Towards a mechanistic foundation of evolutionary theory

  1. Michael Doebeli  Is a corresponding author
  2. Yaroslav Ispolatov
  3. Burt Simon
  1. University of British Columbia, Canada
  2. Universidad de Santiago de Chile, Chile
  3. University of Colorado, Denver, United States

Abstract

Most evolutionary thinking is based on the notion of fitness and related ideas such as fitness landscapes and evolutionary optima. Nevertheless, it is often unclear what fitness actually is, and its meaning often depends on the context. Here we argue that fitness should not be a basal ingredient in verbal or mathematical descriptions of evolution. Instead, we propose that evolutionary birth-death processes, in which individuals give birth and die at ever-changing rates, should be the basis of evolutionary theory, because such processes capture the fundamental events that generate evolutionary dynamics. In evolutionary birth-death processes, fitness is at best a derived quantity, and owing to the potential complexity of such processes, there is no guarantee that there is a simple scalar, such as fitness, that would describe long-term evolutionary outcomes. We discuss how evolutionary birth-death processes can provide useful perspectives on a number of central issues in evolution.

Article and author information

Author details

  1. Michael Doebeli

    Department of Zoology, University of British Columbia, Vancouver, Canada
    For correspondence
    doebeli@zoology.ubc.ca
    Competing interests
    Michael Doebeli, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5975-5710
  2. Yaroslav Ispolatov

    Departamento de Fisica, Universidad de Santiago de Chile, Santiago, Chile
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0201-3396
  3. Burt Simon

    Department of Mathematical and Statistical Sciences, University of Colorado, Denver, Denver, United States
    Competing interests
    No competing interests declared.

Funding

Natural Sciences and Engineering Research Council of Canada (219930)

  • Michael Doebeli

Fondo Nacional de Desarrollo Científico y Tecnológico (1151524)

  • Yaroslav Ispolatov

John Simon Guggenheim Memorial Foundation

  • Michael Doebeli

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Wenying Shou, Fred Hutchinson Cancer Research Center, United States

Publication history

  1. Received: December 3, 2016
  2. Accepted: February 13, 2017
  3. Accepted Manuscript published: February 15, 2017 (version 1)
  4. Version of Record published: March 2, 2017 (version 2)
  5. Version of Record updated: March 3, 2017 (version 3)

Copyright

© 2017, Doebeli et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Michael Doebeli
  2. Yaroslav Ispolatov
  3. Burt Simon
(2017)
Towards a mechanistic foundation of evolutionary theory
eLife 6:e23804.
https://doi.org/10.7554/eLife.23804
  1. Further reading

Further reading

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