It is really too few species to have a sufficiently powerful test for phylogenetic signal. See Blomberg et al. (2003), available on my website.
Cheers, Ted Theodore Garland, Jr. Professor Department of Biology University of California, Riverside Riverside, CA 92521 Office Phone: (951) 827-3524 Wet Lab Phone: (951) 827-5724 Dry Lab Phone: (951) 827-4026 Home Phone: (951) 328-0820 Facsimile: (951) 827-4286 = Dept. office (not confidential) Email: tgarl...@ucr.edu http://www.biology.ucr.edu/people/faculty/Garland.html Experimental Evolution: Concepts, Methods, and Applications of Selection Experiments. 2009. Edited by Theodore Garland, Jr. and Michael R. Rose http://www.ucpress.edu/book.php?isbn=9780520261808 (PDFs of chapters are available from me or from the individual authors) ________________________________________ From: r-sig-phylo-boun...@r-project.org [r-sig-phylo-boun...@r-project.org] on behalf of Rob Lanfear [rob.lanf...@gmail.com] Sent: Wednesday, March 14, 2012 8:18 PM To: r-sig-phylo Subject: [R-sig-phylo] Testing for phylogenetic signal in proportions Hi All, I've tried searching the literature for this but the search terms tend to give irrelevant papers, so I thought I'd ask for some guidance here. I have a set of 11 species, an ultrametric tree for the species, and for each species I have a set of proportional data for 5 chemical traits. E.g. for spp1 my data might be: chemicalA=10%, chemicalB=50%, chemicalC=1%, chemicalD=19%, chemicalE=20%. The set of traits for each species always sums to 100%, but I don't know, and can't measure, the absolute values of the traits. Biologically speaking, this is OK, because it's the proportions that I'm interested in. I want to test for phylogenetic signal in these traits, and estimate the rate of change of each proportion along the phylogeny. Can anyone point me to any appropriate references for the methods and pitfalls of attempting to do this with proportion data? I can see that proportional data will have some odd properties (non-independence of traits, bounded (i.e. non-Brownian) evolution, etc.), but the best way of accounting for these is not immediately apparent to me. Thanks, Rob -- Rob Lanfear Research Fellow, Ecology, Evolution, and Genetics, Research School of Biology, Australian National University Tel: +61 2 6125 4321 www.robertlanfear.com [[alternative HTML version deleted]] _______________________________________________ R-sig-phylo mailing list R-sig-phylo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-phylo _______________________________________________ R-sig-phylo mailing list R-sig-phylo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
