1 2
Home About us MoEF Contact us Sitemap Tamil Website  
About Envis
Whats New
Research on Microbes
Microbiology Experts
Online Submission
Access Statistics

Site Visitors

blog tracking

Journal of Comparative Physiology B
Vol. 186 (8), 2016, Pages: 947–968

Life in a dark biosphere: a review of circadian physiology in “arrhythmic” environments

Andrew David Beale, David Whitmore, Damian Moran

Department of Cell and Developmental Biology, Centre for Cell and Molecular Dynamics, University College London, London, UK.


Most of the life with which humans interact is exposed to highly rhythmic and extremely predictable changes in illumination that occur with the daily events of sunrise and sunset. However, while the influence of the sun feels omnipotent to surface dwellers such as ourselves, life on earth is dominated, in terms of biomass, by organisms isolated from the direct effects of the sun. A limited understanding of what life is like away from the sun can be inferred from our knowledge of physiology and ecology in the light biosphere, but a full understanding can only be gained by studying animals from the dark biosphere, both in the laboratory and in their natural habitats. One of the least understood aspects of life in the dark biosphere is the rhythmicity of physiology and what it means to live in an environment of low or no rhythmicity. Here we describe methods that may be used to understand rhythmic physiology in the dark and summarise some of the studies of rhythmic physiology in “arrhythmic” environments, such as the poles, deep sea and caves. We review what can be understood about the adaptive value of rhythmic physiology on the Earth’s surface from studies of animals from arrhythmic environments and what role a circadian clock may play in the dark.

Keywords: Circadian clock, Physiology, Arrhythmic, Cave, Subterranean, Evolution.

Copyright © 2005 ENVIS Centre ! All rights reserved
This site is optimized for 1024 x 768 screen resolution