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Re: Revised *classification* of Aves



Ken Kinman (kinman@hotmail.com) wrote:

<As a followup to my earlier posting this morning, I present below my 
updated classification of Class AVES sensu lato. It is an apomorphy-based
taxon that is *approximately* equivalent to Sereno's "Maniraptora" (but he
excluded Mononykiformes).>

  It's Gauthier's (1986) Maniraptora, defined as all taxa closer to birds
than to *Ornithomimus* (Holtz, 1996), or using Sereno's definition, the
MRCA of *Oviraptor* and Neornithes. They presently correspond to the same
group, except that under Holtz' (priority) definition, *Coelurus* and a
few other taxa that do not meet Sereno's definition may also be
maniraptorans.

<It is more restricted than the official stem-based Maniraptora (which
probably includes segnosaurians, Coelurus, and Alvarezsaurus).>

  And because of this, it's wrong, right?

<And since most birds do not "manuraptor" their food, it is certainly a
totally inappropriate name for the entire Class anyway.>

It doesn't matter if birds manirape (whatever that is): the name refers to
the adaptations of the wrist, which Pygostylia dervived into the fused
wrist and non-raptorial manus, reduction of the third digit, and reduction
of the opposability in the first digit. This is diagnostic of Pygostylia,
however, irrelevant of Maniraptora's base constituency. The same vice
versa: it doesn't matter that a stem derives the condition and no longer
is able to snatch with the hands ... this is quibbling over problems of
finding reversals in an apomorphy based system where "all taxa must have
this feature or fail to become this group", which is what most people seem
to be noting on this list about Feduccia (and Martin and fellows who
adhere to their philosophy) and Ken's phylogenies.

<What was once called Aves is virtually identical to the cladistic Avialae
(which begins at Rahonavis or Archaeopterygidae; i.e. node 6 or 7 in Order
Archaeopterygiformes below).>

  Actually, it generally begins at *Unenlagia* (Novas and Puerta, 1997),
and was originally used to include Neornithes + *Archaeopteryx* by
Gauthier, 1986, but was redefined phylogenetically (Gauthier did not
explicitly state his definition) by Padian (1997) as all taxa closer to
Neornithes than *Deinonychus*

  Holtz, T.R., Jr. 1996. Phylogenetic taxonomy of the Coelurosauria
(Dinosauria: Theropoda). _Journal of Paleontology_ 70: 536-538. [note
regarding Holtz, 1995, where Holtz defined Gauthier's Maniraptora to what
is now Maniraptoriformes]
  Gauthier, J.A. 1986. Saurischian monophyly and the origin of birds.
_Memoires of the California Academy of Sciences_ 8: 1-55.
  Novas, F.E. & Puerta, P.F. 1997. New evidence concerning avian origins
from the Late Cretaceous of Patagonia. _Nature_ 387: 390-392.
  Padian, K. 1997. Avialae. pg. 39-40 in Currie and Padian (eds.)
_Encyclopedia of Dinosaurs_ (Academic Press [New York]).

<Plesion Alvarezsaurus is joining segnosauria as being preliminarily
ejected from Class Aves.  If there is any really good evidence that it 
belongs in Class Aves, I would like to hear of it.  Alvarezsaurus appears
to be an ornithomime-segnosaurian "grade" form, along with Coelurus.>

  Yeah, all that evidence involves it being considerate to mononykes in
elongated mid to distal caudals, procoelous caudals, retroverted pubis,
postacetabular ala of ilium recurved ventrally. Problematically, the known
material is insufficient to account for the general phylogenetics, but
they do allow it to be placed outside of all other mononyke taxa; these
include the condition of the caudals, form of the coracoid, shape of the
ilium, details of the distal femur and the rest of the hindlimb material,
including the tarsus, that show it is a "mononyke" and that it is the most
basal known member. No one doubted this more than Chiappe, who explicitly
tested it from 1996 to the present in cladistic analysis, and in general
where it is a defacto bird as a result of placement with *Mononykus* under
the Metornithes hypothesis (*Mononykus* + Neornithes). Under Sereno's
hypothesis of a Ornithomimoidea (*Mononykus* + *Ornithomimus*),
Metornithes is a junior synonym of Maniraptoriformes (*Ornithomimus* +
Neornithes). This has all been detailed on the list before, including
specific comments on *Alvarezsaurus;* it might be wise to review them as
they include more detailed listing of synapomorphies. You enjoy Mortimer's
analyses enough, you may be pleased to hear that he participate well in
that discussion, as did Buchholz and others.

  Oh, BTW, *Parvicursor* is most certainly a mononyke, irrelevant of Karhu
and Rautian's naming of them in separate "families". Nothing about
*Parvicursor* makes this taxon any more different from *Shuvuuia* than it
is from *Mononykus*, implicit in the argument that all three are in the
same monophyletic group separate from *Patagonykus.* You have also coined
Patagonykidae, as this was never Chiappe's (1996, 1997) intention. The
phylogeny as supported by analysis from 1993 to 2001 is:

--Alvarezsauria Bonaparte, 1993
  |--Alvarezsaurus Bonaparte, 1993
  `--+--Patagonykus Chiappe, 1996
     `--+--Parvicursor Karhu and Rautian, 1996
        |--Mononykus Perle, Chiappe, and Norell, 1993
        `--Shuvuuia Chiappe, Clark, and Norell, 1998

  There are also further material from South America, North America, and
elsewhere which corresponds to the mononyke groups. Plus some other stuff
... but as this stuff is in press now, no more talkie...
 
<3  Mononykiformes Kinman, 1994>

  Still doesn't beat Bonaparte, 1993... sorry. Besides, Alvarezsauria has
been phylogenetically defined and is used in such a manner in all
phylogenies except Sereno's: all taxa closer to *Mononykus* than to
Neornithes.

  I have also decided that because Anseriformes include animals which are
_not_ geese (Lat., _anser_) I will rename the suborder
"Ansericygnanatiformes". But because it must also encompass screamers,
this name may then exclude them, and they must be a plesion at the base of
subclass Neognathae. Now to tackle the other bird names which don't make 
sense....

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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