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

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"
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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