Re: My Phylogeny: Growing Science...

["Mickey Mortimer" <Mickey_Mortimer11@msn.com>]

These were replies to Jaime Headden's post, but Jaime said I could reply.
Thanks Jaime.

David Marjanovic wrote-

> are they just treated like question marks by PAUP*
> etc.?)

No, I've tested this and seen they give different results.  Not sure why.

> Maybe all absent interdental plates are just fused.

Maybe you're right.  Caenagnathids seem to have some remnants of interdental
plates.

> > *Avimimus* is unknown in regards to the temporal bones,
> > as they are broken and have eroded tips, and the jugal is not
> > complete, so this was indicted with a "-" to indicate missing data.
>
> So the drawing in PDW, which shows the part of the jugal that should have
> borne the ascending process as a rod, is interpretative?

Jaime puts the dorsal jugal process way far forward.  Looks ridiculous in my
opinion, like several other aspects of his Avimimus cranial reconstruction.
:-)

> character 4 -- Is a braincase known for *Caudipteryx*?

Yes, but it's crushed and broken.  I don't think any useful information can
be seen, but Jaime's drawn a reconstruction.  I'm skeptical of his drawing
to say the least...

> Do caenagnathoids really have the derived condition?

I have them coded as being primitive, but this was probably from a data
matrix.

> 4 -- Just found out I gave state 1 to ornithomimosaurs, while I don't
> actually know that. Is it true?

Yes.

> 7 -- The distal tail of *Bagaraatan* is unknown, which is enough to rule
out
> state 2, but not to distinguish between 0 and 1, which is why I gave it a
?.
> Or has this changed since Supp. 1 of Glut's Encyclopedia?

There are twenty-five caudals preserved, with at least one missing
proximally.  There were probably 35-40 caudal vertebrae in total, similar to
tyrannosaurids and ornithomimids.

> 9 -- Are segnosaurian and dromaeosaurid quadrates really double-headed?
(The
> former would fit me fine, of course...)

Dromaeosaurids (Dromaeosaurus and Velociraptor at least) have single-headed
quadrates.  Jaime apparently coded them as double-headed accidentally.  I
can't tell in Erlikosaurus, but it's usually coded as single-headed too.

>         Are quadrates from *Bambiraptor* and *Sinornithosaurus* described?

No, but they're illustrated.  Bambiraptor's is covered by the squamosal
dorsally, but Sinornithosaurus' looks to have a single head.

> 10 -- According its description (Science 1998 as *Rahona*), *Rahonavis*
> doesn't have an antitrochanter. I coded one as present in *Avimimus*,
which
> is wrong, isn't it?
>         I'm surprised to see that "enigmosaurs", ornithomimosaurs and
> tyrannosaurs have antitrochanters, too (is that why it's often coded as
> "prominent antitrochanter absent/present"?).

One of the many characters that need to be examined in more detail.
Caudipteryx, Nomingia and Chirostenotes have small, slightly developede
antitrochantors.  Segnosaurus seems to have a good-sized antitrochantor, as
might Nanshiungosaurus, though Alxasaurus' seems dorsoventrally compressed.
I'm not sure about ornithomimosaurs, none have been been illustrated well.
Gorgosaurus doesn't seem to have much of one.

> 14 -- I don't know the condition in *Yandangornis*, can someone help me?
Or
> is the paper not clear enough (the figures aren't)?

No one knows.  The distal caudals are elongate, but we have no idea how long
their prezygopophysaes were.

> 15 -- *Shuvuuia* and/or *Mononykus* have 7 sacrals. Is another sacrum
known?

The amount of sacral vertebrae in other alvarezsaurids is unknown.

> 18 -- Do we know *Avimimus* has no interdental plates?

Only the premaxillae and dentary tip have been found with "dentigerous"
margins.  The lack of teeth is associated with the lack of unfused
interdental plates as far as I know.  But it has been recently suggested
Avimimus had premaxillary teeth, which could complicate the issue.

>         The only known troodontid furcula (*Sinornithoides*) is broken in
> the middle, isn't it? Are you sure it gets 0 rather than -?
>         I  plainly forgot *Beipiaosaurus*. But its furcula is round
> ventrally (the rami don't meet at an angle), so I give it state 1, like
> *Caudipteryx* (and *Protarchaeopteryx*). (That's why I tried to avoid the
> wordings V-shaped and U-shaped -- it's )-shaped.)
>         The furcula of *Microraptor* is unknown, or is it just
undescribed?

Yes, Sinornithoides' furcula is broken, so gets a "?" for this character.
The furcula of Protarchaeopteryx may also be broken (Padian et al., 2001),
so I'm not sure how it should be coded.  That of Microraptor is unknown.

Mickey Mortimer