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Date: Mon, 10 Oct 2005 10:17:01 +0100 (BST)
From: [unknown]
To: keesey@gmail.com
Cc: dinosaur@usc.edu, phylocode@ouvaxa.cats.ohiou.edu
Subject: 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> >=20 > Sereno (1997) considered [_Ornithopoda_] a node-based clade, and > anchored it on _Heterodontosaurus_ and _Parasaurolophus_ (1998), bu= t > 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 stronge= r 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). _/|_=09 ____________________________________________________________= _______ /o ) \/ Mike Taylor <mike@miketaylor.org.uk> http://www.miketaylor= .org.uk )_v__/\ "I have no problem with [Microsoft's] success. I have a pro= blem =09 with the fact that they just make really third-rate products" =09 -- Steve Jobs.