Identify the root, if present, as the oldest common ancestor
Read branches from the root toward the tips
Treat each branching point as a common ancestor
Use the node closest to two taxa to find their most recent common ancestor
Interpret sister taxa as two lineages sharing an immediate common ancestor
Count branch points, not tip proximity, to determine relatedness
Ignore left-to-right order unless the tree is explicitly rooted and ordered
Compare branch lengths only if the tree includes a scale
Use branch length to infer amount of change or time when indicated
Recognize that rotating branches around a node does not change relationships
Identify clades as an ancestor and all of its descendants
Distinguish monophyletic groups from paraphyletic or polyphyletic groups
Check whether the tree is rooted or unrooted before interpreting ancestry
Use outgroup placement to infer the direction of evolution in rooted trees
Read taxon labels at the tips to identify the organisms being compared
Follow internal nodes to trace lineage splits
Compare the number of shared nodes to assess evolutionary closeness
Remember that taxa sharing a more recent common ancestor are more closely related
Do not assume that organisms at the same vertical or horizontal position are more closely related
Use the scale bar, if present, to estimate evolutionary distance or divergence time
Interpret polytomies as unresolved branching relationships
Verify whether the tree shows genetic change, time, or both before drawing conclusions