Photo of the Day

Layers of coral, sea fans, crinoids, and sponges make up a healthy reef off Indonesia's Tukangbesi Islands. Lighted by a photographer's strobe, this scene would explode in brilliant colors, but in natural light, it looks altogether different. Scientists are studying how wavelengths of light change at depth and how fish perceive these colors.

(Text adapted from and photo shot on assignment for, but not published in, "One Fish, Two Fish, Red Fish, Blue Fish: Why Are Coral Reefs So Colorful?" May 2005, National Geographic magazine)

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