[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

maniraptor taxonomy, etc.




From: "T. Mike Keesey" <tmk@dinosauricon.com>
To: Ken Kinman <kinman@hotmail.com>
CC: dinosaur@usc.edu
Subject: Re: eggshells, therizinosaurs & tyrannosaurs
Date: Wed, 19 Jul 2000 19:58:06 -0400 (EDT)

On Wed, 19 Jul 2000, Ken Kinman wrote:

> I can understand why Sereno's neologisms might irritate you, but given human nature and the peculiarities of phylogenetic taxonomy, it's bound to happen again and again.

This is being taken under consideration for PhyloCode
<http://www.ohiou.edu/phylocode/index.html>.

My fear is that the PhyloCode will only prolong the agony and delay some form of cladisto-eclectic system coming into use. In the meantime, the cladisto-eclectic war will continue to sap much of our productivity (unnecessarily in my view).
***************************************************
>  Just one more reason for me to dislike such anchoring.

But if they were anchored on the eponymous genera (or specifically, on the type specimen of the type species of the eponymous genera), would there be a problem?

Yes. A good idea, but it only solves one small problem. Call me old-fashioned, but I just prefer "characterizing" taxa rather than "defining" them. Both approaches have drawbacks, but I think the former is best for the long term. Mammalia based on the three auditory ossicles is far more useful than one anchored on fossil-poor monotremes (in the past, present, and the forseeable future).
*********************************************************
> Anyway, this demonstrates how phylogenetic taxonomy can increase confusion, rather than minimizing it, even in the long run.

No, only that misusing it can create confusion. The same goes for traditional taxonomy.

> Sorry, but I still think an occasional semi-paraphyletic group is preferable to a purely cladistic Tower of Babel.

It's only a Tower of Babel when priority is ignored or definitions are made not considering alternate phylogenies.

Just like Ashlock and Mayr, I believe purely cladistic classifications are inherently less stable and less useful (and the misuses are just making a bad situation even worse). In my view, it's worse than misusing a tool---it's using the "wrong" tool (like using hammers on screws---you'll get them into the wall, but they won't be very secure).
****************************************************
> and that doesn't even include those cases that don't distinguish between "non-avian" Maniraptora and the broader cladistic Maniraptora.

There is only cladistic Maniraptora. It was coined by Gauthier as a phylogenetic taxon, and has not been used, TMK, in traditional taxonomy. Excluding Aves from Maniraptora would undermine the entire original intent
of the taxon, to show that birds and dromaeosaurids share more recent ancestry with each other than with ornithomimids.

But if you put in a Kinman marker {{Aves}} within Maniraptora (as sister group to Family Dromaeosauridae), you accomplish the same thing---without all the various problems of traditional eclectic or traditional cladistic classifications. I believe Michael Benton did something like this in his 1997 book---classifying Aves separately from dinosaurs, but putting in a similar sort of cross-referencing marker (but without the distinctive double brackets).

______________________________________________________________________
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com