Advanced

Environmental Fluctuations and Level of Density-Compensation Strongly Affects the Probability of Fixation and Fixation Times

Bjorklund, M.; Ranta, E.; Kaitala, V.; Bach, Lars LU and Lundberg, Per LU (2011) In Bulletin of Mathematical Biology 73(7). p.1666-1681
Abstract
The probability of, and time to, fixation of a mutation in a population has traditionally been studied by the classic Wright-Fisher model where population size is constant. Recent theoretical expansions have covered fluctuating populations in various ways but have not incorporated models of how the environment fluctuates in combination with different levels of density-compensation affecting fecundity. We tested the hypothesis that the probability of, and time to, fixation of neutral, advantageous and deleterious mutations is dependent on how the environment fluctuates over time, and on the level of density-compensation. We found that fixation probabilities and times were dependent on the pattern of autocorrelation of carrying capacity over... (More)
The probability of, and time to, fixation of a mutation in a population has traditionally been studied by the classic Wright-Fisher model where population size is constant. Recent theoretical expansions have covered fluctuating populations in various ways but have not incorporated models of how the environment fluctuates in combination with different levels of density-compensation affecting fecundity. We tested the hypothesis that the probability of, and time to, fixation of neutral, advantageous and deleterious mutations is dependent on how the environment fluctuates over time, and on the level of density-compensation. We found that fixation probabilities and times were dependent on the pattern of autocorrelation of carrying capacity over time and interacted with density-compensation. The pattern found was most pronounced at small population sizes. The patterns differed greatly depending on whether the mutation was neutral, advantageous, or disadvantageous. The results indicate that the degree of mismatch between carrying capacity and population size is a key factor, rather than population size per se, and that effective population sizes can be very low also when the census population size is far above the carrying capacity. This study highlights the need for explicit population dynamic models and models for environmental fluctuations for the understanding of the dynamics of genes in populations. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Probability of fixation, Wright-Fisher model, Population dynamics, Temporal autocorrelation, Carrying capacity
in
Bulletin of Mathematical Biology
volume
73
issue
7
pages
1666 - 1681
publisher
Springer
external identifiers
  • wos:000290671500011
  • scopus:79956127415
ISSN
1522-9602
DOI
10.1007/s11538-010-9587-3
language
English
LU publication?
yes
id
3f7314a1-201e-4d42-97d0-57065b763395 (old id 1986507)
date added to LUP
2011-06-29 11:52:12
date last changed
2017-05-28 03:15:13
@article{3f7314a1-201e-4d42-97d0-57065b763395,
  abstract     = {The probability of, and time to, fixation of a mutation in a population has traditionally been studied by the classic Wright-Fisher model where population size is constant. Recent theoretical expansions have covered fluctuating populations in various ways but have not incorporated models of how the environment fluctuates in combination with different levels of density-compensation affecting fecundity. We tested the hypothesis that the probability of, and time to, fixation of neutral, advantageous and deleterious mutations is dependent on how the environment fluctuates over time, and on the level of density-compensation. We found that fixation probabilities and times were dependent on the pattern of autocorrelation of carrying capacity over time and interacted with density-compensation. The pattern found was most pronounced at small population sizes. The patterns differed greatly depending on whether the mutation was neutral, advantageous, or disadvantageous. The results indicate that the degree of mismatch between carrying capacity and population size is a key factor, rather than population size per se, and that effective population sizes can be very low also when the census population size is far above the carrying capacity. This study highlights the need for explicit population dynamic models and models for environmental fluctuations for the understanding of the dynamics of genes in populations.},
  author       = {Bjorklund, M. and Ranta, E. and Kaitala, V. and Bach, Lars and Lundberg, Per},
  issn         = {1522-9602},
  keyword      = {Probability of fixation,Wright-Fisher model,Population dynamics,Temporal autocorrelation,Carrying capacity},
  language     = {eng},
  number       = {7},
  pages        = {1666--1681},
  publisher    = {Springer},
  series       = {Bulletin of Mathematical Biology},
  title        = {Environmental Fluctuations and Level of Density-Compensation Strongly Affects the Probability of Fixation and Fixation Times},
  url          = {http://dx.doi.org/10.1007/s11538-010-9587-3},
  volume       = {73},
  year         = {2011},
}