Braarudosphaera Bigelowii

Braarudosphaera bigelowii (Prymnesiophyceae) is a coastal coccolithophore with a long fossil record, extending back to the late Cretaceous (ca. 100 Ma).

Interesting, nature discovered the dodecahedron 40 million years before primates evolved, about the same time the bees emerged. Larger version of the image in the article linked above. 

Looks like it even knew about the "Golden Ratio"in its dividing of the edges of the pentagonal faces. :o)