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Organ Pipe Coral
Photograph by Robert Sisson
The rocky structure that make up coral reefs are actually a build-up of calcium secreted by coral polyps.
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Pillar Coral
Photograph courtesy Florida Keys National Marine Sanctuary/NOAA
Coral polyps can reproduce asexually, forming cloned buds that separate from the "parent." They can also release sperm and eggs into the ocean. Fertilized eggs develop into larva, which float off to start a new colony.
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Pipe Coral
Photograph courtesy The Coral Kingdom Collection/NOAA
Corals get their vibrant colors from the algae they host.
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Cavernous Star Coral
Photograph courtesy Florida Keys National Marine Sanctuary/NOAA
Coral and sea anemones are in the same family of stinging invertebrates. This close-up of a cavernous star coral shows the individual polyps, which resemble tiny sea anemones.
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The Beauty of Insect Eggs
Engineered for survival, insect eggs hang on and hatch wherever their parents deposit them.
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Eels Photo Gallery
The freshwater eel is one of the few fishes to spawn in the ocean and spend its adulthood in lakes, rivers, and estuaries.
