I just received this question from Jorge Caceres in Mexcio.  I thought
some of you could help him out.
 
His email address is [log in to unmask]
 
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I am working with phenotypes of mussels shells and I am looking for
information about the significance of ribs on the shells of bivalves.
Could you help me in this sense.
Thank you very much in advance.
 
Jorge Caceres