Figure 7
Simplification of an ABC gene tree, example for non-commutativity of rules. The original tree is shown on top, the automatically simplified tree at the bottom. In this example, applying paraphyletic compression first (simplifying the two marked nodes into one) and monophyletic compression later would have resulted in a further simplified subtree only composed of "Eukarya ABCE1 Pt: 1" and "Yeast ABCE Pt: 1". In other words, monophyletic and paraphyletic compression are not commutative.