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What reef animal comes in a rainbow of crazy colors, can throw out its stomach to immobilize predators, then creep away and regrow a brand-new stomach? It’s the sea cucumber, prized as a gastronomic...
This summer, many of you have likely enjoyed feasting on crabs, be they blue,...
About 100 million years ago , during the heyday of the dinosaurs, reefs were...
Zombie worms don’t crave brains: instead they seek bones. The 1 to 3 inch (2 to...

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The sea hare gets its common name from its equivalent of nose and tongue—external sensory organs for smell and taste called rhinophores—which look like bunny ears. The sea hare, however, doesn't hop like a rabbit: it is a sea...
“Upon returning from the reef after a night dive, I swam toward a bright...
This ctenophore (a stingless jellyfish-like animal) is native to the east...

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Sample the surprising diversity of deep-sea corals. See some of the ways they differ in color, shape, and size. Explore more...

The Ocean Blog

A blue cod and sea pens , a unique type of cnidarian , speckle the seafloor in New Zealand's Fiordland region.You can see more beautiful underwater photos from Brian Skerry in his image gallery .
A morning sun star ( Solaster dawsoni ) loses its grip on a rock surface as its body slowly decomposes from starfish wasting syndrome off the coast of Vancouver in September 2013. These photos are...
Zombie worms ( Osedax roseus ) eat away at the bones of a dead whale that has fallen to the seafloor in Sagami Bay, Japan. These bizarre worms rely on whale bones for energy and are what scientists...
Fitting nine of anything on two fingers is impressive. These mollusks and echinoderms are a teeny-tiny sample of the ocean's biodiversity. The Census of Marine Life estimates that there are at least...
This photo shows just a small part of the cephalopod collection at the Smithsonian's National Museum of Natural History. Shown here is Dr. Clyde Roper , a zoologist and squid expert. More about the...
Last September, the Citizens of the Sea blog series brought you a story of doom and gloom from the reefs of Bocas del Toro, Panama. That is the time of year we typically study -- and celebrate -- the...
Seahorse couples, such as this pair of thorny seahorses ( Hippocampus histrix ) , greet each other every morning with a unique dance that sometimes involves changing color. The couple promenades and...
This brilliant red octopus ( Benthoctopus sp. ) was photographed at more than 8,800 feet (about 2,700 meters) in Alaminos Canyon in the Gulf of Mexico. See more photos of wild creatures encountered...
An adult giant squid struggles for survival in an encounter with a sperm whale - its only known predator. The whale will probably overpower and eat the squid. More about the giant squid can be found...
The larger of two giant squids on display in the Smithsonian's Sant Ocean Hall , this female was caught in a fisherman's net off the coast of Spain in 2005. It was probably 2-3 years old and, when...
This newly-discovered carnivorous sponge ( Chondrocladia lyra ) was found using robotic submersibles operated by the Monterey Bay Aquarium Research Institute 10,000 feet below the surface in dark...
Tiny plant-like organisms called zooxanthellae live in the tissues of many animals, including some corals , anemones, and jellyfish , sponges, flatworms, mollusks and foraminifera . These microscopic...
These cancer cells have been treated with discodermolide, a chemical obtained from a sponge that grows on deep-sea coral reefs. It prevents the cells from dividing and spreading. Learn more about...
Amanda Feuerstein with a nesting olive ridley ( Lepidochelys olivacea ). Feuerstein is a co-author of a study that surveyed algae, crustaceans, mollusks, and other epibionts that live on olive ridley...
Shellfish from the Chesapeake Bay are prized by seafood lovers. But the Bay's ecosystem and fisheries are threatened by human disturbances, including the introduction of non-native species. Non-...
The Smithsonian's Department of Invertebrate Zoology has a collection of over 57,000 specimens from over 5,700 sites in the Gulf of Mexico, which are now catalogued on Google Earth . Below is a tiny...
Like octopods and cuttlefishes, giant squid have eight arms. But they use their two much longer feeding tentacles to seize prey. The tentacles have powerful suckers at the ends. More about the giant...
Giant clams are one of the many wonders of coral reefs. They can grow up to five feet wide, weigh over 400 pounds, and live for 100 years! They power all that bulk by filter feeding microbes and...
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