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Benton et al.'s Supertree



Thanks to whoever pointed out the new dinosaurian supertree page at
        http://palaeo.gly.bris.ac.uk/dinosaur/supertree.html

For anyone who's not bothered to look at it yet, treat yourself:
there's a PDF of the paper itself (five pages) which is an interesting
read.

One interesting section concerns the phylogenetic conclusions:

        Contentious issues in dinosaur systematics are resolved in the
        present supertree.

        Sauropodomorpha is composed of Saturnalia and monophyletic
        Prosauropoda and Sauropoda (Sereno 1999; Benton et al. 2000;
        contra Gauthier 1986).  Within Prosauropoda, a monophyletic
        Melanorosauridae (Riojasaurus, Camelotia and Melanorosaurus)
        emerges as the sister group of Plateosauria (Massospondylus,
        Yunnanosaurus and Plateosauridae).  Within Sauropoda,
        Barapasaurus is the sister group to all other Eusauropoda
        (Upchurch 1998; contra Wilson & Sereno 1998) and Omeisaurus is
        more closely related to Neosauropoda than it is to Shunosaurus
        (Wilson & Sereno 1998; contra Upchurch 1998).

        The early dinosaurs Eoraptor and the Herrerasauridae are basal
        theropods (Sereno et al. 1993; contra Langer et al. 1999).
        Ceratosauria is a monophyletic group containing Coelophysoidea
        and Neoceratosauria (Sereno 1999; Holtz 2000; contra Forster
        1999), while torvosaurids are more closely related to derived
        tetanurans (Avetheropoda) than to spinosaurids (Holtz 2000;
        contra Sereno et al. 1994).  Therizinosauroidea is the sister
        group of Oviraptorosauria (Russell & Dong 1993; Holtz 2000;
        contra Sereno 1999), but Caudipteryx is a basal member of
        Paraves: it is excluded from both Oviraptorosauria (contra
        Sereno 1999) and Avialae (contra Ji et al. 1998), while
        Metornithes is monophyletic and contains Ornithothoraces,
        Avimimus (Chatterjee 1991; contra Holtz 1994) and
        Alvarezsauridae (Chiappe et al. 1996; contra Sereno 1999).

So mostly, these seem to be pretty much the standard interpretations,
with the exception maybe of megalosaurs being closer to tetanurans
than to spinosaurs; but then I guess you'd expect a tree which is
essentially a synthesis of existing ones to reflect their consensus.

The introductory page comments further:

        There is a running debate about the place of birds in the
        scheme of things. Our supertree shows once and for all (as if
        there was still any doubt) that birds are dinosaurus, very
        close to the dromaeosaurids like _Deinonychus_ and
        _Velociraptor_, and to the troodontids like
        _Saurornithoides_. It would take a huge amount of
        counter-evidence to break up this part of the tree, so the
        anti-dinosaur-bird people have clearly lost the debate.

(Not commenting; just reporting.)

 _/|_    _______________________________________________________________
/o ) \/  Mike Taylor   <mike@miketaylor.org.uk>   www.miketaylor.org.uk
)_v__/\  "Obstfledermause!  Nehmen Sie sie, so lang sie noch heiss
         sind!  Sie sind lieblich" -- Andreas Pagel.