Sclerotic ring

Sclerotic ring

Sclerotic rings are rings of bone found in the eyes of several groups of vertebrate animals, except for mammals and crocodilians.cite web |last=Motani |first=Ryosuke |url=http://www.ucmp.berkeley.edu/people/motani/ichthyo/eyes.html |title=Eyes |accessdate=2007-07-06 ] They can be made up of single bones or small bones together.cite web |url=http://www.palaeos.com/Vertebrates/Lists/Glossary/GlossaryS.html |title=Palaeos Vertebrates: Glossary S |accessdate=2007-07-06 ] They are believed to have a role in supporting the eye, especially in animals whose eyes are not spherical, or which live underwater. Fossil sclerotic rings are known for a variety of extinct animals, including ichthyosaurs, pterosaurs, and dinosaurs,cite web |last=Pigdon |first=Dann |url=http://dml.cmnh.org/1997Oct/msg00393.html |title=Re: Sclerotic ring in eyes |accessdate=2007-07-06] but are often not preserved.

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