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traditional eclecticism wasn't explicit (too murky)



Nick wrote:
I believe putting birds in a category with the same rank as all of the rest of Dinosauria implies that all members of the bird category are related equally to all members of the dinosaur category, and that we know not to be true.
Nick:
That is why in the Kinman System, if one creates a paraphyletic group like Dinosauria, one must place an {{Aves}} marker within dinosaurian classifications, placed beside the dinosaur group you believe to be their closest relatives. Michael J. Benton did something similar in his recent 1997 book, which I was very happy to see (although he didn't use anything like explicit double brackets).
Furthermore, the paraphyleticism is also reflected in paraphyletic coding (which I haven't brought up in this list yet):
3 Ornithischiformes
4 Saurischiformes
_a_ {{Aves}}
The underlined "a" code shows that birds have been paraphyletically remove from Saurischiformes (sorry, I only know how to actually underline the "a" on Apple computers).
Therefore, although traditional eclectic classifications can be criticized as implying that birds are equally related to all dinosaurs, the required markers in the Kinman System explicitly show a relationship to a particular subset of saurischians. If I actually believed birds were equally related to all saurischians, I would have coded the {{Aves}} marker with number 5 (rather than _a_), showing a sister group relationship between Saurischiformes and Aves.
Within Saurischiformes, different workers might have different ideas where to place the {{Aves}} marker: as sister group to Dromaeosauridae, or sister group to Troodontidae, or sister group of a Dromaeosaur-Troodont clade (Sereno, 1999).
The IMPORTANT point is that the Kinman System only formally recognizes those clades which almost everyone agrees upon (Aves, Dromaeosauridae, Troodontidae). But different workers can arrange and code them slightly differently to reflect different viewpoints. Therefore the formal classification (clades that most agree upon) is stabilized, and the quibbling among the experts (about exactly how they are related) is reflected in an easily modified code.
------Ken Kinman


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