Re: re: T. rex

[Stan Friesen <swf@tdat.ElSegundoCA.NCR.COM>]

 > Horner is sadly mistaken in saying active predators require their
 forelimbs
 > in predation.

Quite.  Even if I am wrong about the possible use of the forelimbs,
the Bakker/Paul style of slash and follow hunting is still quite
acceptible a method.  And a tyrannosaurs hind limbs are quite
powerful, so they could possibly deliver a fairly substatial
killing blow.
 >
 > Actually, Alexander's studied was seriously flawed.  He used an 8
 tonne mass
 > for T. rex, based on an incorrect scaling (a hip height of 3.6 m).

Urp - *8* tons!  That is a truly *old* weight estimate.
[It is also the almost highest that has ever been published].

4-5 tons is more like it.

 > The
 > actual specimen "modelled" (its an atrocious model, by the way) has
 a hip
 > height of less than 3.2 m.  Scaled correctly, the mass is some 4.6
 tonnes,
 > and the strength of the value almost doubles.  However, Farlow et
 al. have a
 > paper in review which might change some of this...

This sound more like it.
 >
 > The evidence for running tyrannosaurids is much stronger than for
 running
 > ceratopsians.  The whole hind limb of a tyrannosaurid is desinged to
 be
 > elongated and gracile.  Ambush still might work, given the forested
 nature
 > of some the habitats they lived in, but pursuit still is possible.

Quite - I remember an old study comparing Albertosaurus with
Daspletosaurus where the difference in the limb proportions
was of a sort to suggest one was more 'ambush' oriented than
the other.  (The relative sizes of the upper and lower limb
bones are different in 'runners' versus 'sprinters').

[I think the study was actually the article that *defined*
Daspletosaurus as distinct from Albertosaurus, and this limb
proportion difference was one of the defining differences]

swf@elsegundoca.ncr.com         sarima@netcom.com

The peace of God be with you.