Folks,
 
Please read my article in American Conchologist 25(1):25-26 (March 1997), I
addressed all these points there. Or maybe it could go up on ConchNet for
those who don't have or don't want to look at the paper version.
 
Two quick responses. There are fish in the deep sea that produce light, so
it still pays to be camouflaged. There is no evidence that waste products
are stored in shells--why not just excrete them into the water?
 
Aydin's suggestion that pigments could attract epibionts that help
camouflage shells is intriguing. This suggests several tests. Do the
epibionts settle preferentially on shells as opposed to rocks or dead coral?
Should such pigments be uniformly distributed or patchily distributed in the
shell? If the hypothesis is true, I would guess patchily, since less pigment
would need to be produced, and the epibionts would quickly grow together to
cover the whole shell. Are epibionts more often found on uniformly colored
or patterned species? Has anyone collected specimens where the epibionts
have just settled and match the pattern on the shell?
 
I'll be out of town for a couple of weeks, so I won't be able to continue
this interesting debate after tomorrow.
 
Gary
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Gary Rosenberg, Ph.D.                     [log in to unmask]
Malacology & Invertebrate Paleontology    gopher://erato.acnatsci.org
Academy of Natural Sciences               http://www.acnatsci.org
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