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Re: Megalosaurus = Torvosaurus in Europe



Mickey Mortimer (Mickey_Mortimer111@msn.com) wrote:

<The latter is more similar to Eustreptospondylus (=Magnosaurus?) because
it shows- paired hypapophyses;>

  Just to clarify, these are called carotid processes by Allain, not
hypapophyses, and many other bird researchers (including Kurzanov) use the
same terminology; and as I believe the latter term is restricted to the
single ventral process as in birds, not as in mammals. Homologies in
mammal and bird vertebrae may cause the terms to become problematic:

  Mammals have carotid processes, but these are formed from the
parapophyses, and this is why the lacuna between cervical rib and centra,
provided by the par- and diapophyses are called carotid foramina. This
latter is true for birds, as well. Loss of cervical ribs in mammals
results in a muscular effect for the parapophyses, and the carotid
arteries run parallel to these structures. Hypapophyses lie medial to the
parapophyses, and in this the processes of Allain are not carotid processes.

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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