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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Structured coalescent processes from a modified Moran model with large offspring numbers
1Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States. eldon@fas.harvard.edu
Theoretical Population Biology
|May 13, 2009
Summary
This study derives structured coalescent processes for finite island models, revealing that migration timescales influence genetic genealogy, impacting ancestral mergers and sample size calculations.
Area of Science:
- Population Genetics
- Theoretical Biology
- Mathematical Modeling
Background:
- Coalescent theory models genetic genealogy.
- Finite island models are used to study population structure.
- Migration patterns influence genetic diversity within and between subpopulations.
Purpose of the Study:
- To derive structured coalescent processes for finite island models with size-conserving migration.
- To investigate the impact of migration timescales on genetic genealogy.
- To explore conditions leading to multiple mergers of ancestral lines.
Main Methods:
- Derivation of structured coalescent processes.
- Analysis of a modified Moran model with variable offspring number.
- Examination of convergence under different migration timescales (coalescent vs. Wright-Fisher).
Main Results:
- Three distinct limit processes emerge based on migration timescale.
- Two processes allow for multiple mergers of ancestral lines.
- Expected time to the most recent common ancestor and genealogy size can be similar even with low migration if multiple mergers occur.
Conclusions:
- Migration timescale is crucial for structured coalescent processes.
- Multiple mergers can homogenize genealogical properties across subpopulations.
- Findings inform inference of genetic population structure and evolutionary history.
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