Using treemaps to visualize phylogenetic trees

Abstract

Over recent years the field of phylogenetics has witnessed significant algorithmic and technical progress. A new class of efficient phylogeny programs allows for computation of large evolutionary trees comprising 500-1.000 organisms within a couple of hours on a single CPU under elaborate optimization criteria. However, it is difficult to extract the valuable information contained in those large trees without appropriate visualization tools. As potential solution we propose the application of treemaps to visualize large phytogenies (evolutionary trees) and improve knowledge-retrieval. In addition, we propose a hybrid tree/treemap representation which provides a detailed view of subtrees via treemaps while maintaining a contextual view of the entire topology at the same time. Moreover, we demonstrate how it can be deployed to visualize an evolutionary tree comprising 2.415 mammals. The respective software package is available on-line at www.ics.forth.gr/~stamatak. © Springer-Verlag Berlin Heidelberg 2005.