Re: Sauropod necks and rearing

["Ken Kinman" <kinman@hotmail.com>]

   For me the question is not whether they could rear up (there is little 
doubt that they could).  The question is how often and under what 
circumstances the big sauropods would use that ability.  It seems pretty 
safe to assume that they would do so when aroused by fear or the mating 
urge.
    But would a big sauropod rear up sort of like a begging puppy dog in 
the way that was shown in the early part of Jurassic Park?  Wouldn't natural 
selection tend to weed out those sauropods who reared up more often (or more 
vertically) than was necessary?  I can see a male sauropod perhaps doing 
that to intimidate another male, or a female trying to intimidate a predator 
threatening her offspring.  But the Jurassic Park scene just didn't ring 
true for me, and seemed contrived and forced like a circus animal performing 
a trick.  The movie-makers did not provide any good motivation for the 
sauropod to act in that manner.
           ------- Ken
****************************************
Greg Paul wrote:
> As for rearing sauropods I plotted data showing that most sauropods had 
> posterior dorsals stressed for bipedalism in the same manner as kangaroos 
> and giant slothes, and much stronger than mammals that rear only 
> occasionally in the wild such as horses and elephants (published photos 
> show them rearing to feed). There is a long line of excellent studies 
> demonstrating the specialized rearing adaptations seen in many sauropods 
> for rearing dating back to old Riggs about 100 years ago. There has never 
> been a study providing conclusive evidence that any sauropod could not 
> rear. That this subject remains controversial is more a sign of failure to 
> appreciate the anatomical evidence driven by inherently speculative 
> opinions that animals so big could not stand on two legs, or blood pressure 
> problems were too severe, than the existence of a real problem.


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