the past twenty years, scientists have uncovered an elegant system of biological clocks in the brain that govern the daily rhythms of sleep and alertness, hormone levels and temperature and a myriad other aspects of body function. From the first identification of the suprachiasmatic...