Re: Dinosauricon Phylogeny: in progress

["T. Michael Keesey" <mightyodinn@yahoo.com>]

--- Nick Gardner <ratites637@hotmail.com> wrote:
> I've reconstructed the trees in order to make clear what I'm talking about.
I'll just re-provide the link:
http://dino.lm.com/_temp/nodes.php

> 1. Why is _Thescelosaurus_ an iguanodontian?
> 2. Why is _Parksosaurus_ the sistergroup to _Gasparinisaura_?

Let me double-check my references, and ...

> 3. Where are _Draconyx_, _Altirhinus_, _Brachylophosaurus_, 
> _Prosaurolophus_, _Dysalotosaurus_, _Yandusaurus_, _Orodromeus_, and all 
> those other ornithopods, especially the "hypsilophodont"-grade ones...?

... as I said in my original post, _Ornithopoda_ isn't done yet.
Since basal _Ornithopoda_ have not been the subject of many analyses, I will
probably simplify the structure (big polytomies), as with basal
_Sauropodomorpha_.

> Where's _Liaoceratops_, _Styracosaurus_, and _Chaoyangsaurus_?

See original post.
 
> --Apatosaurinae
>       |--Eobrontosaurus
>       `--+--Apatosaurus
>           `--Brontosaurus
> 
> What supports _Brontosaurus_ being a separate species?

You mean genus?
I am provisionally (note that word!) using special stem-based definitions for
all genera:
(x is a species.)
Genus(x) = Clade(x <- all other species used as internal specifiers for genera)

Thus, _Brontosaurus_ would be Clade(_excelsus_ <- all other type species of
genera [including _ajax_]). The only way to invalidate it would be to show that
_excelsus_ is a synonym of a type species of an older genus (_Apatosaurus
ajax_???), or that it is ancestral to another type species.

> Why are _Neovenator_ and _Acrocanthosaurus_ not carcharodontosaurines or 
> allosaurines?

It seemed to me word was still out on which side they belonged to.
 
> Why is _Stenonychosaurus_ a separate taxon from _Troodon_?

I think there's been DML discussion on this, but it could be argued that
_Troodon_, being a tooth taxon, should be considered dubious. Dubious taxa are
simply shown as _incertae sedis_, since the designation of _nomen dubium_ is a
little subjective (or, at best, prone to change) for my tastes. (Well, so is
_incertae sedis_ -- but I kind of need that one.)

=====
=====> T. Michael Keesey <keesey@bigfoot.com>
=====> The Dinosauricon <http://dinosauricon.com>
=====> BloodySteak <http://bloodysteak.com>
=====> Instant Messenger <Ric Blayze>
=====

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