Environmental Fluctuations and Level of Density-Compensation Strongly Affects the Probability of Fixation and Fixation Times
Author
Summary, in English
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.
Publishing year
2011
Language
English
Pages
1666-1681
Publication/Series
Bulletin of Mathematical Biology
Volume
73
Issue
7
Document type
Journal article
Publisher
Springer
Topic
- Biological Sciences
Keywords
- Probability of fixation
- Wright-Fisher model
- Population dynamics
- Temporal autocorrelation
- Carrying capacity
Status
Published
Research group
- Theoretical Population Ecology and Evolution Group
ISBN/ISSN/Other
- ISSN: 1522-9602