labral teeth

[mtaylor]

Please, I need help.  I am a teacher trying to do an activity on seashells and I need to know the purpose/function of labral teeth on cowries.  Any reference on general anatomy of shells you can suggest would also be helpful.  Thanks in advance!

[paul monfils]

Wow, tough one!  I was looking forward to gaining a little information on this matter myself, and figured it wouldn't be difficult to find since I have a pretty substantial conchological library.  But, after going through The Living Cowries (Burgess); Cowries of the World (Burgess); A Guide to Worldwide Cowries (Lorenz & Hubert);  Cowries and their Relatives of Southern Africa (Liltved);  The Invertebrates, Volume VI, Mollusca (Hyman); Living Marine Molluscs (Yonge & Thompson); and 7 or 8 more general volumes, I did not find a single word suggesting any purpose or function for the dentition of cowrie shells, labral or columellar.  I'll post this query on the Conch-L listserve also, and perhaps someone there will have some suggestion.  If so, I'll post the information here.

I would like to offer some possible help in a different way though.  I have been a shell importer/dealer for 40 years, and as such have thousands of shells on hand, which include many specimens that I don't consider suitable for sale due to growth lines, small chips, dull spots, etc., but which are still nice shells and great for classroom use.  Every so often I send a box of such shells to a school, scout camp, etc.  They are all labeled with scientific name and geographic locality of origin.  If this sounds like something you could use, email me and tell me a little about the classroom activity you are doing, and I'll send you some suitable shells.

<!-- e --><a href="mailtoaulCyp@cox.net">PaulCyp@cox.net</a><!-- e -->

.  <span class="petit">--Last edited by Paul Monfils on 2009-05-10 21:45:35 --</span>

[dave r]

Just to chip in my two pennorth, I did read somewhere, but can't remember where, that the labral teeth on cowries were a method of strenthening the narrow aperture. This would make it more difficult for a crab or other predator to gain access to the mollusc by breaking away the aperture. I have seen other shells with the aperture chewed away by Snappers etc. that got the creature out.
Dave

[mtaylor]

<blockquote><p><b>Quote :</b><table width="80%" border="1" style="border-color:#000099;background-color:#CCD4EC" cellspacing="0" cellpadding="0"><tr><td class="petit">Dave r wrote : Just to chip in my two pennorth, I did read somewhere, but can't remember where, that the labral teeth on cowries were a method of strenthening the narrow aperture. This would make it more difficult for a crab or other predator to gain access to the mollusc by breaking away the aperture. I have seen other shells with the aperture chewed away by Snappers etc. that got the creature out.
Dave </td></tr></table></p></blockquote>

[mtaylor]

Thanks for that, sounds reasonable.

[paul monfils]

There has been quite a lively discussion of this on Conch-L.  Rather than reposting it all here, you can read the various posts by going to:

<a href="http://www.listserv.uga.edu/archives/conch-l.html" target="_blank"><!-- m --><a class="postlink" href="http://www.listserv.uga.edu/archives/conch-l.html">http://www.listserv.uga.edu/archives/conch-l.html</a><!-- m --></a>

Click on "search the archives" then type the word "dentition" (without the quotes)  into the "subject" box (not the main search box at the top) and hit return  <span class="petit">--Last edited by Paul Monfils on 2009-05-14 03:47:03 --</span>