What is This? The Innards of a Daisy?

The hollow, cylindrical polyps of the coral Stylophora pistillata gather plankton with their tiny tentacles. Photosynthetic algae living within the polyps provide the coral with energy, its vibrant colors, and protection against the acidic byproducts of its respiration. Researchers from Monaco recently discovered the first gene in coral that adjusts its activity based on the time of day [subscription required]: it works twice as hard at night to neutralize acid that the sun-dependent algae cannot remove. Another coral gene responds to a full moon, triggering the simultaneous release of millions of eggs and sperm along a reef.