The Bahamas. You drop off the side of a small boat in clear tropical waters and swim over a lightly current-rippled bright sand bottom, spotted with brown patches of microalgae. You pass over a dark patch of seagrass, the blades bending slightly in the gentle current. Next a bare patch, and then the bottom rises up a meter and you are over multicolored corals and algae, with intricate branchings and textures. Idyllic and complex.

Mazel, C.H. 2001. Optics of the sea floor. Oceanography 14(3):54–63, https://doi.org/10.5670/oceanog.2001.23.

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