Re: sclerotic rings

[Flyinggoat@aol.com]

>If eye linear dimensions (and therefore the binocular
>separation) expand with body size linear dimensions, I suppose >that scales
up.  I've always has the impression that eye size does >not scale that way,
though, that if you double the size of the >animal, in general the size of
the eye is less than doubled - but I >have no evidence to support this.

   I believe eye size is dependant of the use the animal puts them to, and
not dependant on proportion.  For instance the horse has the largest
eye-to-body size of land mammals because it's very dependant on seeing
predators and running away from them.  An elephant, though large than a
horse, does not have proportionally larger eyes because it did not evolve the
dependance on eyesight as much as the horse did. 
   Do any modern animals other than birds, fish, and reptiles have sclerotic
rings?  (I think I'm asking if mammals have them, at all?)   I believe they
were found in both pterasaurs and ichyosaurs (as Tom mentioned), but are they
also found in mosasaurs, and plesiosaurs?

Betty Cunningham(Flyinggoat@aol.com)
illustrator, animator, and likes to collect dead things