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Re: Willie Wonka and the New Papers

----- Original Message -----
From: "Michael Mortimer" <mickey_mortimer111@msn.com>
Sent: Monday, March 17, 2008 11:42 PM

And at long last my e-mail service has included a way to make messages plain text, thus I can return to the DML...

Sorry for the shock: it's plain text _without line breaks_, so some readers, and probably the archives, will get the "truncated" message instead. I hereby repost the whole thing.

Microsoft has been bashed a lot, but when Outlook Express says what you write is plain text, it is plain text!

David Marjanovic wrote-

So *Megalosaurus* is not a spinosauroid at all... Yay Torvosauridae.

Yet reading the paper results in seeing only one character suggested that would exclude Megalosaurus from the Spinosauroidea- the third alveolus isn't largest (the fourth is). They further state that in spinosauroids (Torvosaurus, Dubreuillosaurus, Eustreptospondylus, Magnosaurus, spinosaurids), the dentary is laterally expanded to accomodate this alveolus, whereas Megalosaurus shows a much more subtle expansion around the third to sixth alveoli.

This is fine, but the authors also note a character of Megalosaurus which is only found in some spinosauroids- paradental groove open only anteriorly. This is shared with Dubreuillosaurus and "Walkersaurus", but not with Magnosaurus or Torvosaurus among spinosauroids.

I should try adding the holotype to a non-maniraptoriform supermatrix I've been working on (including all codings from Smith et al., 2007; Tykoski, 2005; Carrano and Sampson, 2007; Rauhut, 2003; Azuma and Currie, 2000; Allain, 2002; Ezcurra and Novas, 2006; etc.). Notably, Poekilopleuron falls out basal to the rest of the megalosauroids, leaving open the possibility Megalosaurus has a similar position and simply hadn't evolved the expanded third alveolus and dentary yet. It would still be a spinosauroid though, using Holtz et al.'s (2004) stem-based definition. Using Sereno's node-based (Torvosaurus+Spinosaurus) definition, even taxa like eustreptospondylids and Poekilopleuron fall outside Spinosauroidea in the supermatrix.

Mickey Mortimer

Wow. Is that supermatrix your thesis?