Marcus,

However, they must crack first before they explode :-)
Never having seen it happen, only seeing the end results in museum
collections, I would agree that they may have exploded.

> Correction - Paryphantas explodes! I had a few on my desk and one of them
> literally blew up making a
> loud sound and launching small pieces around...
>
> Marcus
>
>
>
> No there are also gastropods that crack. One specific example are members
> of the genus Paryphanta.
>
> I suspect that the cause of the cracking is due to the the different
> expansion and contraction rates of the periostracum and mineral matrix.
> For example, if the mineral matrix is thin and the periostracum relatively
> thick, when the relative humidity varies, these layers will contract (or
> expand) at different rates. The mineral matrix may break while the thicker
> periostracum holds tight.
>
> The converse would also be true. If the mineral matrix was thick (think
> Mercenaria) and the periostracum thin, the matrix will not crack yet the
> periostracum will crack and flake off.
>
> Regards,
> Charlie
>
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Regards,
Charlie
.................................................
Research Associate - Section of Mollusks
Carnegie Museum of Natural History
Pittsburgh, PA, USA

Assistant Professor - Family Medicine
Fellow-American Academy of Family Practice
Fellow-Academy of Wilderness Medicine

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