From: "David Marjanovic" <firstname.lastname@example.org> To: email@example.com Subject: RE: A question about Mickey's non-theropod tree Date: Wed, 2 Nov 2005 23:27:06 +0100 (MET)
Could you forward this to the list? I still can't post... apparently some CMNH server treats me as spam.
------------------------------- Thanks to Jordan for having forwarded my previous message!
> The position of Mesosauridae is based on Modesto's (1996) thesis. [...]
In their paper on the redefinition of Reptilia (to accommodate the instability of the turtles... instead of just dropping the name!), Modesto & Anderson (2004, Systematic Biology) never imply that this topology might be possible.
The taxon selection strikes me as rather small. Few basal diapsids and "anapsids". Even basal (insectivorous) captorhinomorphs are IMHO underrepresented. The surprisingly large number of younginiforms suggests that time/computer power constraints were not that much of an issue.
> If he plots taxa on a line of potential ratios for a character (e.g. > humerofemoral ratio) and sees no distinct gaps between where taxa plot, > he drops the character. This does make it more objective in a way,
It would do so if he had used statistics to show that, with 95 or something % probability, there is no gap :-)
Unfortunately TNT, which allows you to use continuous characters (right?), wasn't yet available.
> molecular phylogenies finding turtles sister to Archosauria (Zardoya and > Meyer, 1998; Hedges and Poling, 1999; Kumazawa and Nishida, 1999; Rest > et al., 2003; Iwabe et al., 2005),
Or sometimes inside it.
IMHO this reeks of long-branch attraction. *Alligator mississippiensis* has a branch as long as the Mississippi.
> and phylogenetic taxonomy
> defining Anapsida as turtles and taxa more closely related to them > than to extant saurians.
(In this wording, ironically, there would be much less of a problem -- _if_ by Sauria the group were meant that most herpetologists who use it still mean by that name, namely the paraphyletic lizards without snakes and sometimes without amphisbaenians.)
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