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RE: Changyuraptor, new big microraptorine theropod from Early Cretaceous of China



Apparently when I first sent this out, it was truncated out of existence.  So 
now in plain text...

Jason Brougham wrote-
> Interesting. I wonder if Foth et al. examined the Balaur material in detail. 
> Characters like ossification or digit reduction, of 
> course, happen as autapomorphies in other dinosaur clades. So some of us may 
> conclude that, in fact, intensive study of the fossils, 
> rather than novelty of the results, might be objectively better.
 
First, I want to say I overestimated Foth et al.'s character inclusion.  For 
the most part they actually only include Xu et al.'s (2011) Xiaotingia matrix 
that is basically the Senter (2007) TWG matrix, and most of the characters 
added to Turner et al.'s (2012) TWG matrix that are mostly from Clark's bird 
matrix.  There's only one character from Rauhut (2003) and one modified from 
Agnolin and Novas (2011- the unenlagiine paper, not the 2013 Averaptora one 
that I was thinking of).  So this is largely Senter plus Clarke.  Given that, 
it's still FAR more extensive than Turner's, since it has Senter's added 128 
characters and includes probably ~97% of the characters Turner has plus ~14 
more taxa.  Senter also had better codings on average since Turner just used 
the original TWG Norell et al. (2001) codings for the most part.
 
But as you say, including more data is useless if it's incorrect.  So lets' 
compare the ~220 original TWG characters' codings for Balaur in Foth et al. vs. 
Turner et al..  There are a few ways codings can differ.  Here it's mostly that 
Foth et al. code a lot of characters that Turner leaves unknown- dorsal 
pneumaticity (correctly for Foth et al.), ventral sacral convexity (correctly), 
presence of a caudal transition point (correctly), proximal caudal shape 
(correctly), sternal coracoid facet orientation (correctly), preacetabular 
ventral extent (incorrectly), postacetabular divergence (incorrectly), 
proximodorsal ischial process (correctly), proximodorsal ischial scar 
(incorrectly), ischial contact (incorrectly), obturator tuber (correctly), fi
al fibular concavity (correctly), proximomedial fibular fossa depth 
(correctly), tibiotarsal intercondylar depth (correctly), cnemial crest number 
(correctly), subglenoid coracoid notch depth (correctly), and supraglenoid 
buttress presence (correctly).  There are a few times Foth et al. left Balaur 
uncoded when Turner coded it- coracoid shape (wrongly left uncoded), obturator 
process pubic contact (rightly), and obturator notch presence (rightly).  There 
are four times when Foth et al. codes Balaur correctly with a definite state 
(0, 1, etc.) but Turner miscodes it with another definite state- distal ulnar 
shape, manual ungual lips, pubic apron length, and distal humeral condyle 
orientation.  There are three times when the reverse happens and Turner has the 
correct definite coding- lacking a laterally everted glenoid, having a 
posteriorly curved pubis, and a flattened metatarsal IV.  Finally, both have 
different codings that are wrong for supracetabular crest extent, ischial 
length, 
 pubic apron placement, and pubic apron fenestration.  There are no doubt times 
both miscode it the same way, but that doesn't affect our comparison.
 
In total then, Foth et al. get 20 codings right that Turner gets wrong, and 
Turner gets 8 codings right that Foth et al. get wrong.  Seems Foth et al. did 
a better job with Balaur at least, largely due to one of my original complaints 
about Turner's study- he just leaves codable characters uncoded.  
 
Mickey Mortimer

> Date: Thu, 17 Jul 2014 00:04:01 +0000
> From: jaseb@amnh.org
> To: mickey_mortimer111@msn.com; dinosaur@usc.edu
> Subject: RE: Changyuraptor, new big microraptorine theropod from Early 
> Cretaceous of China
> 
> Interesting. I wonder if Foth et al. examined the Balaur material in detail. 
> Characters like ossification or digit reduction, of course, happen as 
> autapomorphies in other dinosaur clades. So some of us may conclude that, in 
> fact, intensive study of the fossils, rather than novelty of the results, 
> might be objectively better.
> 
> 
> _______________________________
> From: owner-DINOSAUR@usc.edu [owner-DINOSAUR@usc.edu] on behalf of Mickey 
> Mortimer [mickey_mortimer111@msn.com]
> Sent: Wednesday, July 16, 2014 7:43 PM
> To: dinosaur@usc.edu
> Subject: RE: Changyuraptor, new big microraptorine theropod from Early 
> Cretaceous of China
> 
> Jason Brougham wrote-
> 
>> I was interested to see that the new cladogram disagrees with that of the
>> recent Foth et al. Archaeopteryx paper in two important respects: It moves
>> Balaur back to the Velociraptorinae, within Dromaeosauridae, and recovers
>> the Deinonychosauria as a monophyletic clade.
> 
> That's because Han et al. just added Changyuraptor to Turner's very flawed 
> analysis ( 
> http://theropoddatabase.blogspot.com/2012/08/turner-et-al-2012-great-review-sloppy.html
>  ) which had a dromaeosaurid Balaur and monophyletic Deinonychosauria, 
> whereas Foth et al. combined Turner et al.'s data with Senter's, Rauhut's and 
> Agnolin and Novas' to form a more extensive and novel analysis.  So Foth et 
> al.'s analysis is objectively better than Turner et al.'s, though it should 
> be noted that Foth et al. seem to have not coded taxa for analyses they 
> weren't previously published in.  For instance, Turner et al. only used 
> Alxasaurus, Segnosaurus and Erlikosaurus from Therizinosauria, so Foth et al. 
> didn't code e.g. Falcarius or Beipiaosaurus for any of Turner et al.'s 
> characters, leaving them unknown.
> 
> Mickey Mortimer