The tight spiral of the Tun Shell, a marine mollusc. As the animal grows the mantle secrets calcium carbonate to grow the shell to accommodate itself

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The tight spiral of the Tun Shell, a marine mollusc. As the animal grows the mantle secrets calcium carbonate to grow the shell to accomodate the increase in body size.

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Size: 5800px × 3795px
Location: Zanzibar, Tanzania
Photo credit: © Nick Greaves / Alamy / Afripics
License: Licensed
Model Released: No

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