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Re: Progressive birdyness?
At 02:09 PM 5/9/97 -0600, LN Jeff wrote:
> Can anyone tell be if dromeosaurs and troodontids showed a tendancy
>to get more birdlike with time? Is _Velociraptor_ more birdlike the
>_Deinonychus_? Are Late Cretaceous troodontids more birlike then earlier
>ones? If so, it would be a rather puzzling trend considering birds
>evolved in the Jurassic.
Not really, as far as is known. Early Cretaceous dromaeosaurids and
troodontids are not particularly less bird-like than Late K forms. Okay,
Utahraptor and Deinonychus seem to be more bulky than Velociraptor, but this
may simply reflect their bigger size overall.
One of the few groups of coelurosaurs which becomes more "bird-like" through
the Cretaceous are ornithomimosaurs, and this only because they lose their
teeth by the Senonian. (And, of course, losing their teeth makes them like
neornithine birds, not like classic Mesozoic birds!).
Thomas R. Holtz, Jr.
Vertebrate Paleontologist Webpage: http://www.geol.umd.edu
Dept. of Geology Email:firstname.lastname@example.org
University of Maryland Phone:301-405-4084
College Park, MD 20742 Fax: 301-314-9661