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Re: Dino feathers=Ptero fur?
On Thu, 8 Feb 1996, Nicholas R. Longrich wrote:
> Arctometatarsialian has been used about 500 times, but could
> somebody please define it? And did those cladograms actually put T. rex
> closer to modern birds than Archaeopteryx, or was I misreading that?
The Arctometatarsalia are a group of Cretaceous theropods (tyrannosaurs,
ornithomimids, and troodonts are the best-known representatives),
characterized by, among other features, a foot constructed with the top
of metatarsal III hidden behind metatarsals II and IV and tapering to a
point (see crude attempt at diagram below):
_ _
| | |
| | |
/ / \ \
|_|_|_|
II III IV
(cranial view of left metatarsus)
To answer your second question:
Yes, based on foot and braincase features, I believe arctomets (including
_Tyrannosaurus_) to be more closely related to modern birds than
_Archaeopteryx_, although Tom and George, just to name a few, disagree.
Nick Pharris
Pacific Lutheran University
Tacoma, WA 98447
(206)535-8204
PharriNJ@PLU.edu
"If you can't convince them, confuse them." -- Harry S Truman