Re: Spinosaurus aegyptiacus holotype

["Jaime A. Headden" <qilongia@yahoo.com>]

Mickey Mortimer (Mickey_Mortimer111@msn.com) wrote:

<The dorsal neural arches are not fused to the centra.>

  Though it may not have been "immature," as even in some birds and
mammals, adulthood and maturity is still known with open neurocentral
sutures. SOME of the dorsals and the cervicals shown closed neurocentral
sutures.

<I don't see why people ignore Spinosaurus' size, or claim it's uncertain
that it was larger than Tyrannosaurus.  Dorsal central length is one of
the best indicators of total length, and Spinosaurus' were HUGE.>

  Though the centra are fairly long, note that in *Tyrannosaurus,*
cervical count is lower than in, say, *Dilophosaurus.* Dorsal and
cervical, as well as caudal counts, vary among species, and the estimates
should account for this, as well as that the vertebral counts in
*Baryonyx,* the most complete relative of *Spinosaurus,* is unknown. But
yes, Mickey's estimates take into account what would happen if you scaled
up *Baryonyx* up, and expanded the ribcage, suggestive a few extra hundred
kilos of mass beyond the scaled ratios. That's assuming there is a direct
scaling inferrence here, and *Spinosaurus* didn't depart somehow, and that
its femoral length, long-time the friend of allometric scalers and mass
estimates, is unknown. I beleive it was this that has lead to skeptics
stating the length and mass are relatively unknown and one shouldn't be
making easy comparisons.

=====
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.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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