![](http://www.alamy.com/thumbs/6/99B34D64-DCC5-437A-A3FA-EE1EAA993B99/2EDN8P8.jpg)
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
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.
Size: 5800px × 3795px
Location: Zanzibar, Tanzania
Photo credit: © Nick Greaves / Alamy / Afripics
License: Licensed
Model Released: No
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