Ammonite Slab
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The ancient water-dwelling ammonite is a relative of the squid or octopus. This creature lived inside of a spiraling external shell, which provided protection and flotation. Not only are ammonites important for scientists, but they are aesthetically pleasing and a natural example of the famous mathematical Fibonacci sequence, or the “Golden Ratio.”
Devonian (~360 million years ago)
Alnif, Morocco