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Re: David's Statements [Extended Version]



BTW, if anyone hasn't got my complete post because it was so long and in
HTML, I can send it again in plain text and/or in several chunks. Just tell
me. Same if you can't manage the cladogram to match up.

> <The main paper begins with "When Archaeopteryx was discovered,
> birds were thought to have lots of autapomorphies, many of which
> were recognised in Archaeopteryx. But for the past 20 years or
> so, former bird autapomorphies have been 'sliding down the
> cladogram', so it has now become very difficult to diagnose a
> bird.">
>
>   This is not necessarily true: extraordinary forelimb length
> outstrips the hindlimbs; though as Mickey Mortimer has said, the
> radius in *Microvenator* is nearly equal the humerus length, the
> manus is not nearly so long and would have been less than 80%
> the hindlimb length as posited from reconstruction of the extant
> phylogenetic bracket (dromaeosaurs, oviraptorosaurs,
> *Archaeopteryx*).

Forelimb length is dependent on lifestyle and can vary fast. Just think of
us and chimps. Since the aforementioned taxa except *Archaeopteryx* didn't
fly or whatever, they all had shorter forelimbs, record AFAIK being
*Sinornithosaurus*. So I wouldn't use forelimb length in phylogeny too
often.

Well, in my paper I give two traits that IMHO are diagnostic of (Neornithes
> *Archaeopteryx*, Dromaeosauridae, Arctometatarsalia, Oviraptorosauria):
prokinesis and the carpometacarpus.

> The metatarsus is not pinched proximally, so
> the breadth of the third metatarsal either equals or exceeds
> that of the second and thirds [typo here?], altered only in
enatiornithines
> or birds whose metatarsus becomes a cannon bone.

Looks suspiciously like a plesiomorphy.

> <opisthopubic pelvis | is orthopubic in A. and Patagonykus,
> opisthopubic in dromaeosaurs [and secondarily orthopubic in U.,
> if HP Mickey Mortimer is right) => probably prone to
> convergence>
>
>   The condition of opisthopuby in dinosaurs has not been
> quantified wholly, but may be plesiomorphic in birds, as most
> maniraptorans seem to be either mesopubic or opisthopubic. You
> use the term "orthopubic" for the "strait pubes" but this may
> not be exact enough, and I prefer the term "mesopubic" to denote
> a transition between a pro and opisthopubic condition. In fact,
> based on this, one can then posit that oviraptorosaurs are
> secondarily propubic, or that the condition of the pubes
> proximally (strait up and down) occurring in tyrannosaurs, makes
> this a functional character relating to mass distribution by
> bringing the pubes between the knees neutrally, and may then
> have respiratory capabilities, then becomes convergent. The
> pelvis in *Unenlagia,* *Rahonavis,* and *Sinornithosaurus* are
> remarkably similar to one another, in the form of the ilium,
> ischia, and pubes, though the first two share the J-shaped
> lateral aspect of the pubes (hook-like pubic boot, shaft strait
> towards the distal end and not recurved). The condition of the
> pelvis in primitive birds, *Archaeopteryx* and dromaeosaurids
> are closer in the shape and form of the ilium, and form of the
> pubes as they invert caudally. I don't feel the case has been
> settled on the orientation of the pubes in the ürvogel, and can
> posit both a vertical and everted orientation with equal
> impunity.

1. Thank you for these details!
2. It's good you found out how to make äöü dots; some weeks ago someone
asked onlist how he could enter them in a search engine, and I couldn't help
him, because I'm writing on a German keybord which has keys for äöü.
Anyway -- singular Urvogel, plural Urvögel. No ü here.
3. AFAIK the case was quite sure that Archie was ortho- = mesopubic based on
the 6th and 7th specimens, has any new evidence turned up? *Patagopteryx*,
however, is mesopubic, and *Avimimus* is even propubic.

> <"In any case, Archaeopteryx was incapable of perching,
> because the halluces were too short and situated too high on the
> foot. >
>
>   This is actually the case in most primitive birds, and even
> among extant birds. But please note: perching, and perching with
> use of the hallux, are not the same thing, and length of the
> hallux does not presume perching. Galliforms, anseriforms, and
> procellariiforms, for instance, as well as gaviiforms, perch
> without using the hallux.

I'll have a look at that.

> <"Cladistic implications Archaeopteryx has no bird
> synapomorphies, and is probably nothing more than a glorified
> small flying near-dromaeosaur, '[a]nd in spite of the fact that
> dromaeosaurids are often proclaimed to be the most birdlike of
> the theropods <...>, they lack many of the theropod-avian
> synapomorphies found in other theropod families, and have too
> many specialisations to be plausible avian ancestors' (Currie,
> 1995, page 587).>
>   Curious, but which cladistic analysis has _ever_ suggested
> *Archaeopteryx* was nothing but a "glorified near-dromaeosaur,"
> but less non avian? The cladistic definition (and preferred
> non-cladistic usage) has Aves as including *Archaeopteryx.*
> Anyway, Currie's comments were about dromaeosaurids, and placing
> *Archaeopteryx* near them and then saying this suggests
> *Archaeopteryx* is therefore not a bird is very strange.

As I wrote, under current definitions, *Archaeopteryx* is an anchor for
Aves. So, under my phylogeny, either *Tyrannosaurus* is a bird, or we allow
this definition to change. "Bird" in the article refers to what is the
sister group of Oviraptorosauria in my cladogram, and this group includes
all traditional birds except *A.*. If I had said *A.* is a bird, I would
have been forced to say *T.* is one, too.

> <Considering this along with the 'theropod-avian synapomorphies'
> listed above <below> produces a cladogram <...> which differs
> >from all others in the following features: oviraptorosaurs are
> the closest relatives of birds, with which they form the taxon
> Maniraptora (conventionally defined as Neornithes >
> Ornithomimus, in Sereno [1998] defined as Oviraptor +
> Neornithes>
>
>   It should be understood that Sereno's definition is not as
> widely accepted and should not be used in the sense of priority.

I don't, just this definition exists, so someone, at least Sereno himself,
will probably use it for some time, and the rest of the sentence states that
under my phylogeny both definitions have the same content.

> Understand that Sereno's definition comes from placing
> tyrannosaurids closer to birds than are ornithomimids, and this
> is just plain ridiculous (personal opinion).

I wholeheartedly agree.

> With tyrannosaurids
> outside of the original definition by having ornithomimids being
> the stem, we get dromaeosaurids, oviraptorids, "dinobirds," and
> birds, and possibly troodontids, as being maniraptorans. This is
> the conventional, traditional, and defined content. And as
> Padian and Holtz, 1997 and Padian et al., 1999, suggest, should
> be used.
>
> <at present, these definitions do not change the contents of
> Maniraptora).>
>
>   See above, because they most certainly do.

Not under my phylogeny.

> <Maniraptora and Arctometatarsalia form Maniraptoriformes, which
> has been defined as Ornithomimus + Neornithes. The taxon with
> the definition Deinonychus + Neornithes has recently been named
> Eumaniraptora. Its name implies that it was meant to be a part
> of Maniraptora, whereas now it is vice versa -- the irony of
> cladistic definitions. I propose to name the taxon which
> includes Archaeopteryx and dromaeosaurids Archaeopterygiformes,
> which is among the oldest available names, and to define it as
> Archaeopteryx > Neornithes. Sereno (1998) has defined
> Archaeopteryx this way - that is why I consider it useless to
> define genera.>
>
>   Annoying, yes, this will probably stand as the eponymous
> Archaeopterygidae, but your usage has no priority, Sereno's does
> (unfortunately). Precisely why do you not like defining genera?
> Chris Brochu (1998) has not only defined the genus *Crocodylus*,
> but several of its species and groups of species, one of which
> is called Globidonta, and this does not reflect a "subgenus" or
> "superspecies" but a group of unique taxonomic entities (UTE's).

Works perfectly well for recent crocodiles, where we have lots of well-known
species. It doesn't work where we have one genus that is the presumed sister
group to 10,000 others. Under my phylogeny + Sereno's definitions of
*Archaeopteryx*, all dromaeosaurs are junior synonyms of *Archaeopteryx*...
Urgh, glglgl. Let's wait for the PhyloCode which will not like such
definitions.

> <But what about birds themselves? A commonly used definition is
> Aves: Archaeopteryx + Neornithes (e. g. Sereno 1998)>
>
>   Actually, this is Chiappe, 1997, then reaffirmed by Padian,
> Hutchinson, and Holtz, 1999.

OK: "used by e. g. Sereno 1998". I couldn't dig up the refs.

> <and Avialae: Neornithes > Velociraptor. In this case, Aves is
> <in terms of content> a senior synonym of Eumaniraptora and
> Avialae one of Paraves ( = Neornithes > Oviraptor [Sereno,
> 1998]), and, whether Aves or Avialae is called 'birds',
> Tyrannosaurus is a bird. >
>
>   Yeah, only if you take Sereno's definitions _and_ others'
> together. By priority classification, one doesn't get
> definitions up the yin-yang to one's own liking. One works in
> the system. Aves and Avialae have strict definitions, and so
> does Paraves,

I lack papers with cladistic definitions for dinosaur groups. I have got the
cited Sereno, 1998, and hardly anything else. I used to think that Paraves
is Sereno, 1997.

Be sure I won't write an article alone in the next few decades...

> and in Sereno's recent organization, tyrannosaurs
> are members of a group called "Aves;"

?!?

>   Priority definitions are:
>   Maniraptoriformes == { Neornithes + Ornithomimus } (Holtz,
> 1996, emended from Holtz, 1994 confused this with Maniraptora,
> which had an established definition (Gauthier, 1986) which could
> be held up)
>   Arctometatarsalia == { Ornithomimus > Neornithes } (Holtz,
> 1996, established by Holtz, 1994, and included Bullatosauria, by
> extension, but also has priority over Ornithomimoidea Sereno,
> 1999 by content, as by definition Alvarezsauridae would then be
> closer to Ornithomimus than to birds)
>   Ornithomimosauria == { (Pelecanimimus + Ornithomimus) } (I
> don't believe this taxon has been strictly defined: Sereno's
> [horribly restrictive] usage for Ornithomimidae is {
> Pelecanimimus + Ornithomimus } and by the phylogeny of Osmólska
> and Barsbold, 1994 and Perez-Moreno et al., 1994, this would
> correspond to Ornithomimosauria, which has priority by taxonomic
> foundation, and the definition shifts to Ornithomimosauria)

Sure?

>   Maniraptora == { Neornithes > Ornithomimus } (Gauthier, 1986
> defined this roughly, emended by Holtz (1994) into a strict
> definition)
>   Paraves == { Neornithes > Oviraptor } (Gauthier, 1986,
> intended as a stem, though Sereno (1998) defines it as a node;
> to include dromaeosaurids and birds, but not oviraptorosaurs and
> other maniraptorans, explicitly; thus the definition above has
> by content and usage originally priority (Padian, Hutchinson,
> and Holtz, 1999))

Odd name for a group that includes Aves. :-( .

>   Eumaniraptora == { Deinonychus + Neornithes } (Padian,
> Hutchinson, and Holtz, 1999, originally to oppose so-called
> "dinobirds" that would be paravians, but more basal (the
> original included taxa, Deinonychosauria and Avialae, do not
> include explicit generic specifiers, and it is suggestible to
> use such, but the specifiers [I really do prefer Jon Wagner's
> term "anchor," if not just because it has an _oomph_ that the
> dry "specifier" does not] are reflect this distinction, whether
> or not Troodon and Deinonychus are each other's closest taxa))
>   Deinonychosauria == either { Deinonychus > Neornithes } or {
> Deinonychus + Troodon } (Colbert and Russell, 1969, originally
> to demonstrate the raptorial similarities of the two forms,
> though not many recent phylogenies support troodont-dromaeosaur
> monophyly, so the first definition was provided to preserve the
> taxon as a useful stem opposing birds within Maniraptora;
> however, I feel the term should be kept as originally defined {
> Troodon + Deinonychus } and a new taxon [maybe] to be used for
> the first definition (like "Taxon 45, Stem 23" or something))

I agree -- because of the -sauria ending.

>   Avialae == either { Neornithes > Deinonychus } or
> {Archaeopteryx + Aves (crown birds) } (Gauthier, 1986,
> originally to define Aves as a crown-group, rather than
> including Archaeopteryx, which would follow classic usage; as
> discussed _ad nause[a]m_ on this list, classic usage is derived
> >from a non-evolutionary perspective, and Archaeopteryx is best
> used to include the concept "bird" as being relative to "Aves"
> (see below); while the first definition contains the same
> knowledge as Gauthier's usage, the original usage was not
> explicit, and could be given made more strict, and so now can
> include other taxa between Archaeopteryx and dromaeosaurids,
> such as "dinobirds")
>   Aves == {the ultimate hodgepodge} . no, I mean { Archaeopteryx
> + Neornithes } (Gauthier, 1986, as stated above, intended this
> as the crown group, but traditional usage includes tons of other
> types of "birds;" the term is broader than intended, but perhaps
> more applicable, as provided by Chiappe, 1997 (an explicit
> definition) and Padian, Hutchinson, and Holtz, 1999 (a reason
> why))
>   Metornithes == { Mononykus + Neornithes } (Perle, Chiappe, and
> Norell, 1993, which by all phylogenies except Sereno's and
> Martin's, are closer to birds anyway, and the redefining by
> Sereno for the placement of alvarezsaurs is based on strict
> ornithomimosaur synapomorphies rather than both ornithomimosaur
> and neornithine synapomorphies for an unambiguous polarity to
> see which clades with which)

Thank you for these definitions!

> <In the latter case I propose to define Avialae as Neornithes >
> Oviraptor, Ornithomimus, Velociraptor and other well-known
> non-avian theropods>
>
>   Been done, see above, you're just adding additional exclusive
> specifiers, but this doesn't resolve the definition.

It does in my phylogeny where *Tyrannosaurus* is both a member of
(Neornithes > Velociraptor) and one of (*Archaeopteryx* +
Aves/Neornithes) -- assuming that I don't want it to be a bird.

> <How would a tetanuran have swum? Undulating the tail, which
> many have suggested, was impossible - the distal half was
> stiffened - and would have been ineffective, because dinosaur
> tails were always pointed at the end instead of flattened like
> in crocodiles. Using their legs would have been ineffective,
> too, because they weren't able to sprawl and their toes were not
> webbed. There was only one other possibility - using the arms,
> which already bore wing feathers.>
>
>   Any fool animal can swim unless it bears a direct ecological
> or biological penalty. [snip]

Right. I just suppose a winged theropod would rather have used its wings for
swimming underwater (I should have included this last word for clarity)
because of their much larger surface.

> <Dromaeosaurids became secondarily "flightless". <We know this
> >from somewhere, don't we?>>
>
>   No, we assume this from the phylogenetic hypothesis of
> feathered/filamented animals and the presence of so-called
> "flight-related features" in maniraptoriforms.

This was (obviously IMHO) referring to BCF and suchlike.

> <. their hands for grasping only,>
>
>   No ability to grasp with the pollex (thumb) that does not
> oppose the second digit, and a possibly semi-mobile third
> metacarpal.

"The Mistaken Extinction" and other sources state quite clearly that
theropod thumbs were opposable to some degree.

> <Surely somewhere in the reader's head there is lurking the idea
> that Protoavis might fit this picture <...>. Protoavis is a
> problem because of its poor preservation, and it is probably a
> chimera, but it is very difficult to explain which part comes
> >from which animal. For instance, the "hand" looks much like an
> herrerasaur foot - but only the first three digits: "metacarpal
> IV" bears no phalanges, and no similar bone occurs in any known
> herrerasaur, as is the case with the "quill knobs" on
> "metacarpals II and III". There is no explanation for the
> (though unfused) furcula and the keeled sternum. Additionally,
> the chimera argument doesn't really work - if only a single bone
> attributed to Protoavis is avian, then there was a Triassic bird
> (Chatterjee, 1997).>
>
>   Huh, and then, of course, there's that idea that much of the
> material looks like it could come from a megalancosaurid. but
> don't take my word for this, take Renesto's (1999).

I didn't know this paper when mine was published, and I'm afraid I can't get
it anywhere. :.-(

> I hope, of
> course, to get down to Texas Tech to see if Sankar will let me
> view the material, some of it is actually quite fascinating from
> the scant photos and various illustrations I've seen..

Rumors have it that he hardly lets anyone see *Protoavis*... Let's hope he
lets you, because both his 1997 book and his recent 100-page article in
Palaeontographica (have yet to copy and read it) only contain drawings that
may contain slight interpretations by him...

> <"Oviraptorosaurs must also have originated at that time, but
> the fossil record keeps silent. <Not entirely true, see below.>
> They seem to have changed their diet from fish to freshwater
> snails, which were abundant in Mongolia and Liáoníng/China, and
> (like many birds later) from underwater flying to wading
> (Chirostenotes is often said to have had wading adaptations). A
> diet of mainly freshwater snails is probably the best
> explanation for their odd skulls as well for the protruding
> premaxillary teeth of Caudipteryx which might have been used in
> pulling snails out of mud.>
>
>   What mechanical or ecological (or biological) evidence does
> one suppose oviraptorosaurs ate snails? Or even *Caudipteryx*?
> Or even fish, for that matter.. Barsbold (1977), and Barsbold,
> Maryanska, and Osmólska (1990) suggest an entirely different
> mechanical proposition (clams) - these are heavily developed
> crushing jaws,
That's what I have derived from various more or less contradicting
statements on just how strong oviraptorid beaks were and from the reported
plenty of freshwater snails in oviraptorosaur-containing Gobi sediments.
Clams would fit quite well if the beak was mechanically suited to this.

> and one only needs to suck to eat a snail (sorry
> if this sounds vulgar, but I can't think of another way to state
> it).

If the snail is still alive, it isn't that easy to get it out of its shell.

> <Guide to the cladogram (shortened)
> "Ornithodira: endothermy,>
>
>   Assuming pterosaurs are more closely related to birds than to
> lizards.. Or that they're endothermic..

Assuming both.

> <insectivory,>
>
> Furthermore, the "lagosuchid" dinosauriforms have homodont,
> ziphodont jaws that appear to be carnivorous rather than insect
> eating.

Oh!
I wasn't talking of anteater-style insectivory, of course...

> <Carnosauria: nearly triangular antorbital fenestra,>
>
>   Pardon? Triangular antorbital fenestra is a very infrequent
> aspect of the hole in the head, and is directly influenced by
> the presence of the antorbital diverticulum (Witmer, 1993, 1995,
> 1997), thus may have no phylogenetic significant. The size may
> also be difficult to use, but the size of the fossa may not.
> Spinosauroids appear to be the only taxon one can reasonably
> apply this feature to, phylogenetically.
>
> <some features of hand, lower jaw, skull and pelvis according to
> Paul (1998); includes Allosauridae, Ornitholestidae, probably
> Sinraptoridae and Carcharodontosauridae. <Any comments???>>
>
>   A lot of the pectoral features (including the forelimbs) are
> also seen in coelurosaurs, to many degrees, and are avetheropod
> features; *Ornitholestes* is more likely a coelurosaur on the
> basis of several pelvic, hindlimb, and cranial features. It may
> even be closer to birds than is *Compsognathus,* with a
> ventrally concave posterior blade of the ilium, triangular
> obturator process, slender and bowed femur, and tapered fibula.
> Paul (1988a,b) does suggest the affinities of *Ornitholestes* to
> allosaurs, but there is a general dissagreement, and one can
> search the debate on the list in the archives. I'm too lazy to
> do it right now, it's already getting late. : )

HP Gregory S. Paul is onlist AFAIK... Anyway, it won't affect my phylogeny,
and I am in the long, slow process of reading all the archives, so I will
find it.

> <ornithoid eggshell (Varricchio et al., 1997)>
>
>   Pfffh . except oviraptorids, which have ratite eggshell.

Ratite eggshell is a type of ornithoid eggshell. Kenneth Carpenter: "Eggs,
Nests, and Baby Dinosaurs".

> <Oviraptorosauria: loss of maxillary and dentary teeth, skull
> boxlike and adapted to crush ?freshwater snails;>
>
>   This of course does not include caenagnathids who have more
> slicer-type jaws, or caudipterids [ugh, I _hate_ that name]
> which have pinscer-type jaws..

"skull more or less boxlike"... okay, I have confused this feature with one
of Oviraptoridae.

> <includes Oviraptoridae, Caenagnathidae, Microvenator,
> Caudipteryx and probably Protarchaeopteryx (still not completely
> prepared).>
>
>   And won't be. It's not like the animal is preserved
> Gobi-style, you can't just prep it out in that fashion; its
> squished flat like most Liaoning fossils.

Yes, I'd just love it if the sediment covering e. g. the end of the tail
would be removed so that the fossil lies on and not in the slab.

> <Dryptosauria is suggested as an alternative name for the
> group.>
>
>   Redundant, useless, Dryptosauridae has never been defined, so
> a "replacement name" is useless in any sense.

Aha.

> <Kakuru, a tibia and a toe phalanx from the Early Cretaceous of
> Australia, could be an alvarezsaurid, because it resembles the
> respective parts of Avimimus which are thought to be mononykine
> (if Avimimus is indeed a chimera <obviously not>).>
>
>   Who thinks *Avimimus* is mononykine? Mickey Mortimer puts it
> around Pygostylia, Kurzanov as a bird _sensu lato_, other
> authors around oviraptorosaurs.

Until a short time ago, lots of people thought *Avimimus* was a chimera,
consisting of oviraptorosaurian (e. g. skull), mononykine (e. g. feet) and
pygostylian (e. g. carpometacarpi) parts, and I still believed that when my
paper was published. It seemingly isn't, but it fits well somewhere below or
even above Alvarezsauria IMHO. Have yet to get the papers (and that for
*Yandangornis* which I chose to ignore in my paper because I didn't know
more about it than what The Dinosauricon says).