Fwd: Re: Queries

[tidwell@ix.netcom.com (Virginia Tidwell)]

Tom Holtz wrote:

Many dinosaurs had hollow bones, theropods in particular.  Some 
theropods
and sauropods have extensive systems of pleurocoels in the vertebrae 
(ask
Brooks Britt about this - he ought to know something on the subject...).
Theropod longbones are all hollow.

>3) Have carpo-metacarus or tars-metatarsus (fused hand/wrist, 
foot/ankle)
>been recorded from dinos?

The carpals of several coelurosaur groups show a trend towards fusion,
forming the semilunate carpal block (which is in origin formed of at 
least
two carpals).  In Avimimus, a true carpometacarpus is formed.

Ceratosaurians, Avimimus, and Elmisauridae all show true tarsometatarsi.
Archaeopteryx itself only shows the beginning of this structure.        
***********

While researching this question today, I came up with similar lists of 
dinos having carpometacarpi and tarsometatarsi.  And many theropods 
showed up as having hollow long bones, esp. Ceratosauridea 
(Ceratosaurus, Dilaphosaurus, Coelosaurus, etc.) as well as some 
Coelurasaurs.  But your statement that all theropod long bones are 
hollow was a surprise.  We have a T-rex femur that we are currently 
repairing that seems to be quite solid, as shown in the cross sections 
of several clean and not-so-clean breaks.  I don't think that it is a 
hollow bone filled with matrix as our Coelophysis long bones are.  Are 
all of the Carnosauria included in the hollow bone catagory?
         Puzzled in Denver,
          Virginia Tidwell
                    










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