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Re: My Gr. 9 Science Fair Project: Questions
Dr Paul M.A. Willis wrote:
> Do not underestimate the stealth of a croc on the hunt. There are numerous
> documentaries that show zebras and wildebeast quietly drinking at a river
> only to find that there is a croc lying in wait in the middle of them.
>
> [ Sorry to interject, but dinosaurs probably had better color vision
> than most mammals and may have been sensitive to optical polarization
> as well. The latter would be particularly helpful in allowing an
> animal to see under the surface of the water because the polarization
> of reflected light would be different from the polarization of light
> transmitted from under the water's surface. -- MR ]
Humans also have good color vision.
Having *been* to the everglades, I can tell you, croc in the water
are blessed hard to see, even *with* color vision.
For one thing, as often as not the water is quite opaque.
All one can generally see of a croc in the water is the tiny
nose sticking out - if that much. In an area of reeds or
rushes even that would be rather hard to spot.
swf@elsegundoca.ncr.com sarima@ix.netcom.com
The peace of God be with you.