Message 2004-10-0187: short combined answer

Wed, 20 Oct 2004 00:11:40 +0200

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Date: Wed, 20 Oct 2004 00:11:40 +0200
From: [unknown]
To: PML <>
Subject: short combined answer

----- Original Message -----
=46rom: "Philip Cantino" <>
Sent: Monday, October 18, 2004 1:56 PM
Subject: Fwd: Re: use of vernacular names

> >We'll see if "mice" will be applied to Myodonta, Muroidea,
> >Muridae, Murinae or *Mus*, we'll see if "birds" will be applied
> >to Aves, Avialae, Pygostylia, Avipinna, Maniraptora or whatever

I made a mistake in my thinking here. If Aves will be applied to the
crown-group, it will be quite far apart (by the number of internodes)=
the cluster of the others, and we would have all the confusion severa=
people have now warned about with the tetrapod example; this is becau=
"aves" means "birds", systematists know this, and even more people ar=
e used
to calling "birds" Aves.

> The name that led me into this line of thinking was "seed plants".
> In Paris, Michael Donoghue and I defined Spermatophyta as applying =
> the crown clade of seed plants, but it is often used for the total
> clade.  As I anticipate the likely negative reaction of some of my
> colleagues to our proposal, my hope is that they will not object so
> strongly if Pan-Spermatophytes such as the Paleozoic seed ferns can
> still be referred to as "seed plants".  If we want to introduce
> greater precision into their use of the vernacular name, we can use
> the terms crown seed plants and stem seed plants, but both are seed
> plants.

Except that some stem seed plants lack seeds and will therefore likel=
y not
be called seed plants. This is exacerbated by the fact that Spermatop=
literally means "seed plants", which systematists know.
        But we will see how well the prefix "stem " will be accepted =
in the
systematic community. What I just wrote above might therefore not mat=
ter. I
just have to add that I can't quite imagine how to translate this pre=
into German. Stammsamenpflanzen? Seed plants with a tree trunk? Hm. :=
Worse yet, it has already been in use for a different concept, that o=
rhizome taxa. In German as well, "Cotylosauria" were the "stem reptil=
es", th
e multiply paraphyletic assemblage of basal amniotes from which synap=
diapsids, turtles and so on _somehow_ derived, in ways about which no=
cared. You know, the precladistic phylogenetic trees that were compos=
ed of

----- Original Message -----
=46rom: "Philip Cantino" <>
Sent: Tuesday, October 19, 2004 2:35 PM
Subject: applying widely known names to crown clades

> Jason Anderson wrote:
> >Thus, as I asked in my first email and ask again now,
> >why are we persisting on keeping Tetrapoda attached to the crown, =
and use
> >Holotetrapoda for the apomorphy-based definition, when using Tetra=
> >Neotetrapoda (or whatever) is logically just as consistent, but
> >additionally, will maintain consistency with the literature, and m=
> >might help to bring more workers onside?
> [...] I am less interested in the
> applications of particular names than I am in developing a system
> whose consistency will (1) help users to understand and remember th=
> phylogenetic meanings of names and (2) convey a limited amount of
> phylogenetic information directly in the name (e.g., that Pan-X is
> the total clade corresponding to crown clade X).

I support the autonym proposal.
An otherwise consistent system, however, risks steamrolling perhaps h=
alf of
all ivory towers that contain one systematic community that researche=
s one
particular part of the tree. The definitions of names should rather b=
decided on a case-to-case basis, to ensure that the PhyloCode will ha=
enough supporters.

> There are other conventions that would also offer such advantages.
> For example, widely used names that refer to a character (e.g.,
> Tetrapoda) could be applied consistently to  apomorphy-based clades=
> with Neo- and Pan- referring to the corresponding crown and total
> groups, respectively.  However, from a practical standpoint, this
> convention would not work as well.

I agree. In my opinion Tetrapoda should get an apomorphy-based defini=
(at least for now) not because of the name itself, but because it is
practically always equated to the origin of digits, which in turn see=
m to be
either clearly present or clearly absent because of their development=
genetics. The turtles are another such case -- the shoulder blades ar=
either outside or inside the ribcage. Now, at midnight, I can't think=
more, but there may be a dozen among invertebrates.
        (I find Walter Joyce's decision to use *Testudinata* for the
apomorphy-based and *Testudines* for the crown clade salomonic.
Unfortunately such couples synonyms are not always available.)

> Another option would be to apply widely known names consistently to
> total groups, with Neo- referring to the corresponding crown, but
> this would present a different problem.

Ironically, at least one pure* neontologist (Prof. Peter Ax) has advo=
applying _all_ names to their total groups. It is a very bad idea, ho=
in terms of Rec. 10A.

* So pure that he refuses to name any clade of entirely extinct anima=

> I agree with Jason that an apomorphy-based application may be most
> consistent with traditional usage of certain well known names, but =
> place higher priority on the advantages of consistency in applicati=
> of widely used names.  Because applying such names consistently to
> crown clades does not have the practical problems that applying the=
> consistently to apomorphy-based or total clades would have, I favor
> the former.

In a considerable number of cases this convention has the same proble=
ms as
the total clade convention would have.


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