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RE: Pterosaurs as basal archosauriforms



Okay, after reading the paper it turns out things are worse than I thought.  In 
short, Bennett uses an outdated analysis, unfairly eliminates most characters 
supporting avemetatarsalian pterosaurs, doesn't include the best 
candidates for non-archosaurian pterosaurs, and espouses a horrible, 
subjective cladistic philosophy.  In long- 
http://theropoddatabase.blogspot.com/2012/09/bennetts-new-paper-with-non.html

It's ironically Petersian in its defense of using few characters, using 
composite characters, and ignoring "minor" characters.

Mickey Mortimer

----------------------------------------
> Date: Mon, 24 Sep 2012 22:18:27 -0700
> From: mickey_mortimer111@msn.com
> To: dinosaur@usc.edu
> Subject: RE: Pterosaurs as basal archosauriforms
>
>
> And yet Bennett still didn't add Longisquama, Cosesaurus or Sharovipteryx, 
> despite citing Peters (2000) which argued they were key taxa for placing 
> pterosaurs outside Archosauriformes.  So Peters will justifiably say the 
> analysis is pointless, even ignoring the many suprageneric OTUs and use of 
> Lepidosauromorpha as an outgroup.
>
> I was greatly amused by-
>
> "Hone kindly sent me their Nexus files, and
> comparing them with the published data sets of Bennett (1996)
> and Peters (2000) revealed that the inability of Hone and Benton
> (2007) to replicate the analysis of Bennett (1996) was not the
> result of differences in the coding of Scleromochlus for Char. 43,
> but rather was the result of (1) four separate coding errors in retyping
> the data matrix and (2) leaving eight of the 9s that Bennett
> (1996) used to code for missing data in the matrix unchanged
> while using ? as the symbol for missing data and then including 9
> in the Symbols statement of the Nexus file so that PAUP treated 9
> as a distinct character state rather than as missing data. Similarly,
> their inability to replicate Peters' (2000) analysis of a modified
> Bennett (1996) data set was the result of seven coding errors in
> retyping Peters' published data matrix plus two 9s treated as a
> distinct character state."
>
> Coding errors due to retyping is one thing, but leaving 9 as a separate state 
> instead of unknown?  Twice?!  First I'm appalled Hone and Benton apparently 
> tried so little to determine why their versions of each matrix didn't produce 
> the same result.  Second, I'm appalled none of the peer reviewers thought to 
> check why this happened.  Surely one would notice the matrix contains both 9s 
> and ?s but otherwise only 0s, 1s and 2s.  Third it makes Hone and Benton's 
> statement below particularly ironic-
>
> "The unexpected results produced by Peters (2000) and the reanalysis here, 
> suggest that his codings should be examined more closely, particularly with 
> reference to the pterosaurs. There are numerous methodological errors 
> throughout the paper as well as errors in the interpretations of some 
> specimens and the resulting codings."
>
> Of course Hone and Benton were also the ones to leave Lepidosauromorpha as an 
> OTU in a supermatrix that also included Gephyrosaurus, Sphenodontia nd 
> Squamata (and an identical mistake with Choristodera and three choristodere 
> genera), so maybe I shouldn't be surprised.
>
> Mickey Mortimer
>
>
>
> ----------------------------------------
> > Date: Mon, 24 Sep 2012 08:37:41 -0700
> > From: bcreisler@gmail.com
> > To: dinosaur@usc.edu
> > Subject: Pterosaurs as basal archosauriforms
> >
> > From: Ben Creisler
> > bcreisler@gmail.com
> >
> > A new online paper:
> >
> >
> > S. Christopher Bennett (2012)
> > The phylogenetic position of the Pterosauria within the
> > Archosauromorpha re-examined.
> > Historical Biology (advance online publication)
> > DOI:10.1080/08912963.2012.725727
> > http://www.tandfonline.com/doi/full/10.1080/08912963.2012.725727
> >
> >
> > A previous analysis of the phylogenetic position of the Pterosauria
> > argued that pterosaurs were not closely related to dinosaurs as is
> > generally accepted, but rather were outside the crown group
> > Archosauria. However, that study was dismissed for the use of
> > inappropriate methods. Here, the data set from that analysis was
> > divided into five partitions: one with characters associated with
> > cursorial digitigrade bipedal locomotion and the other four with
> > characters from the skull and mandible, postcranial axial skeleton,
> > forelimb and hindlimb, respectively. The partitions were subjected to
> > homogeneity testing, and the Cursorial partition was found to be
> > incongruent with other partitions and all other characters at the α =
> > 0.01 probability level. Deletion of the Pterosauria removed all
> > significant incongruence, demonstrating that the incongruence results
> > from the coding of pterosaurs for the cursorial characters. The cause
> > of the incongruence was interpreted as homoplasy in hindlimb
> > morphology, and after re-evaluating and reformulating the characters
> > of the Cursorial partition, the revised data set was tested for
> > homogeneity and no significant incongruence was found. Lastly, the
> > data set was updated with additional characters and taxa from recent
> > analyses, tested as before, and when analysed suggested that the
> > Pterosauria were basal archosauriforms well outside the crown group
> > Archosauria.
>