Re: Stegosaur plates as heat exchangers

[Stanley Friesen <sarima@ix.netcom.com>]

At 11:47 AM 6/13/97 -0500, Joshua Dyal wrote:
>OK.  ..., Dacentrurus, another stegosaur, had no plates at all--
> just spikes all the way up his back.
>
>So S. stenops had plates that could have made good heat exchangers, 
>but the examples I gave got progressively worse until Dacentrurus, 
>who couldn't have used his spikes for anything other than defense.

Or for display.  (And as defenses they would be most useful in
*intra*-specific interactions).

Still, this is a good point, IMHO.

> ... To me, this seems like very strong indirect evidence that even
>big plated stegosaurs like S. stenops must have used the plates for
>defense,

The plates of _Stegosaurus_ are really pretty useless as defenses. They do
not cover any critical body part, and are arranged poorly to intercept the
most likely attacks.  They *do*, however, have the effect of greatly
increasing the apparent size of the animal in lateral profile.  This is an
established category of display function.  It is why cats arch their back
when angry.  _Stegosaurus_ just had a built-in arched back!

--------------
May the peace of God be with you.         sarima@ix.netcom.com
                                          sfriesen@netlock.com