Re: Theropod stance balance

[Phil Bigelow <bigelowp@juno.com>]

On Thu, 14 Apr 2005 17:27:10 -0700 (PDT) don ohmes <d_ohmes@yahoo.com>
writes:
> 
> 1. I think they had lots of time to get as big as they
> could. Experimental evidence indicates that
> evolutionary changes in morphology can happen fairly
> quickly when measured in generations.


I'm not claiming that there was an *evolutionary* reason for a
carnivorous dinosaur to get bigger than T. rex.  I'm saying that,
biophysiologically, there is nothing constraining bipedal carnivorous
dinosaurs to a maximum mass of a T. rex (or of Giganontosaurus, for those
who think it was even bigger).


> 2. The morphological refinements you mention indicate
> a strong selective pressure for the re-allocation of
> mass. I take this to mean that if Sue got bigger, the
> mass re-allocation would need to continue. If Sue got
> bigger, could she significantly increase bone
> pneumaticization or neck recurve?


Using ostriches as a comparison, then yes.  IMHO, Tyrannosaurs had a long
way to go to evolve maximum movement/mass efficiency.


> I'm just guessing,
> but her arms look so small they could be removed
> entirely without affecting the center of mass. What
> are the other morphological options here?


Achieving a secure hold during mating is the only reason that I can think
of for retaining any arms at all in a T. rex.  [were we all so blessed to
have a secure hold in our mating habits].


> 3. <<"Or possibly like ostriches get up after having
>  fallen (anyone know how
>  ostriches recover from a fall?).">>
> 
> Thats a great idea! I second the question. Anyone out
> there happen to know?
> 
> 4. << "3) then simply stand up." >>
> 
> LOL, you are obviously young and spry.


Hey dude.  I will die young, psychologically at least.
Spry?  My spryness ended roughly at the end of the Clinton
administration.

<pb>
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