TESTING FOR PHYLOGENETIC SIGNAL IN BIOLOGICAL TRAITS: THE UBIQUITY OF CROSS-PRODUCT STATISTICS
Article first published online: 6 NOV 2012
© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
Volume 67, Issue 3, pages 828–840, March 2013
How to Cite
Pavoine, S. and Ricotta, C. (2013), TESTING FOR PHYLOGENETIC SIGNAL IN BIOLOGICAL TRAITS: THE UBIQUITY OF CROSS-PRODUCT STATISTICS. Evolution, 67: 828–840. doi: 10.1111/j.1558-5646.2012.01823.x
- Issue published online: 5 MAR 2013
- Article first published online: 6 NOV 2012
- Accepted manuscript online: 16 OCT 2012 10:10AM EST
- Received May 8, 2012 Accepted September 18, 2012
- Abouheif test;
- Blomberg et al. K and K*;
- equivalent test statistic;
- Mantel test;
- Moran's I;
To evaluate rates of evolution, to establish tests of correlation between two traits, or to investigate to what degree the phylogeny of a species assemblage is predictive of a trait value so-called tests for phylogenetic signal are used. Being based on different approaches, these tests are generally thought to possess quite different statistical performances. In this article, we show that the Blomberg et al. K and K*, the Abouheif index, the Moran's I, and the Mantel correlation are all based on a cross-product statistic, and are thus all related to each other when they are associated to a permutation test of phylogenetic signal. What changes is only the way phylogenetic and trait similarities (or dissimilarities) among the tips of a phylogeny are computed. The definitions of the phylogenetic and trait-based (dis)similarities among tips thus determines the performance of the tests. We shortly discuss the biological and statistical consequences (in terms of power and type I error of the tests) of the observed relatedness among the statistics that allow tests for phylogenetic signal. Blomberg et al. K* statistic appears as one on the most efficient approaches to test for phylogenetic signal. When branch lengths are not available or not accurate, Abouheif's Cmean statistic is a powerful alternative to K*.