The format is:
List of 5
$ edge : int [1:10, 1:2] 7 8 9 10 11 11 10 9 8 7 ...
$ Nnode : int 5
$ tip.label : chr [1:6] "taxon_1" "taxon_2" "taxon_3" "taxon_4" ...
$ edge.length: num [1:10] 1 1 1 1 1 1 2 3 4 5
$ root.edge : num 1
- attr(*, "class")= chr "phylo"
- attr(*, "order")= chr "cladewise"