Introduction to Chronobiology
- 1Department of Biological Sciences, and Center for the Basis of Neural Cognition Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
- 2Division of Sleep and Circadian Disorders, Department of Medicine, Brigham and Women’s Hospital and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts 02115; and Morehouse School of Medicine, Atlanta, Georgia 30310
- 3Division of Sleep and Circadian Disorders, Department of Medicine, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts 02115
- Correspondence: skuhlman{at}cmu.edu; jduffy{at}research.bwh.harvard.edu
Abstract
A diverse range of species, from cyanobacteria to humans, evolved endogenous biological clocks that allow for the anticipation of daily variations in light and temperature. The ability to anticipate regular environmental rhythms promotes optimal performance and survival. Herein we present a brief historical timeline of how circadian concepts and terminology have emerged since the early observation of daily leaf movement in plants made by an astronomer in the 1700s.
