Re: Stegosaur plates as protection......

[Dann Pigdon <dannj@alphalink.com.au>]

Randy King wrote:
> 
> A few animals may attack through the back, but most will attack the
> soft vital organs; this is usually either the throat or the abdomen.
> Animals with defenses based on the back tend to be smaller and can
> protect their stomach and throat through other means, like the
> armadillo or porcupine.  Otherwise, I think the soft areas are more
> important to protect.
> 
> Perhaps this is different for a therapod; though, that has the strength
> to crush through the bones.  But that still assumes that the giant
> therapods were the primary threat to teh stegasaur. This almost feels
> like a circular argument to me: If the stegasaur was only preyed upon
> by therapods, he would develop a therapod defense; the therapods would
> go after easier prey; the stegasaur would lose the genetically costly
> defense.

For a start there are no modern analogies that come close to the size
of a large theropod. Lions may come close, and when attacking cape
buffalo they DO attack the spinal colomn. They leap onto the hind
quarters and bite and claw persistantly at the base of the tail.
This way they avoid the pointy end of the beast and at the same time
may cripple it so it can not run away so quickly.

As for the evolutionary synopsis put forward, creatures do not
evolve in turns, but at the same time. In Crichton's JP sequel he
mentions many chaos theory buzzwords, one of them being the "Red
Queen" effect, whereby creatures evolve at a frantic rate just to
stay even with each other. AS for stegosaurs loosing their plates if
no theropods attack them for long enough, even modern predators will
occationally try to take a porcupine or an armadillo, so no defence
is perfect.
-- 
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        Dann Pigdon
        Melbourne, Australia
        http://www.geocities.com/capecanaveral/4459/

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