Detecting (non)parallel evolution in multidimensional spaces: angles, correlations and eigenanalysis.
View / Open Files
Authors
Publication Date
2022-02Journal Title
Biol Lett
ISSN
1744-9561
Publisher
The Royal Society
Volume
18
Issue
2
Language
eng
Type
Article
This Version
VoR
Metadata
Show full item recordCitation
Watanabe, J. (2022). Detecting (non)parallel evolution in multidimensional spaces: angles, correlations and eigenanalysis.. Biol Lett, 18 (2) https://doi.org/10.1098/rsbl.2021.0638
Abstract
Parallelism between evolutionary trajectories in a trait space is often seen as evidence for repeatability of phenotypic evolution, and angles between trajectories play a pivotal role in the analysis of parallelism. However, properties of angles in multidimensional spaces have not been widely appreciated by biologists. To remedy this situation, this study provides a brief overview on geometric and statistical aspects of angles in multidimensional spaces. Under the null hypothesis that trajectory vectors have no preferred directions (i.e. uniform distribution on hypersphere), the angle between two independent vectors is concentrated around the right angle, with a more pronounced peak in a higher-dimensional space. This probability distribution is closely related to t- and beta distributions, which can be used for testing the null hypothesis concerning a pair of trajectories. A recently proposed method with eigenanalysis of a vector correlation matrix can be connected to the test of no correlation or concentration of multiple vectors, for which simple test procedures are available in the statistical literature. Concentration of vectors can also be examined by tools of directional statistics such as the Rayleigh test. These frameworks provide biologists with baselines to make statistically justified inferences for (non)parallel evolution.
Keywords
Parallel Evolution, High-dimensional Data, Directional Statistics, Phenotypic Trajectory Analysis, Allometric Space
Sponsorship
Japan Society for the Promotion of Science (Overseas Research Fellowships (202160529))
Royal Society (Newton International Fellowships (NIF\R1\180520))
Identifiers
35168376, PMC8847891
External DOI: https://doi.org/10.1098/rsbl.2021.0638
This record's URL: https://www.repository.cam.ac.uk/handle/1810/335234
Statistics
Total file downloads (since January 2020). For more information on metrics see the
IRUS guide.