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Re: T-J Extinction event article (more media errors?)



George,
I couldn't agree more. And it's even more clear since someone (I'm not sure who) has given these "included clades" a name (exgroups). And clearer yet if you leave behind a marker for the exgroup within the inclusive clade (which renders its informationally complete---- or semi-holophyletic).
This is just "informative" cross-referencing, and any analogies to being partially pregnant completely miss the point. If you formally remove an included clade (exgroup) you should leave a marker there to document it. Cladists get their sister group information, eclecticists can have exgroups, and everyone's needs should be accomodated in a single classificaton system (once we finally shake off the notion that this is not possible).
---Ken Kinman
**********************************************************
From: Dinogeorge@aol.com
Reply-To: Dinogeorge@aol.com
To: dinosaur@usc.edu
Subject: Re: T-J Extinction event article (more media errors?)
Date: Fri, 11 May 2001 21:35:25 EDT

In a message dated 5/11/01 5:09:35 PM EST, david.marjanovic@gmx.at writes:

<< This is an example how the use of paraphyletic taxa can mislead. "Both"
have
living descendants, so they aren't extinct, even though no actual members of
the actual paraphyletic groups survive. >>


This is not misleading; but it may be confusing because the paraphyletic
groups under discussion have not been adequately defined. Define a
paraphyletic group as the difference between an  inclusive clade and one or
more of its included clades and there's no confusion.

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