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Re: How would Tyrannosaurus approach a Triceratops?
In article <firstname.lastname@example.org>, Neal
> Use the superior eyesight and elevation of the head
Elevation of the head is OK, but the evidence for "superior
eyesight" in T-rexes (over ceratopsians) is? Increased relative size of
optical cortices compared between the two species? Could one make an
assessment of optical acuity from diameter of the eyeball (large
diameter is necessary to get a large pupil, hence 8m+ telescope
mirrors, but there's a lot more in a vertebrate eye than just the
entrance pupil, which could affect acuity in both directions)? In
modern reptiles (or birds?), how well does the scleral (sp?) ring
compare with pupil diameter and (our perception of) visual acuity? And
what about those eagle-eyed eagles with eyeballs much smaller than us
practically-blind spectacle-wearing humans?
Thinking more about the physics of eyes (inevitable if you've
ever read Dawkin's 'Mt. Improbable'), just what sort of focal plane
acuity variations would one get from having a slit-like pupil, or even
some of the <strikeout>weirder</strikeout> less symmetrical pupil
shapes found scattered through the vertebrates?
Location: 57°10' N, 02°09' W (sub-tropical Aberdeen), 0.021233
Written at Thu, 18 Aug 2005 09:34 +0100
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