Re: Philidor: No Class (long)

["David Marjanovic" <david.marjanovic@gmx.at>]

----- Original Message -----
From: "Williams, Tim" <TiJaWi@agron.iastate.edu>
Sent: Monday, August 26, 2002 11:15 PM

> > Now dinos are at a level with birds and reptiles.
>
> They are?  News to me.  I'm aware that Bakker proposed a "Class
> Dinosauria" nearly twenty years ago.
>  Like the A-Team and the Rubik's Cube, the idea
> caught on briefly, but I don't see anyone pushing it any more.

Usual in Linnean system:

Class Mammalia
Class Reptilia
  Subclass Synapsida (paraphyletic)
  Subclass Anapsida
      Order Testudinata
  Subclass Diapsida (p.)
    Superorder Archosauria (p.)
      Order Saurischia (p.)
        Suborder Theropoda (p.)
          and so on (p.)
Class Aves

Bakker & Galton 1974 AFAIK... never really catched on, because by the time
most dinosaurologists would have accepted it, they already preferred
phylogenetic nomenclature:
Class Mammalia
Class Reptilia
  Subclass Synapsida (or just Pelycosauria?) (p.)
  Subclass Anapsida
      Order Testudinata
  Subclass Diapsida (p.)
    Superorder Archosauria (p.)
Class Dinosauria
  Subclass Saurischia (p.)
    ?Order? Theropoda (p.)
    and so on (p.)
  Subclass Aves

Phylogenetic _nomenclature_ (_examples_, several of them invented right now,
the rest simplified! Please don't cite these!!!):
Amniota = {*Rattus* + *Passer*}
Anapsida = {*Testudo* > *Passer*}
Archosauria = {*Crocodylus* + *Passer*}
Diapsida = {diapsid condition in *Crocodylus*}
Dinosauria = {*Passer* + *Triceratops*}
Mammalia = {*Sinoconodon* + *Rattus*}
Saurischia = {*Passer* > *Triceratops*}
Sauropsida = {*Passer* > *Rattus*}
Testudinata = {*Testudo* > *Pareiasaurus*}
Theropoda = {*Passer* > *Saltasaurus*}
Theropsida = {*Rattus* > *Passer*}

Example for a phylogenetic classification = a cladogram with applied
phylogenetic nomenclature:

--Amniota
    |--Theropsida
    |    `--Mammalia
    `--Sauropsida
         |--Anapsida
         |    `--Testudinata
         `--Diapsida
              `--Archosauria
                 `--Dinosauria
                    `--Saurischia
                       `--Theropoda
                          `--Aves

> > Problem is sentiment; why, do you know there are actually people who
> > want to classify birds under dinos, diminishing birds as a group, in
> > order to demand recognition that dinos have descendants?!

Bakker did "diminish birds as a group". But who has ever complained that
bats, with all their marvelous flying diversity, are likewise "diminished as
a group" by being included in Mammalia?
        Under phylogenetic nomenclature, there are no ranks, and therefore
no diminishing or anything else. Phylogenetic nomenclature simply takes the
tree of life as it is thought to be and binds labels to it. That's it. See
above.
        Because of the way the definitions look, the content of every clade
is therefore subject to change when our knowledge increases. That's the way
it should be anyway IMHO. An advantage over the Linnean system is that
_only_ disagreements over phylogeny can produce disagreements over
classification. Ranks, in contrast, are not based on anything observable,
and neither are decisions on which paraphyletic groups to name at the
expense of which holophyletic ones.

> The problem is not "sentiment".  And it isn't a "problem".  Evolution put
> birds *within* the dinosaurs, and any taxonomy that aims to reflect the
> evolutionary history of a clade requires that this relationship be
> recognized.

Apparently HP philidor11 doubts that evolutionary history _should_ be
reflected in classifications. Correct? IMHO evolutionary history is the one
obvious thing that can be reflected in a classification, so why shouldn't
classifications be made that way, especially considering that "nothing makes
sense in biology, except in the light of evolution".

> > Science doesn't work as sentiment.  Popularly and scientifically,
> > you've got your reptiles, you've got your birds, you've got your
> > dinos.

And you've got your vertebrates. But reptiles, birds and dinos are vertebrat
es. So why shouldn't birds be dinos? And have you got your reptiles either
scientifically or popularly?

> > Pure logic and clear definitions always win out.

Phylogenetic nomenclature www.phylocode.org will be pure logic and clear
definitions. No?

> > The glance of the traveler on horseback is, as Jefferson said, the
> > exemplar of scientific classification at work.
>
> The honorable Jefferson must have been drunk when he said that.  Or high.

I'm pretty sure he was neither. He just said that long before Darwin
published. That's it. Jefferson thought that living beings and minerals
alike were _stamps_ that everyone could classify as they liked, _be it by
color_, and that Linné's classification, whereby he probably meant the exact
pattern, e. g. that he put *Rhinoceros* into Order Glires, was the most
BEAUTIFUL that had been _invented_ so far. And because Jefferson's
contemporaries used Linné's exact system (or so it seems from Jefferson's
quote), Jefferson thought it should never be changed, and *Rhinoceros*
should stay in Order Glires forever.
        Today, on the other hand, we know that living beings don't float
around discretely and unconnected like stamps or chess openings. Instead,
they form part of the tree of life, so there is an, if you will, NATURAL way
to classify them: by phylogeny. So why shouldn't we try to do it that way.
We have found something interesting to talk about, evolution, which has
produced the diversity we try to classify, with all the features we can see
from horseback or with the gene sequencing machine. Therefore our
nomenclature system should make it as easy as possible for us to talk about
evolution. Nothing that's better for that purpose than phylogenetic
nomenclature has been invented so far. Therefore let's use it.

Regarding Monsieur Philidor... today he could show off with being a chess
master, and people would love him for it, like they love Kasparov (and hate
Deep Blue :-) ), without having any idea of Philidor's or any defense.