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Re: Stormbergia dangershoeki, new Early Jurassic ornithischian from South Africa

[Excuse cross-posting to Dinosaur and PhyloCode lists.]

> Date: Sun, 09 Oct 2005 10:53:04 -0700
> From: "T. Michael Keesey" <keesey@gmail.com>
> Sereno (1997) considered [_Ornithopoda_] a node-based clade, and
> anchored it on _Heterodontosaurus_ and _Parasaurolophus_ (1998), but
> in the latest edition of The Dinosauria, it is "all cerapodans
> closer to _Edmontosaurus_ than to _Triceratops_", which explicitly
> excludes _Marginocephalia_ (or at very least one genus therein).
> [...]
> To me it seems like a bad idea for now to anchor any major clade on
> heterodontosaurids. Better to use _Ornithopoda_ in the stem-based
> sense than to have it be an unstable clade that may include
> marginocephalians and even thyreophorans.

Is it just me, or does anyone else feel uncomfortable about the idea
that, once the PhyloCode is implemented, there will be a much stronger
tendency to respect strict priority in the definitions of clades, so
that we don't have the kinds of options that Mike and Tim are arguing
about here?

I love the fact that the PhyloCode infrastructure includes an on-line
register of published clade names and definitions, but I find myself
wondering whether it would be better if the register listed _all_
published definitions of eacdh name rather than just the first (and
only, if the recommendations are followed).

 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor  <mike@miketaylor.org.uk>  http://www.miketaylor.org.uk
)_v__/\  "I have no problem with [Microsoft's] success.  I have a problem
         with the fact that they just make really third-rate products"
         -- Steve Jobs.