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Re: Coelurosauria

Jamie Stearns wrote-

Among the odder things in your cladogram, I'm interested why you placed-
Bahariasaurus/Deltadromeus in Tyrannosauroidea?
It has an arctometatarsalian pes, and I had heard much about a possible relationship to Dryptosaurus as you said.

Tim pointed out Deltadromeus lacks an arctometatarsalian pes. So do Dilong and Guanlong, so it couldn't be used to place Deltadromeus so basally in Tyrannosauroidea anyway.

Dryptosaurus basal to Guanlong, Dilong and Eotyrannus?
When Arctometatarsalia was still considered a monophyletic group, Dryptosaurus was thought to be a basal member of that clade, and even before that it was thought to have some kind of relationship to the tyrannosaurs. Given that it has been known to jump around a lot in recent analyses, I felt it was safer to make it more basal.

The most recent analyses (Holtz, 2004) indicate Dryptosaurus is more derived than Eotyrannus. Dilong is more basal than both (based on its description and Holtz's unpublished results), and Guanlong is extremely basal (Xu et al., 2006).

Eotyrannus basal to Dilong?
That's what I'd always heard on the list. The two do seem to be pretty close, but I'd always seen it come up as more derived than Eotyrannus.

That's odd, because every DML post I know has Dilong more basal (including Holtz's based on his unpublished analysis). What are your references?

Ornithomimus closer to Struthiomimus than Dromiceiomimus.
From what I'd read, Dromiceiomimus had longer forelimbs and a shorter torso
than either of the other two.

Ah, but are long arms and a short torso primitive characters for ornithomimids? I would think not, but haven't checked.
Makovicky et al. (2004) synonymized Dromiceiomimus brevitertius with Ornithomimus edmontonicus, since they found Russell's proportional differences to be invalid once a larger sample was measured. Kobayashi and Barsbold (2005) found them to be sister taxa, to the exclusion of Struthiomimus.

Deinonychus outside the Velociraptor+Aves clade?
Larger size (everything seems to get smallr that farther one goes into Dromaeosauridae) and deeper skull than Velociraptor and Saurornitholestes, and last I heard, Bambiraptor had also been reconstructed with a long, low skull.

Yet Dromaeosaurus and Adasaurus are similar in size to Velociraptor, smaller than Deinonychus. And troodontids and unenlagiines are small too.
Compared to skull height, Bambiraptor has a snout comparable to Atrociraptor and Achillobator in length, but it is a juvenile, which may affect things. While Deinonychus has a longer snout than Saurornitholestes, Bambiraptor, Sinornithosaurus and Archaeopteryx. Also notable is that Buitreraptor has a very long snout, while most basal birds have short snouts.
As for snout height, it depends where you measure it. Anteriorly, Bambiraptor has a taller snout than other dromaeosaurs. Posteriorly, you're right that Dromaeosaurus and Deinonychus have tall snouts. But troodontids and Buitreraptor don't have tall snouts, so maybe having a low snout is primitive.
The moral is "know your outgroup".

Achillobator as the most basal of the dromaeosaur+Aves clade?
It's often been mentioned that it has a strange combination of primitive and advanced features, and it came up as pretty basal in most of the analyses I'd seen.

But you have troodontids and unenlagiines as the closest relatives to dromaeosaurs+birds. And Achillobator's 'primitive characters' (propubic pelivis; proximally placed obturator process; short coracoid; etc.) aren't seen in troodontids or unenlagiines. So again the lesson is polarity (which state of a character is primitive for the group). If you had dromaeosaurs related to carnosaurs, you might expect a dromaeosaur like Achillobator to be the most basal one. But if dromaeosaurs are related to troodontids and unenlagiines, wouldn't it make more sense for the dromaeosaurs most similar to Sinovenator, Mei or Rahonavis to be most basal?

Mickey Mortimer