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The Effect of Nonreversibility on Inferring Rooted Phylogenies.
Svetlana Cherlin1, Sarah E Heaps2, Tom M W Nye2
1Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.
Molecular Biology and Evolution
|November 18, 2017
Summary
Phylogenetic models often assume evolutionary processes are reversible, hindering root inference. This study introduces nonreversible models to accurately infer the root position in evolutionary trees, improving phylogenetic analysis.
Area of Science:
- Evolutionary Biology
- Phylogenetics
- Computational Biology
Background:
- Phylogenetic models commonly assume stationary and reversible evolutionary processes.
- These assumptions are biologically unrealistic and prevent root inference, which is crucial for interpreting evolutionary relationships.
Purpose of the Study:
- To investigate the impact of relaxing the reversibility assumption in phylogenetic models.
- To develop and evaluate new hierarchical models that allow for nonreversible evolutionary processes and enable root inference.
Main Methods:
- Proposed two hierarchical Bayesian models incorporating nonreversibility.
- Employed Markov chain Monte Carlo (MCMC) methods for phylogenetic inference.
- Tested models on simulated data with varying topological priors and real biological datasets (yeast radiation, ribosomal tree of life).
Main Results:
- Demonstrated the utility of nonreversible models in inferring root position from both simulated and real biological data.
- Successfully applied the models to datasets with known and controversial root positions.
- Showcased the effectiveness of the proposed models in phylogenetic analysis.
Conclusions:
- Relaxing the reversibility assumption is essential for accurate phylogenetic root inference.
- The proposed nonreversible models are effective tools for determining root position in evolutionary trees.
- These models offer improved phylogenetic interpretation, especially for controversial evolutionary histories.
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