Message 2004-10-0185: RE: crown clade convention

Tue, 19 Oct 2004 11:39:16 -0700

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Date: Tue, 19 Oct 2004 11:39:16 -0700
From: [unknown]
To: "''" <phylocode@ouvaxa.cats.ohiou.=
Subject: RE: crown clade convention

Thanks for this Kevin (and Phil). Your well-argued posts have confirm=
ed my
thinking. A couple of final thoughts.

> In short, the crown convention asks paleontologists to make a
> sacrifice to achieve greater consistency between how both paleontol=
> and neontologists use widely known names.  Paleontologists are bein=
g asked
> to give up some of their logical and established traditions for the
> greater good of all biology.  The important point here is that ther=
e is no
> question that Jason is correct in arguing that using Tetrapoda for =
> apomorphy clade and Neotetrapoda for the crown is logically consist=
ent and
> in agreement with the way that paleontologists have traditionally u=
> these names.  The argument against this position is that it would b=
> better for biology as a whole to adopt conventions 1) that maximize
> consistency in the use of names among all biologists and 2) that us=
e the
> best known names for the clades about which biologists as a whole h=
ave the
> most to say.

The fact that Neotetrapoda hasn't been used isn't in my mind really s=
evidence since Gauthier, Kluge and Rowe formally ignored it in Phylog=
Nomenclature a mere 8 years after Gaffney suggested it, opting for th=
e crown
convention because of problems seen with apomorphy-based definitions =
argued by you and Jacques in 1990) that have subsequently been either
corrected or shown false. Neotetrapoda has never received the weight =
authority that either the 1988 paper or the publication of the compan=
volume would lend (which I see as a great opportunity to educate
nonsystematists as to the importance in precision of name use). Still=
, I see
your point.

What is "best for biology" is for everybody to mean the same thing wh=
en we
use a name, thus either the crown or apomorphy definition is suboptim=
al. In
the former case, there will be confusion engendered when "tetrapods" =
are no
longer "Tetrapods", which will not only be among paleontologists but =
the educated general public who read Jenny Clack's or Carl Zimmer's r=
books, and among neontologists who still consider tetrapods to be lim=
vertebrates even if some of their papers are less than precise. In th=
latter case, the confusion will continue to be as Michel and Kevin ha=
characterized it, with inaccurate statements entering the literature =
I still think is a by product of an overly pedantic, literal reading =
of this
literature). So the real question in my mind is how one determines wh=
confusion is potentially greater, and I'm not so sure how that is don=
objectively. At this stage preference for either option seems to be b=
ased on

Regarding your number 2, respectfully, there has been an awful lot of=
spilled over the clade of limbed vertebrates over the past ten years,
including in the neontological literature. Obviously biologists have =
a lot
to say about this group (which they call "Tetrapoda").



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