I heart diatoms.
Diatoms are single celled photosynthetic algae that are abundant in Earth’s lakes and oceans. These organisms create intricate nano-scale glass exoskeletons that protect their cellular interiors and focus specific wavelengths of light into photosynthetic protein complexes. Clusters of silica tubes on the surface form pores that are used to gather nutrients from the environment. The mechanism by which diatoms construct such beautiful symmetrical shells remains a mystery.
Image Credit: James Tyrwhitt-Drake, University of Victoria.