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Simulating trees with a fixed number of extant species
1Institut für Integrative Biologie, ETH Zürich, Universitätsstr. 16, 8092 Zürich, Switzerland. tanja.stadler@env.ethz.ch
Systematic Biology
|April 13, 2011
Summary
This study introduces R-package TreeSim for simulating phylogenetic trees with a fixed number of species. It shows mass extinctions are hard to distinguish from stasis using only extant species data.
Area of Science:
- Phylogenetics
- Computational Biology
- Evolutionary Biology
Background:
- Simulating phylogenetic trees is crucial for evolutionary studies.
- Existing models may not accurately capture complex evolutionary events like mass extinctions or rate shifts.
- Distinguishing between different macroevolutionary scenarios from extant species data alone is challenging.
Purpose of the Study:
- To develop efficient simulation tools for phylogenetic trees with a fixed number of extant species.
- To introduce a new birth-death model incorporating mass extinction and rate shift events.
- To assess the distinguishability of mass extinction events from stasis using simulated trees.
Main Methods:
- Development of an open-source R-package, TreeSim, for phylogenetic tree simulations.
- Implementation of a constant rate birth-death process with mass extinction and/or rate shift events.
- Utilizing simulation tools to analyze trees with a fixed number of extant species.
Main Results:
- A mass extinction event is indistinguishable from a period of stasis using trees of only extant species.
- The developed simulation tools enable distinguishing between mass extinction and stasis when paleontological data is considered.
- Fast simulations facilitate the inference of speciation and extinction rates via approximate Bayesian computation.
Conclusions:
- Phylogenetic tree simulations with fixed extant species numbers are essential for understanding macroevolutionary dynamics.
- The TreeSim package provides valuable tools for evolutionary biologists.
- Distinguishing between mass extinction and stasis requires careful consideration of simulation models and available data types (extant vs. paleontological).
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