Re: Dino Birds (was Re: Dinosaur = extinct animal)

[Stanley Friesen <sarima@ix.netcom.com>]

At 11:12 AM 7/19/99 -0400, T. Mike Keesey wrote:
>But naming a traditional paraphyletic taxon can exclude other taxa (para-
>or monophyletic) from ever being recognized, whereas naming a phylogenetic
>taxon never precludes the possibility of naming other clades. No
>possibilities are ruled out. 
> 
This just doesn't seem like much of a problem to me.
If, by later analysis, it turns out that a different paraphyletic taxon is
more useful than the chosen one(s), then a taxonomic revision may be called
for.  This will likely result in accepting the new, previously "excluded"
group, and rejecting the previously conflicting one.  With proper
information-theoretic analysis, this should be relatively rare, however.
>This doesn't address the other terms. I find myself using "non-neornithean
>dinosaurs" at least as much as I use "non-avian dinosaurs". Under
>traditional taxonomy, one has to use the rather clumsy phrase
>"non-neornithean avians and dinosaurs".

Hmm, this depends a little on whether the non-neornithine birds have their
own taxon.  I suspect this may be likely, in which case the phrase would be
slightly nicer: dinosaurs and "paleornithines".

> "Non-maniraptoran dinosaurs" 
>becomes "non-maniraptoran dinosaurs and avians", etc. You gain efficiency
>for one, and only one, designation ("dinosaur" instead of "non-avian
>dinosaur"), and lose it for a thousand others. 

I find that only a small handful of these are needed more than on rare
occasions.
Most of those that are more needed can be formally recognized, leaving only
a very small handful of useful groupings formally unnamed.

--------------
May the peace of God be with you.         sarima@ix.netcom.com