I think we’re now converging on a cladogram that reasonably captures the current state-of-the-art. Thank you to everyone who has contributed so far. The topology has incorporated most of the suggestions, and I think the nomenclature is finally up-to-date. As always, post something in the comments if you see anything that needs work.
The phylogeny, in general, is intended to be used for numerical analyses (e.g., phylogenetically independent contrasts) that incorporate information on the evolutionary relationships of organisms (that topic is crying out for a post, had I the time). Studies have shown that these methods are generally pretty robust, even if the phylogeny is incorrect in some details. So. . .it means that we shouldn’t sweat too much about uncertainties or the inevitable error/new data. In a handful of cases (hadrosaurs, perhaps?), we may want to run analyses with alternative trees, but we’ll worry about that when we get there. The position of some annoyingly fickle taxa (like Micropachycephalosaurus) will end up being a moot point, because we don’t have decent postcrania for them.
That said, this tree is a mutt (but a loveable one). We’ve done the best we can with the published analyses and our personal opinions. It’s pretty darned good for the most part (in my opinion), but it will never be perfect. Anyone is welcome to use it, but caveat emptor. If using the tree for other purposes, please refer to the notes given in previous posts so you have an understanding of the how’s and why’s of the tree. I am happy to send the NEXUS file to anyone who requests it (and we’ll want to include it as supplemental information when we publish).
The Current Version
The version below shows all of the taxa, with most corrections incorporated as suggested.
I’ve also generated a version where taxa that aren’t in our database are trimmed out. This is what we’ll use for most of our analyses. See below:
Notes from the previous version still apply.
Psittacosaurus xinjiangensis given as sister taxon to P. sinensis, following Sereno 1987, p. 267. This taxon, the measurements for which are based on a juvenile (Sereno 1988, original description), has not been included in any published phylogenetic analysis.
The species of Camptosaurus and Dryosaurus are placed so as to preserve monophyly for each genus.
Animantarx is given as sister to Edmontonia, following Hill et al. 2003, Figure 9
Both species of Postosuchus need to be shown
Edmontosaurus saskatchewanensis needs to be dealt with
Eoraptor needs to be added into the trimmed cladogram.
As per ongoing work by Nicolas Campione and David Evans (presented at the Frenchman Symposium and the North American Paleo Convention last year), E. saskatchwanensis is almost certainly a junior synonym to E. annectens.
For all my protestations about small details in the cladogram, its worth noting that one of the nice thing about phylogenetically-informed comparative methods is that the placement of single taxa doesn’t really make much of a difference unless they are very very different from their neighbors. So, we shouldn’t lose too much sleep over the exact phylogenetic placement of things like Lesothosaurus and Stenopelix.
A couple comments on the version 3 cladogram…. The new species of Camptosaurus is misspelled, it should be ‘aphanoecetes,’ with an ‘e’ between the ‘c’ and ‘t.’ Also, Prieto-Marquez (and probably others) have sunk Prosaurolophus blackfeetensis into P. maximus.
Just saw your note about Postosuchus. Just a quick note that Nesbitt (2009) confirmed that the two species are sister taxa.
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