Message 2004-10-0046: Re: Panstems

Mon, 13 Sep 2004 21:20:49 +0200

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Date: Mon, 13 Sep 2004 21:20:49 +0200
From: [unknown]
To: PML <phylocode@ouvaxa.cats.ohiou.edu>
Subject: Re: Panstems

----- Original Message -----
=46rom: "Mickey Mortimer" <Mickey_Mortimer111@msn.com>
Sent: Monday, September 13, 2004 8:10 PM

> Kevin de Queiroz wrote-
>
> > This is true in the sense that some non-Pan names have already be=
en
> defined as referring to total clades;
>
> Indeed, have any major total clades of vertebrates NOT
> been defined already by non-Pan names?

In the least resolved areas (base of Gnathostomata...), we might find=
 a few.
But not many. Here are a few counterexamples off the top of my head:

Crown        Panstem
*Latimeria*        Actinistia =3D Coelacanthida?
*Polypterus*        Cladistia
Dipnoi?        Dipnomorpha (sister of Tetrapodomorpha)
*Sphenodon*        Rhynchocephalia =3D Sphenodontida

Oh, and outside Vertebrata:
*Ginkgo biloba*        Ginkgo...phyta or whatever ending you prefer

> Aves 1758 < Avemetatarsalia 1999. 241

(Perhaps I should mention that synonyms for Avemetatarsalia, like the
misnomer Ornithosuchia, come from the early 90s if not late 80s. Does=
n't
change much about the point, however.)

> Which names have been
> associated with more clades than Mammalia, Reptilia and Aves?

Reptilia has only been associated with one clade, AFAIK, but the othe=
rs have
been attached to basically everything from panstem to crown. (Haven't=
 there
even been attempts to exclude the monotremes from Mammalia?)

> Amphibia, a total clade, is aguably one of the ten most well known =
clade
> names, being one of Linnaeus' original vertebrate classes everyone =
learns
in
> school and possessing a commonly used vernacular equivalent.

Yes. Few people know how to tell a "reptile" from an amphibian, but e=
veryone
knows both exist.

> If you argue "we could just redefine total clade names to equate to=
 other,
> more or less similar, clades", as in your Synapsida example, why no=
t do
that
> for crown clades instead*?  Sure, more people know more crown clade
> names, but they don't know they ARE crown clades and in most cases
> don't even know what a crown clade is.

I should have thought of this much, much earlier.

> I honestly never saw this as a problem.  Our language is such that =
it can
be
> assumed one means "the members of group X that can be examined for =
this
> trait have it" whenever one says "members of group X have this trai=
t".
And
> since neontologists talk about recent 'orders', 'families' and 'gen=
era' a
> LOT, to solve this "problem" would require that huge disruption in
> continuity of composition I mentioned earlier.  Is it worth it to h=
ave
> thousands of taxa removed from clades they've always been included =
in,
just
> to ensure people who are ignorant don't think genetic or behavioral=
 traits
> are known to be present in extinct stem lineages of crown clades?

Uhmm... strong words... but from my paleo-biased perspective I think =
they
fit quite well. :-)


  

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