Traditional Classification vs Phylogenetic (using Fish as an Example)

Traditional classification

Traditional spindle diagram of the evolution of the vertebrates at CLASS level

Conventional classification has living vertebrates grouped into seven CLASSES based on traditional interpretations of gross anatomical and physiological traits. This classification is the one most commonly encountered in school textbooks, overviews, non-specialist, and popular works. The extant vertebrates are:

  • Subphylum Vertebrata: 7 Classes (often taught as 5 Vertebrate Classes, by collapsing the 3 fish classes into one)

In addition to these, there are two classes of extinct armoured fishes, the Placodermi and the Acanthodii, both of which are considered paraphyletic.

Add Info on Phylogenetic (using Fish as an Example)