Re: Article: T. rex Had "some of the best vision in animal history"

[Michael Habib <mhabib5@jhmi.edu>]

> Orbit size estimate: In extant reptiles and birds, how "tight" is the
> correlation between calculated orbit diameter (as done by the "party
> balloon" test in the Stevens paper) and the animal's actual eyeball
> diameter?  Is there any type of consistent ratio that fits this
> relationship across taxa?  And are there any extant exceptions to this
> rule (e.g., animals with a huge orbit with a small eyeball; or with a
> small orbit with a huge eyeball)?

For birds, the correlation is very tight, but only if you have the 
sclerotic ring to work with as well.  Orbit size alone does not have a 
particularly good fit; though it is better for birds than for mammals.

There was an SVP talk, and a poster, on reconstruction of avian eye 
size from osteological evidence.  If I remember correctly, it was at 
the most recent meeting; I will try to track it down.  Does anyone here 
know the paper/poster I refer to, and recall the author(s)?

--Mike H.