Figure 3. Changing k does not change the structure of the tree.

Neighbor joining phylogenetic trees constructed from pairwise Euclidean distances between oligonucleotide usage deviation vectors for 60 mycobacteriophage genomes. Trees from k equal to two, five and seven are shown here. Trees show a high degree of similarity regardless of the k used. Trends observed in the tetranucleotide usage based tree ( Figure 2), such as grouping of subcluster members into monophyletic clades, are conserved in these trees.