Sea urchin test

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Empty shell (test) of a sea urchin in transient light. Clearly seen is the fivefold symmetry that is indigenous to all organisms in the phylum Echinodermata. The radiating spines that characterise live sea urchins are missing here, but the punctuated pattern is clearly suggestive of the way these spines were attached to the hard spherical shell. Actual diameter is 70 mm.

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Size: 5213px × 4594px
Location:
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, animal, background, biological, biology, black, circle, circular, echinoderm, echinodermata, echinoidea, empty, fauna, fivefold, fold, light, nature, pattern, punctuated, sea, shell, spherical, spines, symmetry, test, transient, urchin, zoological, zoology