Your browser version may not work well with NCBI's Web applications. More information here...
1: J Theor Biol. 2002 Jan 7;214(1):99-103.
Related Articles, Links
Click here to read
Evaluating phylogenetic tree shape: two modifications to Fusco & Cronk's method.

Purvis A, Katzourakis A, Agapow PM.

Department of Biological Sciences, Imperial College, Silwood Park, Ascot, Berkshire, SL5 7PY, UK. a.purvis@ic.ac.uk

Measurement of the degree of asymmetry in phylogenetic trees is important because a tree's shape reflects the process by which it has grown. For example, highly asymmetric trees are evidence that species have had different potential for diversification. Of the tree shape measures in the literature, that proposed by Fusco & Cronk (J. theor. Biol.175, 235-243) appears to be particularly useful, because it does not require fully-resolved trees whose terminals are of equal taxonomic rank. The value of the asymmetry or imbalance at a node is intended to be independent of the number of species ultimately descended from the node. In this paper, however, we point out that the value does depend upon species number. We propose two modifications that remove the dependency and so increase the measure's usefulness. We illustrate the use of the modified measures, which are implemented in a freely-available program, MESA. Copyright 2002 Academic Press.

Publication Types:
PMID: 11786035 [PubMed - indexed for MEDLINE]