The network of similarities among the nearly universal trees (NUTs). (a) Each node (green dot) denotes a NUT, and nodes are connected by edges if the similarity between the respective edges exceeds the indicated threshold. (b) The connectivity of 102 NUTs and the 14 1:1 NUTs depending on the topological similarity threshold.
Puigbò et al. Journal of Biology 2009 8:59 doi:10.1186/jbiol159