Fig. 5

An illustration of one pass through the algorithm. The species tree S is left and \({\mathcal {G}}\) has two trees (middle) and partial mapping \(\alpha \) (labels are the lowercase of the species). Here \(\alpha \) is in a clean state, and the algorithm will pick a lowest minimal \(\bot \)-node (white circle) and try to map it to, say, H. The forest on the right is the state of \(\alpha \) after applying this and cleaning up