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Re: something's wrong here: Qianosuchus phylogeny



I am now in the lab and have the pdfs of the paper and the supp. inf. in front 
of me.

Supp. inf. 4 contains the character list. All multistate characters were 
unordered -- some should have been ordered; ordering might have increased the 
resolution (though not necessarily so).

Supp. inf. 3 contains the tree. I reproduce it below, deliberately in a 
space-hogging format in order to avoid giving the impression that any terminal 
taxon might be paraphyletic to another. Keep in mind that the axis that is 
vertical in this post has no meaning whatsoever; you can rotate each subclade 
at each internode, and nothing changes. To illustrate this point, I have done a 
few such rotations. Time (not to scale) passes straight from left to right, not 
from top to bottom, not even partially. The branch lengths are entirely 
meaningless.

The point where a horizontal line meets a vertical line is meaningless because 
the vertical axis is meaningless. I've put all those points in the middle of 
the vertical lines just for aesthetics.

  ,-----------------------------------------*Hyperodapedon*
  |
--|  ,--------------------------------------*Prolacerta*
  |  |
  `--|  ,-----------------------------------*Proterosuchus*
     |  |
     |  |  ,--------------------------------*Erythrosuchus*
     `--|  |
        |  |  ,-----------------------------*Euparkeria*
        |  |  |
        `--|  |  ,--------------------------Proterochampsidae
           |  |  |
           |  |  |                       ,--Theropoda
           |  |  |                    ,--|
           `--|  |                    |  `--*Herrerasaurus*
              |  |                 ,--|
              |  |                 |  |
              |  |              ,--|  `-----Sauropodomorpha
              |  |              |  |
              |  |           ,--|  `--------Ornithischia
              `--|           |  |
                 |        ,--|  `-----------*Marasuchus*
                 |        |  |
                 |     ,--|  `--------------*Lagerpeton*
                 |     |  |
                 |  ,--|  `-----------------Pterosauria
                 |  |  |
                 |  |  `--------------------*Scleromochlus*
                 |  |
                 |  |  ,--------------------*Qianosuchus*
                 `--|  |
                    |  |--------------------Ornithosuchidae
                    |  |
                    |  |  ,-----------------Phytosauridae
                    |  |--|
                    |  |  `-----------------*Gracilisuchus*
                    `--|
                       |  ,-----------------Crocodylomorpha
                       |--|
                       |  `-----------------*Postosuchus*
                       |
                       |  ,-----------------Stagonolepididae
                       |  |
                       `--|  ,--------------*Fasolasuchus*
                          |  |
                          `--|  ,-----------*Prestosuchus*
                             |  |
                             `--|-----------*Saurosuchus*
                                |
                                `-----------*Ticinosuchus*

There is one thing that is weird about this tree, and that is the sister-group 
relationship of Phytosauridae and *Gracilisuchus*. That's all. There is nothing 
weird about the proterochampsids, for example; they are the sister-group of 
Archosauria sensu stricto as a whole.

The longest vertical line -- in its entirety -- represents the MRCA of 
Archosauria sensu stricto and Proterochampsidae.

Any questions?
-- 
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