Adaptive Significance of Circadian Clocks

@article{Sharma2003AdaptiveSO,
  title={Adaptive Significance of Circadian Clocks},
  author={Vijay Kumar Sharma},
  journal={Chronobiology International},
  year={2003},
  volume={20},
  pages={901 - 919}
}
  • V. Sharma
  • Published 1 January 2003
  • Biology, Psychology
  • Chronobiology International
Circadian clocks are ubiquitous and are found in organisms ranging from bacteria to mammals. This ubiquity of occurrence implies adaptive significance, but to date there has been no rigorous empirical evidence to support this. It is believed that an organism possessing circadian clocks gains fitness advantage in two ways: (i) by synchronizing its behavioral and physiological processes to cyclic environmental factors (extrinsic adaptive value); (ii) by coordinating its internal metabolic… 
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References

SHOWING 1-10 OF 127 REFERENCES
The Significance of Circadian Organization for Longevity in the Golden Hamster
TLDR
Longevity in hamsters is decreased with a noninvasive disruption of rhythmicity and is increased in older animals given suprachiasmatic implants that restore higher amplitude rhythms, substantiating the importance of the temporal organization of physiology and behavior provided by the circadian clock to the health and longevity of an organism.
Adaptive significance of a circadian clock: temporal segregation of activities reduces intrinsic competitive inferiority in Drosophila parasitoids
TLDR
It is demonstrated that temporal segregation of competing species could be endogenously controlled, which undoubtedly favours their coexistence in nature and also shows how natural selection can act on biological clocks to shape daily activity patterns.
Circadian rhythms in a nutshell.
  • I. Edery
  • Biology
    Physiological genomics
  • 2000
TLDR
The roles circadian clocks play in nature, how they might have arisen, human health concerns related to clock dysfunction, and mainly focuses on the clockworks found in Drosophila and mice, the two best studied animal model systems for understanding the biochemical and cellular bases of circadian rhythms.
Clocks, Genes and Evolution: The Evolution of Circadian Organization
TLDR
It is suggested that a long-term research programme combining selection studies on replicated sets of laboratory populations with a careful study of fitness effects of different light regimes on such populations is likely to prove far more fruitful than some of the approaches previously followed.
Molecular components of the circadian system in Drosophila.
TLDR
It has, however, become clear that in addition to the brain clock, autonomous or semi-autonomous clocks occur in peripheral tissues where they confer circadian regulation on specific functions.
Effects of Circadian Mutations and LD Periodicity on the Life Span of Drosophila melanogaster
TLDR
Evidence is found for an interaction between genotype and LD schedule in determining life span in Drosophila melanogaster mutants, consistent with the importance of the circadian clock in maintaining internal temporal order independent of environ-mental cycles.
Persistence of Eclosion Rhythm in Drosophila melanogaster After 600 Generations in an Aperiodic Environment
TLDR
It is shown that the circadian eclosion rhythm persists in a population of the fruitfly Drosophila melanogaster maintained in constant conditions of light, temperature, and humidity for over 600 generations, suggesting that even in the absence of any environmental cycle there exists some intrinsic fitness value of circadian rhythms.
Circadian Rhythms Confer a Higher Level of Fitness to Arabidopsis Plants1
TLDR
It is demonstrated that CCA1-ox plants retain the ability to respond to diurnal changes in light, and two other circadian rhythm mutants, LHY-ox and elf3, have low-viability phenotypes.
The current state and problems of circadian clock studies in cyanobacteria.
Circadian rhythms have been observed in innumerable physiological processes in most of organisms. Recent molecular and genetic studies on circadian clocks in many organisms have identified and
Life before the Clock: Modeling Circadian Evolution
TLDR
The authors hypothesize that those mechanisms that allowed synchronization in spite of metabolic complexity form the basis for the evolution of circadian properties and are as fundamental to the circadian system as the transcriptional/translational feedback loop.
...
1
2
3
4
5
...