Evolutionary Systematics, also called Gradistic Taxonomy, gives an a dynamic evolutionary slant to the static Linnean system. It is based on a combination of branching and divergence. Most old books on palaeontology were based on this paradigm. Evolutionary Systematics was formulated by such "grand old men" of palaeontology as Ernst Mayr and G. G. Simpson. This approach accepts the Hennigian cladistic methodology as adequate for reconstructing phylogenetic trees, but retains paraphyletic groups (e.g. " Reptilia").
Also, unlike Cladistics, with it's reliance on a hypothetical Most Recent Common Ancestor that is never actually described or discovered (a missing link that is always missing), Evolutionary systematics gives illustrations of the actual evolution of one species or higher taxon into another (as illustrated by the graphic at the top of the page showing the evolution of fossil horses).
Admitedly, Evolutionary Systematics suffers from a number of shortcomings. For example the use of several very different criteria (phylogeny, divergence, adaptational level) to define particular taxa, as well as inconsistencies inherent in the paraphyletic approach (e.g. separating Class Aves (Birds) from the Archosauria). This, together with the greater rigour and precion of the and practical and heuristic superiority of the Cladistic (Phylogenetic) approach has meant that over the past decades.Evolutionary Systematics has greatly declined; the result being the rise of cladistics.as the dominant paradigm.
Apart from my own good self I have only found one defense of evolutionary
systematics on the Web - a lone voice in the wilderness, which you can
check out if you want: Stanley
Friesen explains why
I prefer an evolutionary classification.
Fossil Horses in Cyberspace is an excellent site that (among other things) gives a practical example of Evolutionary Systematics (as a methodology for the evolution of fossil horses). This the site that I got the kewl icon at the top of ths page from.
page historypage uploaded 13 November 1998