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Re: A Critical Re-examination of Theropod Phylogenetics
Your portion of the oviraptorosaur tree is similar to Lu's recent analysis,
where Avimimus was
found to be closer to other oviraptorosaurs than Caudipteryx. (however,
Incisivosaurus was the
most basal taxon in Lu's oviraptorosaur tree).
'Silly little' incomplete taxa do disrupt analyses to an extent, but i'd rather
learn of their
possible relationships in theropod evolution than seeing that Dromaeosauridae
are nestled closest
to birds for the millionth time. Your tree is informative for the
beginner/freshman in theropod
phylogenies, but is too basic to get me excited. For example this portion of
your clade below:
/---- Ceratosaurus
---------------------------------------+
\---- Abelisauridae
is very simple yet encompases 10-20 taxa spanning the Late Jurassic to the Late
Cretaceous.
Furthermore, several Abelisaurids (Abelisauroids) are known from good skull
material, so your
latter branch can be further subdivided WITHOUT the need to invoke any silly
postcranial
characters.
Many postcranial characters are quite progressive and therefore informative.
Consider the hands &
feet, as John mentioned. Howabout the cervical vertebral characters in
Naosaurids, caudal
vertebral characters in Oviraptorosaurs,
--- Nick Gardner <nick.gardner@gmail.com> wrote:
> I have become greatly distressed over the current notion of many
> theropod researchers who feel the need to dash about madly including
> multitudes of homoplastic characters, especially those of the
> postcrania, which frankly are so similiar between species, that what
> few differences there are, are little more than diagnostic characters
> for species, and not really that significant as far as phylogenetic
> relationships go. I am also distressed by their need to include
> uninformative, fragmentary, and problematic taxa. There is simply no
> need for them, they will merely distract you from finding the one true
> tree. In light of this, I have recently made some alterations to one
> such matrix I feel is truly an example of this problem. I have chosen
> to re-run the analysis from Rauhut (2000) in accordance with proper
> cladistics. Gone are the silly postcranial characters with their
> useless, homoplastic noise. Gone are the poorly known taxa such as
> Staurikosaurus, Neovenator, Coelurus, and the rest of the silly lot of
> them. What remains is a truly robust and useful analysis which should
> provide a basic framework for a hopeful return to sensible
> phylogenetics, please take note of the results.
>
> /--------------------------------------------------------- Euparkeria
> |
> | /----------------------------------------------------- Marasuchus
> | |
> | +----------------------------------------------------- Herrerasaurus
> | |
> | +----------------------------------------------------- Eoraptor
> | |
> | +----------------------------------------------------- Sauropodomorpha
> | |
> | | /---- Coelophysis
> | | /----+
> | | | \---- Syntarsus
> +---+ /---+
> | | | \--------- L liliensterni
> | | /----------------------------------+
> | | | \------------- Dilophosaurus
> | | |
> | | | /---- Ceratosaurus
> | | | /---------------------------------------+
> | | | | \---- Abelisauridae
> | | | |
> | | | | /---- Afrovenator
> | | | | |
> | \----+ | /----+---- Sinraptoridae
> | | | | |
> | | | | \---- Allosaurus
> | | | /-------------------------+
> | | | | | /---- Monolophosaurus
> | | | | \----+
> | | | | \----
> Carcharodontosauridae
> | | | |
> | \---+ | /------------------------------- Tyrannosauridae
> | | /---+ |
> | | | | | /-------------------------- Ornitholestes
> | | | | | |
> | | | | | | /---------------------- Sinosauropteryx
> | | | | | | |
> | | | \---+ | +---------------------- Compsognathus
> | | | | | |
> | | | | | | /---- Ornithomimosauris
> | | | | +---+ /----+
> | | | | | | | \---- Troodontidae
> | | | | | | /--------+
> | | | \----+ | | \--------- Aves
> | \----+ | | |
> | | | \---+ /------------- Therizinosauroidea
> | | | | |
> | | | | | /---- Avimimus
> | | | \----+ /----+
> | | | | | \---- Oviraptorosauria
> | | | \---+
> | | | \--------- Caudipteryx
> | | |
> | | \-------------------------- Dromaeosauridae
> | |
> | | /---- Torvosaurus
> | \----------------------------------+
> | \---- Baryonychidae
> |
> \--------------------------------------------------------- Ornithischia
>
> Only 569 MPTs were found despite that I had it looking for a
> ridiculously high 50,000 MPT (that silly Mickey, he suggested such a
> high, high number, I'll have it out with him over AIM later for his
> silliness), the analysis took a mere 2.44 seconds to be hashed out in
> PAUP, a jolly good nice fast time, why, I clearly won't be missing tea
> time, that's for sure. Frankly, I can't understand why more people
> wouldn't find this more practical. Fairly nice support for all those
> trees as well, ah well, I'm off for tea and crackers, cheerio.
>
> Nick Gardner
>
> P.S. When I return, I'll be off to try and reverse the same dreadful
> trend overtaking ceratopsian analyses, it's not too late, why with a
> bit of work, we'll all be back on the right track and taking our tea
> at a sensible time. Toodles~ =)
>
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