Checking taxonomic overlap of source phylogenies. An example of the output from stk_check_overlap. A) shows the source trees represented by nodes with an edge drawn between them when two taxa are shared between them. Tree 10 does not have sufficient taxonomic overlap and should therefore be excluded. B) shows the same set of source phylogenies, but with four taxa required as the minimum for taxonomic overlap. Now trees 10 and 18 should be excluded. In addition, note that the number of edges connecting each node has decreased accordingly.