As the below vertebrate phylogenetic tree diagram example suggests, Vertebrates (backboned animals) are part of the wider group Chordata (see Phylogeny and Evolution of Chordates), characterized by the possession of an axial stiffening rod (notochord), a perforated pharynx, a dorsal hollow nerve cord, and a post-anal tail. The free vertebrate phylogenetic tree template shows how the phylogenetic system accurately reflects the evolutionary history of Vertebrates but requires recognition of unfamiliar characters, notably the number and position of openings in the skull. It should be noted here that a phylogenetic tree is a branching diagram or a tree showing the evolutionary relationships among various biological species or other entities based upon similarities and differences in their physical or genetic characteristics.
