My mind is clear now - the foot moves the beast.

Muscles in the foot might use the ridges as a place to
grip and propel the shell forward.  Consider sand in which it moves.

Sand isn't firm and can't be relied upon to provide a push off point.
The foot anchors itself and with muscles it moves the shell with the
assistance of the teeth - they being the shell hold and the foot stem
on the snail.  Something like a ratchet - up and lock.  Move foot. Up
and lock.
Otherwise the foot might pull the snail out of the shell if the shell
was in stiff or moving sand.

Maybe someone in Language Arts could develop a communication line
in order to find the answer ! ;=)

Martin

Martin H. Eastburn wrote:
> I tend to agree that the teeth are mechanical parts.
>
> A thought only on my part was a water flow when sitting on most
> anything or even over the mantle when out moving around.
>
> I think we need a Technical / biology type that knows the snail functions
> to be certain.
>
> Are there mantle muscles that press those into place
> as the shell begins to grow ?  Those needed for movement and control.
>
> Seems so simple, but with many complex options.
> Martin
>
> Ellen Bulger wrote:
>> I'm just going on a limb and say the "teeth" are actually ridges. The
>> ridges would strengthen that part of the shell. My sense of olives
>> versus cowries is that olive shell walls are thicker in relation to
>> the overall size of the shell. As the cowrie shells are bigger,
>> relative to their overall weight, they benefit from a little
>> structural reinforcement around the aperture.
>>
>> Just a guess.
>>
>> It seems like the kind of thing that Vermeij would get riffing on.
>> Does he have anything published on this?
>>
>> On Sun, May 10, 2009 at 3:55 PM, Paul Monfils <[log in to unmask]
>> <mailto:[log in to unmask]>> wrote:
>>
>>     I received a query about the apertural teeth of cowrie shells –
>>     namely, do they have any purpose or function?  I couldn’t find a
>>     word on the subject in any of the standard volumes on Cypraeidae
>>     (Burgess, Lorenz & Hubert, Liltved, etc.) or in any of several
>>     texts on molluscan development, anatomy, ecology, etc.  Does
>>     anyone have any information on this?  Are the “teeth” strictly
>>     decorative?  Ovulidae seem to get along just fine without them.
>>
>>
>
> --
> Martin H. Eastburn
> @ home at Lions' Lair with our computer lionslair at consolidated dot net
> TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
> NRA Second Amendment Task Force Charter Founder
> IHMSA and NRA Metallic Silhouette maker & member.
> http://lufkinced.com/
>
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--
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/

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