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What affects power to estimate speciation rate shifts?
Ullasa Kodandaramaiah1, Gopal Murali1
1IISER-TVM Centre for Research and Education in Ecology and Evolution (ICREEE), School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, India.
This study evaluated three methods (BiSSE, MEDUSA, BAMM) for detecting speciation rate shifts in evolutionary biology. High speciation rate asymmetry and large lineage sizes generally improved detection power for all methods.
Area of Science:
- Evolutionary Biology
- Phylogenetics
- Diversification Analysis
Background:
- Estimating speciation and extinction rates from phylogenies aids in understanding diversification drivers.
- Researchers frequently test trait evolution's impact on speciation rates using methods like BiSSE, MEDUSA, and BAMM.
- Evaluating the performance of these diversification modeling methods is crucial for reliable evolutionary inference.
Purpose of the Study:
- To assess the power of BiSSE, MEDUSA, and BAMM in detecting single speciation rate shifts.
- To investigate how factors like rate asymmetry, lineage size, and tip-ratio bias affect shift detection.
- To provide practical recommendations for users of these diversification modeling techniques.
Main Methods:
- Simulated time-calibrated phylogenies, each with a single speciation rate shift.
- Varied parameters including speciation rate asymmetry, number of tips, tip-ratio bias, and timing of the rate shift.
- Compared the power of BiSSE, MEDUSA, and BAMM to detect these simulated shifts.
Main Results:
- All three methods demonstrated good power to detect rate shifts when speciation rate asymmetry was high and lineage sizes were large.
- High rate asymmetry maintained good detection power even with smaller lineage sizes.
- BAMM performance was most affected by small lineage sizes, while tip-ratio bias impacted rate estimation accuracy more than detection power.
Conclusions:
- BiSSE, MEDUSA, and BAMM are generally effective for detecting speciation rate shifts, particularly under strong asymmetry and large lineages.
- Users should be mindful of lineage size, especially when employing BAMM.
- The study offers guidance for optimizing the application of these diversification modeling tools in evolutionary research.
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