An equivalent characterization of a tree is that the root node has no predecessors and every other node has exactly one predecessor (Even 1979). Typical examples of trees that ... the root at the left ...

This diagram is an example of a simple phylogenetic tree. In most cases, researchers draw phylogenetic trees in such a way as to record only those events that are relevant to a set of living taxa.

Lessons on language families are often illustrated with a simple tree diagram that has all the information but lacks imagination. There’s no reason linguistics has to be so visually uninspiring.