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Re: dino eyeballs

        On Mon, 21 Aug 1995, Betty Cunningham (alias the flying 
goat) asked:

>. . . Do crocodiles have round pupils or slits (and if slits, which way 
>do they slit?).  

        Like other nocturnal animals, crocodylians pupils close 
to a vertical slit in bright light.  

>Do crocodiles and other large modern reptiles show whites of the 

        No, the whites of the eye do not show in crocodylians.  I 
suspect that this is also the case for other large reptiles.  The colour 
(color if you can not spell) of a crocodylian's eye is usually a pretty 
good match for that of its skin; so in most cases baby puke orange or 
greeny brown.

>    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).


Steve Salisbury
Vertebrate Palaeontology Laboratory
School of Biological Sciences
University of NSW, Australia