Here's a great book for any of you interested in this topic!
"Climbing Mount Improbable" by Richard Dawkins (of "The selfish Gene" fame).
Published by W.W.Norton & Company.
It gives a fantastic discussion of macroevolution ("mount improbable") vs
microevolution.
There is a big chapter on evolution and comparative anatomy of the
eye "The Forty-Fold Path to Enlightenment", and one on shell shape and design
called "The Museum of All Shells".
It's a great read.

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Peter Egerton, Vancouver, Canada
Collector of worldwide Mollusca
http://www.intergate.bc.ca/personal/seashell/index.html
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