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Re: The Lost World errata

>From: jpoling@infinet.com (Jeff Poling)
 > ... In the book, the hadrosaurs (at
 > the very least, maybe other dinos as well) could not see Grant and the kids
 > unless they moved.  This was explained as being the result of their DNA
 > being blended with amphibian DNA (the implication being, I guess, that
 > amphibian eyesight is based on movement).
In at least some amphibians (frogs to be precise), *awareness* seems
to be triggered by movement.  That is, frogs tend to ignore stimuli
that are not moving relative to the eye.  This is more of a limitation
of the nervous system's manner of precessing the visual information
than of the eye itself.

For frogs, which eat flies and run away from big animals, this is
quite adequate (large moving object = danger, small moving object
=> potential food).  But this is actually very specialized, and would
not be very effective for most other lifestyles (aka niches).

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.