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A Critical Re-examination of Theropod Phylogenetics
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~ =)