GOBO::Phylo::PhyloNode

  printf '%s "%s"', $n->id, $n->label;

An GOBO::Node in a phylogenetic tree that represents some kind of evolvable entity

Note that the same entity (e.g. gene, species) can be present in multiple GOBO::Phylo::PhyloTree. It may have different parents in each.

This necessitates having a separate object to represent both (a) the node in the tree, together with its hypothetical placements and (b) the entity it represents. The 'represents' accessor links these.

The parent attribute can also be obtained from the tree object. Redundancy? Frame-style vs axiom-style