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Re: AMARGASAURUS (& taxonomy generally)



Jaime,
If I understand correctly what you are saying, a way has already been found to "successfully distinguish and define these qualities together." At least it is a start (and it is called the Kinman System).
In my classification of prokaryotes, I not only have a marker for the eukaryotic host cell (within Class Crenarchaea), but also a marker for protomitochondria in Class Proteobacteracea, a marker for protochloroplasts in Class Coccogonea, and even a marker for protoperoxisomes in Class Posibacteracea. Reticulate evolution is no problem. In principle it could be extended to include the classification of genes (whose evolution is even more reticulate).
I have no trouble coding strict cladistic classifications (that's a piece of cake). But I also have no problem coding totally paraphyletic classifications either (although they are rare). If the strict cladists ever get a hold of the ammonoids, it going to be a royal mess. I have no problem showing Orde Anarcestida giving rise to Clymeniida and Goniatitida, and the latter giving rise to Prolecanitida, which gave rise to Ceratitida, which in turn gave rise to Ammonitida.
The problems and long-term confusion that would arise in converting this eclectic classification of ammonoids into a pure "cladification" would undoubtedly dwarf the taxonomy problems it has caused in dinosaurs.
Mother nature has indeed done us a favor by only giving us a tiny sliver of taxonomic diversity to classify, and plenty of big gaps where we can draw our arbitrary lines around taxa.
Unfortunately phylogenetic taxonomy, especially at higher taxonomic levels, has gone beyond what Hennig envisioned, and the automatic conversion of cladograms into strict cladifications (and ignoring the paraphyletic nature of speciation) will produce classifications so complex and confusing that cladistics will have to undergo another transformation, ending up (IMO) with something similar to the Kinman System. All classifications (including cladifications) are arbitrary, but I believe a cladisto-eclectic classification of will lead to classifications that are the least arbitrary, the most useful, and ultimately the most stable in the long-run.
------Ken Kinman
*****************************************************
Jaime wrote:
  Perhaps it is so frightening a concept to completely
abandon taxonomy based on the incomplete sampling of
the geological record and the simple fact that either
a branching tree with end products (successive
diversity) or nested ingrowth of lines to a common
trunk (interbreeding) may be both correct, and _no_
taxonomic hypothesis has so far found a way to
successfully distinguish and define these qualities
together. We would have to abandon our Dinosauria,
Mammalia, Aves, Bryozoa, Archaea, Echinodermata,
Arachnida, etc.; all that ... lost ... because either
competing hypothesis, nesting or branching, cannot
correctly show the distinction between genetic change
and mutation. Or how bacteria can literally pass genes
from one member of a generation to another, or
cross-generational, without fissioning (Lateral Gene
Transfer).

  What a frightening concept, but something has to be
realized that allows parent-child relationships to be
classified in the same manner as sibling-sibling
relationsips, or that allows two different
classificatory hypotheses to operate in the same system.

=====
Jaime "James" A. Headden

  Dinosaurs are horrible, terrible creatures! Even the
  fluffy ones, the snuggle-up-at-night-with ones. You think
  they're fun and sweet, but watch out for that stray tail
  spike! Down, gaston, down, boy! No, not on top of Momma!

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