As mentioned in my first post in this thread, I needed to look at some of my
cowry shells to find examples of how the ridges in repaired juvenile cowry
shells relate to the 'teeth' on the larbal side of the aperture.

I have uploaded a new page to the cowry.org website which shows several up-close
images of this type of cowry shell structure. It can be accessed at:
http://cowry.org/research/plating.htm

Aloha,

Bob Dayle
webmaster - http://cowry.org

______________________________________________________
Quoting John Varner <[log in to unmask]>:

> A similar discussion came up a few years ago on some other aspect of
> molluscan morphology.  I made the following comments, more or less, at that
> time.  Namely, not all changes in appearance or structure are driven by
> positive adaptive benefit.  Rather, if a mutation occurs that doesn't
> negatively impact survival, the animal or plant that expresses it can
> survive, reproduce, and give rise to a new specie.  How else to account for
> the myriad patterns of cone shells, which are never even visible in vivo
> beneath a periostracum or calcine accretions, or the bizarre differentiation
> among the spines of murex species?   Humans have an innate capacity to
> perceive variation and a need to impose order on their perceptions, and
> trying to explain the fine points of cowrie dentition might say more about
> the genus Homo than the genus Cyprea.  If dentition offered survival benefit,
> why would it manifest only in mature specimens, and not in smaller, more
> frail juveniles?

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