Re: Spinosaurus

["Jonathan R. Wagner" <znc14@ttacs1.ttu.edu>]

At 03:04 PM 11/27/96 +1030, Dinogeorge wrote:
>There are quite a few differences between _Spinosaurus_ and _Becklespinax_ in
[...]
>papers). In _Spinosaurus_ many of the dorsal vertebrae--particularly toward
>the front end of the animal (cranial dorsals)--articulate like ball and
>socket joints (opisthocoely), indicating a certain amount of mobility: the

        If I recall correctly, opisthocoelous dorsals are currently
interpreted as a size-related feature and are found in several
non-sail-backed large theropods.  This does not, however, eliminate the
George's theory.

>muscular flesh. So it's likely that _Becklespinax_ sported a ridgeback,
>whereas _Spinosaurus_ had some kind of sail.

        I have been wondering if we may be overstating the possible
differences between _Metriacanthosaurus_ and _Becklespinax_.  Can anyone out
there sumarize the points that are made against a close relationship?
        Wagner

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| Jonathan R. Wagner                    "You can clade if you want to,     |
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