Fig. 3

GLaMST tree construction process. This example shows the first two iterations of an illustrative example. In each visualization, black nodes and solid arrows represent the reconstructed part of the lineage tree. White nodes represent observed sequences that are standing by and waiting to be incorporated into the reconstructed part of the lineage tree. The dotted lines represent the MST, which guides the algorithm in growing the reconstructed part of the lineage tree. a GLaMST is initialized by treating the root node as the reconstructed part and all other observed nodes as standing by. b An MST is constructed based on the pairwise edit-distance. c GLaMST selects the most frequent origination-operation pair to create and insert an intermediate node and grow the reconstructed part. d–f The second iteration of the process to insert another node to the reconstructed part