RE: Sclerotic rings

["King, Norm R" <NKing@usi.edu>]

-----Original Message-----
From: John Fredriksen [mailto:jfredriksen@boston.sisna.com]
Sent: Thursday, April 05, 2001 10:10 AM
To: dinosaur@usc.edu
Subject: Sclerotic rings


>A question for all you mesozoic mavens out there.
    Marine reptiles developed sclerotic rings around their eyes as a
means of coping with high pressure during deep dives, correct? Well, do
whales have such structures and, if not, how do they compensate for the
pressure without ruining their eyes?<


I think this interpretation is like a "just so" story.  That explanation
seems to make sense, so it must be.  But is that the reason for sclerotic
rings in other reptiles and birds?  Not likely.  So, if you ask me, it's not
much more likely for marine reptiles.  That being the case, I do not think
we are compelled to explain why whales don't need them.