Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Molecular clock mirages.

F J Ayala1

  • 1Department of Ecology and Evolutionary Biology, University of California, Irvine 92697-2525, USA. fjayala@uci.edu

Bioessays : News and Reviews in Molecular, Cellular and Developmental Biology
|March 10, 1999
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

GEOGRAPHY OF THE SIBLING SPECIES RELATED TO DROSOPHILA WILLISTONI, AND OF THE SEMISPECIES OF THE DROSOPHILA PAULISTORUM COMPLEX.

Evolution; international journal of organic evolution·2017
Same author

Is Predominant Clonal Evolution a Common Evolutionary Adaptation to Parasitism in Pathogenic Parasitic Protozoa, Fungi, Bacteria, and Viruses?

Advances in parasitology·2017
Same author

Wineries, drosophila, alcohol, and Adh.

Oecologia·2017
Same author

Phylogenetic character mapping of RADES Probing, a new marker for exploring the clonal evolution of expressed coding sequences in Trypanosoma cruzi, the agent of Chagas disease.

Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases·2013
Same author

Climate change and the integrity of science.

Science (New York, N.Y.)·2010
Same author

Using mitochondrial and nuclear markers to evaluate the degree of genetic cohesion among Echinococcus populations.

Experimental parasitology·2008

The molecular clock hypothesis suggests constant evolutionary rates. However, experimental data reveal higher variance than predicted, indicating natural selection

Area of Science:

  • Evolutionary biology
  • Molecular evolution

Background:

  • The molecular clock hypothesis posits constant rates of molecular evolution across time and lineages.
  • Neutral theory predicts a Poisson process for molecular evolution, where mean and variance are equal.
  • Empirical data frequently demonstrate a higher variance than the mean (hypervariance).

Purpose of the Study:

  • To evaluate existing hypotheses proposed to explain the hypervariance observed in molecular evolution.
  • To determine if proposed predictive hypotheses for molecular evolution can be generally sustained.
  • To understand the underlying mechanisms driving molecular evolution rates.

Main Methods:

  • Analysis of four recent research papers investigating molecular evolution rates.
  • Comparison of experimental data against predictions from the neutral theory of molecular evolution.

Related Experiment Videos

  • Assessment of various hypotheses attempting to account for molecular hypervariance.

    • Main Results:

    • None of the recently proposed predictive hypotheses for molecular evolution could be generally maintained.
    • Experimental data consistently show that the variance in molecular evolution rates is typically larger than the mean.
    • Molecular evolution is influenced by natural selection, which is not a constant rate process.

    Conclusions:

    • The observed hypervariance in molecular evolution suggests it is not a simple Poisson process.
    • Natural selection appears to be a significant factor influencing the rates and patterns of molecular evolution.
    • Despite deviations, the accumulation of empirical data can lead to an approximate molecular clock due to convergence over large numbers.