[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

My Phylogeny: Growing Science...



>   I personally feel you need to work on how your characters are phrased.
> I've added a character that clarifies information on what the parasphenoid
> capsule is in ornithomimosaurs and troodontids; they are not the same
> thing, exactly, and the inflated basisphenoid, shared by both,m
> is a more broadly-expressed feature that is related.

Thank you a lot! Slowly I begin to understand...

> The addition of the sickle-claw character may also be of use.

I have already thought about that. But this character is complex.
Dromaeosauridae, *Sinornithosaurus*, *Bambiraptor*, *Microraptor*,
*Rahonavis* and *Troodontidae* have the classic sickle claw. In
*Archaeopteryx* the mt and toe are shortened, and the toe is usually
regarded as hyperextendable, but the claw is not enlarged. In *Yandangornis*
the toe looks like in Archie, but I at least don't know whether it is
hyperextendable. In Confuciusornithidae at least the claw is enlarged, but
said not to be hyperextendable. There have also been rumors about
*Ornitholestes* having something... but I haven't added it anyway (yet).

> Look at features that consider various relationships. This matrix appears
> to be focused on finding bird outgroups, but one might want to get
> general in light of troodontids, etc.

sure

> To remove polymorphisms, split the taxa. You can probably use
> *Pelecanimimus*, *Garudimimus*, and
> Ornithomimidae as separate otu's, and one might want to code
> *Beipiaosaurus* separately from
> Therizinosauroidea.

Definitely a good idea. I'm just too lazy to hunt up the papers at the
moment :-) , and I try to avoid having inapplicable characters (but maybe
that's unnecessary; are they just treated like question marks by PAUP*
etc.?)

>  I also added a state to the interdental plate character, qualifying the
> absence of these in some birds, *Avimimus*, oviraptorosaurs,
> ornithomimosaurs (unknown in *Pelecanimimus*), and troodontids.

Maybe all absent interdental plates are just fused. The *Eotyrannus* paper
says *E.* and troodontids have "small pointed interdental plates" (therefore
I tried to add it to have a potential arctometatarsalian synapomorphy...
unglorious move considering my little knowledge).

> *Avimimus* and Alvarezsauria share the "hyper" arctometatarsus, where the
> third mt is completely contained within the midshaft of the cannon,
> between mt's II and IV, as in *Parvicursor*;
> *Patagonykus* is described as having a broad mtIII, but it has been my
> feeling based on the proximal morphology of this element that this is not
> mtIII at all, but conjoined mt's II and III.
> The coding was altered to affect this.

But *Alvarezsaurus* has the _primitive_ condition (state 0 or maybe 1
according to the illustration in Glut's Encyclopedia p. 119; the diagnosis
says "III comparatively narrow as seen from behind", so maybe 1 is better).
BTW, its mt II is shorter than IV, but the toe is not, possibly farther
complexing the sickle claw character.

> You left out a coding for dromaeosaurids, I added it back in.

True. Thanks! :-)

> I also added and coded *Microraptor* for you.

I knew something was missing :-)
Just had a look at the paper, it really has a "normal" arctometatarsus, as
you coded it. Strange IMHO.

> As of right now, I have over 300 characters
> coding for relationships among and outgroups to oviraptorosaurs. Your
> matrix is broader in
> perspective, so you may wish to sit down and think abotu these a little.

Erm, sure...

> *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?

> All worrisome and uncoded
> characters (I need to check up on them) are "?".

Are ? and - treated differently by PAUP* and such programs?

> Compsognathidae 000-0 000-0 00000 00--0 0000
> *Bagaraatan* 1---- -1--0 1-00- 0---- ----
> Tyrannosauroidea 00012 01001 00100 01000 1000
> Ornithomimosauria 00012 01001 00101 01--1 1000
> Troodontidae 00012 01000 10111 00201 1001
> Segnosauria 00010 11-11 00221 10100 1000
> Oviraptoridae 00110 11011 00221 10200 1000
> Caenagnathidae 00112 110-1 00221 102-0 -000
> *Caudipteryx* 00?11 12011 00220 00200 -000
> *Nomingia* 000-- 121-1 00221 1---- ----
> Dromaeosauridae 00100 01011 (01)0010 01000 0001
> *Bambiraptor* 000-1 0100? 00-1- 00010 --01
> *Sinornithosaurus* 000-1 01001 00110 00010 0-01
> *Archaeopteryx* 00001 02000 00210 00-00 0-00
> *Rahonavis* 101-0 0-0-1 11111 0---- ---1
> *Microraptor* 1---2 01--- 00110 0020- ---1
> *Avimimus* 100?3 ---?1 10--1 -02-0 0--0
> Alvarezsauridae 111-3 11011 11220 101-0 0100
> Yandangornis ----1 12--- 1-2-- ----- ----
> Pygostylia 11111 12111 11221 10(12)10 0(01)10

Just asking (I want to learn something from the whole affair at least :-) )
character 4 -- Is a braincase known for *Caudipteryx*?
3 -- The *Rahonavis* paper says troodontids, like *Unenlagia*,
*Archaeopteryx*, *Rahona[vis]* and Metornithes, have "contact lost between
distal ischia". Has that been revised?
Do caenagnathoids really have the derived condition?
4 -- Just found out I gave state 1 to ornithomimosaurs, while I don't
actually know that. Is it true?
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?
8 -- I'm serious about ? in *Caudipteryx* (see discussions from June) and -
in Alvarezsauridae (still no tail end known). Is any caenagnathid tail end
known?
9 -- Are segnosaurian and dromaeosaurid quadrates really double-headed? (The
former would fit me fine, of course...)
        Are quadrates from *Bambiraptor* and *Sinornithosaurus* described?
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"?).
11 -- According to the same paper troodontids don't have an undivided
trochanteric crest. Has that turned out to be wrong?
14 -- I don't know the condition in *Yandangornis*, can someone help me? Or
is the paper not clear enough (the figures aren't)?
15 -- *Shuvuuia* and/or *Mononykus* have 7 sacrals. Is another sacrum known?
17 -- Why 1 for Dromaeosauridae?
18 -- Do we know *Avimimus* has no interdental plates?
19 -- Tyrannosaurid furculae (*Gorgosaurus*, *Albertosaurus*,
*Daspletosaurus* at least) are more U- than V-shaped and definitely get
state 1, as shown in the famous paper
        Peter J. Makovicky & Philip J. Currie: The presence of a furcula in
tyrannosaurid theropods, and its phylogenetic and functional implications,
JVP 18(1), 143 -- 149, March 1998
        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?
        *Archaeopteryx* and Oviraptoridae have to get state 1. Their
furculae are as U-shaped as that of *Confuciusornis*.
22 -- ? rather than - in *Bambiraptor*, AFAIK, if that matters.
23 -- I coded that wrong, it's a polymorphism in Pygostylia. *Shuvuuia* at
least gets state 1 (the jugal and the caudal half of the maxilla are just a
rod).