Re: Horner's JP3 interview

["Mickey Mortimer" <Mickey_Mortimer11@msn.com>]

Steve Brusatte wrote-

> >"We do know that [the spino] had a skull that was eight feet long, and a
body that
> >was about 60 feet long," Jack Horner [said].

>Not to say that it was impossible for Spinosaurus to reach this size.  In
fact, Spinosaurus >may have gotten this big, although it is a big if...
And, I have no problem recognizing >Spinosaurus as one of the largest
carnivorous dinosaurs known.  However, I would really >like to know where he
is getting these numbers.  It does seem like he is getting them from
>somewhere...but where??

Just how long was Spinosaurus?  If we assume the dorsals are from a relative
of baryonychines (contra Rauhut 2000), we can use their size to estimate
that of Spinosaurus.  Suchomimus has a more cmplete tail than Baryonyx and
measured 11.0 meters long.  Scaling the humerus to Baryonyx indicates a
length of 9.1 meters for the latter taxon, very close to Charig and Milner's
(1997) estimate of nine meters.  Nearly all the dorsals are preserved in
Baryonyx, increasing in length to the last, which is 110 mm long.  The
largest and most posterior of Spinosaurus' dorsals (dorsal i of Stromer
1915) is about 210 mm long.  Scaling this to Baryonyx's last dorsal (scaling
to more anterior dorsals would give greater lengths) gives an estimated
length of 17.4 meters for the holotype of Spinosaurus aegyptiacus.  This is
equivalent to 57 feet, so I think Horner was very accurate in his report.

Mickey Mortimer