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coelurosaurs and phylogeny type stuff


 5. There's always "Ginnareemimus", the Thai ornithomimosaur without an
 arctometatarsus. But I would leave ornithomimosaurs "2" until its identity
 is ascertained.

Does it really lack the condition? 

...and also, is it really ornithomimid?


Then *Ornitholestes* (I counted 43 in Glut's Encyclopedia p. 644) comes in,
and I have, should I use *Allosaurus* as an outgroup, a synapomorphy of
Coelurosauria excluding Compsognathidae. Rather uninformative as long as I
have no outgroup.

Horse's mouth... check out Osborn's original description of the animal (lamentably, as incomplete as it is, it is the best thing ever published on Ornitholestes). People tend to copy his figures and the dotted lines become solid, and people copy the copies... many of the bones illustrated never actually existed. We don't have any idea how many vertebrae are in the tail of Ornitholestes. One could probably take the same tail and draw it with anything from 30-50 vertebrae, and if one had the artistic ability make it look good, plausible, even convincing. Harass the nearest museum until they let you start looking at real specimens; nothing beats seeing real bone to understand the difficulty and ambiguity of phylogenetics. Differences others have overlooked will appear; supposed differences will often turn out to be problem of interpretation, or just downright inaccurate. Some of the stupid errors I see in other people's matrices make me want to scream- and anyone who looks at my matrix with some knowledge of the material will likely feel the same. I wanted to club myself over the head after I got a good look at an uncrushed caenagnathid femur and realized that while I was correctly grouping the femoral heads according to their morphologies, I was *completely* wrong on the homologies (disregard anything I've said about femoral homologies in the past year...). On the other hand, some of the stuff I've seen has convinced me that other people have some things backwards. $*%^(*&(^, I saw *interdental plates* in Saurosuchus galilei, and Coelophysis-style epipophyses in a plateosaur. Those are not supposed to be there, so what does this imply... then a lot of people regard the kinked snout of coelophysoids as a derived character but really a subnarial gap and associated dentary fang is in all kinds of archosaurs, even crocs, so shouldn't it be primitive. Eoraptor has this too. We're stumbling towards consensus with the Theropoda, but how much can we take for granted now. Only a few years ago, therizinosaurs were regarded as some kind of basal saurischian or ornithischian by people like Gauthier and Sereno... Alvarezsaurs are jumping all over the damn place because they're so derived (I don't for a minute buy that they're ornithomimids though). Incidentally, basal alvarezsaurs are our friends- being less transformed they provide a sort of "missing link" to help draw the derived alvarezsaurs out next to... well, duckbilled platypi or whatever alvarezsaurs ultimately turn out to be related to. That's another key, more taxa is better than more characters, generally. Seems to me, the real switch in thinking on alvarezsaurids was partly as a result of the basal alvarezsaurids looking more like traditional coelurosaurs, and partly as a result of intermediate birds like Confuciusornis, which didn't have a huge sternal keel or incomplete postorbital bar.
Interpretation takes artistry and effort, but at the end of the day maybe I'm better off saying, "screw this, I can't figure out anything more from this skeleton, lets go grab a beer" than working too hard and seeing something that isn't there or making a mistake. A large data set can drown out mistakes, however so many of our taxa can only be coded for a handful of characters, so maybe we're better of with 100 characters you're dead certain about than 400 we're feeling a bit unsure about? I'd much rather have ten characters correctly coded for a bashed-up specimen like the Sinosauropteryx type than twenty, with five of them miscodes and potentially misleading me... I tend to get rid of a lot of characters too, if I either am not qualified to code them correctly or I think the differences don't reflect real, obvious differences in the skeleton. On the other hand, even if I have a character which I regard as phylogenetically useless, but it's easy to code (premaxillary teeth serrated vs. unserrated, e.g.) I throw it in. That's another thing- certain workers with abnormally high consistency indices say they can ignore homoplastic characters when making their data matrices. Seems to me this is circular, since how do I know what's homoplastic until I've thrown everything into the mix and run the matrix? Maybe what I think is signal is actually homoplasy and vice versa? Is real phylogenetic signal like pornography- you know it when you see it? Or like pornography in the sense that it's difficult to see because it's often scrambled?
Regarding Avimimus- there is a bit more to them than just Avimimus (I'd say more but should be something on this at SVP from Michael Ryan). Some ?Avimimidae I've seen is hard to interpret, since the ankle is so heavily fused, but it may have a complete third metatarsal in there somewhere. Also, Russell says there's one Dromiceiomimus out there which apparently lacks the third metatarsal proximally (or is the darn thing a Dromiceiomimus then?), so I try to be careful about putting too much weight on its form.
Anyways, keep at it. Mickey's done some pretty impressive stuff, better than some of the published things I've seen. I think he may be onto something with Bagaraatan, maybe it's a very derived theropod which has done something really weird to its tail.

incidentally- Patagonykus may not be too big to be a myrmecophage. Consider that aardvarks get over 100 lbs. Giant armadillos, sloth bears, giant anteaters, pangolins and aardwolves are all relatively large. In fact, the average myrmecophage is quite large when you consider that the majority of mammals are tiny mouse- and rat-sized things.

-N