Fig. 1

Properties of an evolutionary tree. An evolutionary tree consists of three basic components: internal nodes, lines, and terminal nodes. Lines are representations of lineages. Points where a lineage bifurcates are marked by internal nodes, representing the most recent common ancestor of all descending groups. Terminal nodes appear at the end of lineages and most regularly represent extant species or groups. Along the lines, apomorphies (evolutionary newly developed traits) can be displayed to emphasize and explain the bifurcation event. A nested hierarchy of clades (a common ancestor and all its descendants) is created by the bifurcations at internal nodes