Once a tip has been added to the tree, print the subtree to which the tip was added. The output of this function is printed for use as a RevBayes clade constraint object.
Examples
mrca_list <- c("Ursus_arctos", "Ursus_spelaeus", "Ursus_americanus")
clade_constraint <- echo_rb(tree, mrca_list, "Ursus_abstrusus")