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Lagrange-NG: The next generation of Lagrange
Ben Bettisworth1, Stephen A Smith2, Alexandros Stamatakis1,3
1Computational Molecular Evolution Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.
A new tool, Lagrange-NG, significantly speeds up biogeographical analyses using the Dispersion Extinction and Cladogensis (DEC) model. This enhanced computational efficiency allows for more complex phylogenetic and biogeographic studies with a greater number of regions.
Area of Science:
- Biogeography
- Phylogenetics
- Computational Biology
Background:
- The Dispersion-Eradication and Cladogenesis (DEC) model is crucial for biogeographical analyses but computationally intensive due to matrix exponentiation.
- The exponential increase in states with more regions limits the scale of biogeographical studies.
- Existing tools like Lagrange face performance bottlenecks, restricting analyses to fewer regions.
Purpose of the Study:
- To develop a computationally efficient version of the Lagrange tool for biogeographical analyses.
- To overcome the limitations imposed by the number of regions in DEC model computations.
- To enable larger-scale biogeographical and phylogenetic research.
Main Methods:
- Redesigned the Lagrange tool, naming it Lagrange-NG, incorporating a novel matrix exponential computation method using Krylov subspaces.
- Enabled multithreading for significant performance improvements.
- Introduced a new metric for assessing differences between range inferences in phylogenetic trees.
Main Results:
- Lagrange-NG achieves speedups of up to 49x with multithreading and 26x on a single thread compared to the original Lagrange.
- The tool can now analyze datasets with up to 12 regions in approximately 18 minutes.
- Lagrange-NG shows improved software quality, with a SoftWipe score increasing from 5.5 to 7.8.
Conclusions:
- Lagrange-NG offers a substantial advancement in computational efficiency for biogeographical analyses using the DEC model.
- The tool's speed and improved accuracy metrics facilitate more extensive and complex phylogenetic and biogeographical research.
- Lagrange-NG is freely available, promoting wider adoption and scientific progress in the field.
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