Re: Sclerotic ring in eyes

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

Mark Shelly wrote:
> 
>    What is the purpose of the slerotic ring, the bony eye ring seen in
> sketital restorations?  What does it do?  Does it protect the eye from
> impacts? Is it in the eye itself?  Can it open?  Do Birds, aligators, or
> other peptiles still have this feature? Mark Shelly

        Sclerotic rings are found in most reptiles, including many
archosaurs (dinos, ichthyosaurs, pterosaurs). I'm not sure about
crocs though, I suspect a sclerotic ring would make raising and
lowering the eyes difficult.
        They seem to function as supports for the eye, probably
lying behind it, since many reptile eye sockets tend to be larger
than the eye itself. Have a look at the size of tyrannosaur or
sauropod eye holes and you can see that the actual eye would only
fill a small portion of the hole (usually the upper part). The ring
would have been rigid.
-- 
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        Dann Pigdon
        Melbourne, Australia

        Dinosaur Reconstructions:
        http://www.geocities.com/capecanaveral/4459/
        Australian Dinosaurs:
        http://www.alphalink.com.au/~dannj
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