Re: Penguins And Rexes

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

David Marjanovic (david.marjanovic@gmx.at_ wrote:

<<Why people don't ask the questions "could bigass titanosaurs lie on their 
sides?">>

<Last I checked (years ago) titanosaurs were thought to be very round, even
somewhat dorsoventrally compressed, so this doesn't sound like they could roll
over on a side in the first place... how much sprawling did their forelimbs
allow?>

  How much of this was based on ankylosaur and scute confusion and how much was
based on actual titanosaur ribs? If I recall correctly, titanosaurs like
*Rapetosaurus* and *Saltosaurus* are about as narrow as other sauropods.

<If it completely trips, the head falls from a tremendous height, so I guess it
dies... but then I don't think it's likely to trip in the first place. Being so
huge, it has plenty of time to react. The apparently unossified carpals of
titanosaurs could have been an adaptation to cushion harder-than-usual
impacts.>

  This assumed the head was "from a tremendous height". Some people (Paul, for
example) consider the head of *Brachiosaurus* to be held habitually vertical or
semi-vertically, some more 45-degree or so (giraffe-style) and some nearly
horizontal (Stevens, for one). There does appear to be some evidence for both
sides.

  Titanosaurs like *Argentinosaurus*, like other titanosaurs, appear to have
had relatively shorter necks with more habitually lower postures than GSP
figures them, and many were so much smaller than an elephant it's unlikely the
"head from a height" model would seriously cause the damage needed to kill it
if it fell that an impact of imploding the chest cavity or crushing the
windpipe wouldn't. A good question to ask is do elephants trip? And if they do,
do they survive, and why (and why not, if they don't)? Then this model can be
applied. Similarly, as I was educated and reminded a while back, a moving body
doesn't fall straight forward, and a tripping rex may try to keep its balance.
The models for tripping and dropping bodies are based on vertical descents, but
the bodies of animals such as running rexes and sauropod bodies would be moving
forward, and this may ameliorate any impact forces along the venter. Or give
the animal a good chin ache and cries of "Mommy! My chest hurts!" in
brachiosaurese.

  ---

  BTW, isn't _kneme_ a feminine word (as is implied in the name *Bradycneme*),
but in combination would it not be _knemo-_ for *Eucnemosaurus*?

  Cheers,

Jaime A. Headden

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


                
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