One of the examples used in the present paper (see section 3.2) is based on the Genbank taxonomy (http://www. ncbi.nlm.nih.gov/sites/entrez?db=taxonomy). Please note that the Genbank taxonomy can not be considered as a conclusive phylogeny, as clearly stated by Genbank owners (http://www.ncbi.nlm.nih.gov/Taxonomy/ taxonomyhome.html/index.cgi?chapter=howcite). We are only looking here for a way to display any given hierarchical classification, whether it is considered as a phylogeny, a taxonomy or so.