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re:dinosaur eyeballs



>A short while back, someone (could have been Betty) said that all >birds
have fairly bog-standard rounded pupils. This seems >essentially correct, but
note that Adelie penguins (_Pygoscelis >adeliae_) have elliptical shape ones.
Also, some fruit pigeons >(one of which has the generic name _Ducula_) _seem_
to have a >bit of the pupil that dips down about 45 degrees at the rostral
>(yaawn) end.

(it was me) 
    Are there any birds with slit pupils?   Are there any birds that show the
whites of the eyes?   Do crocodiles have round pupils or slits (and if slits,
which way do they slit?).  Do crocodiles and other large modern reptiles show
whites of the eyes?   
    Are we looking at the high probability that dinosaurs had round eyes that
showed no whites?  It would seem that in 145 million years, some variations
in eye shape might have come up:  it hasn't taken mammals more than 70
million years to come up with the variety they have, (and conversely, why
don't birds, with 85? million years behind them show more variety as to shape
(not color). 

-Betty Cunningham
(Flyinggoat@aol.com till the end of the month)
(bcunning@nssi.com at work)
(bettyc@flyinggoat.com starting the end of the month)