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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

With a scientific name that means "the vampire squid from hell," you'd expect the vampire squid ( Vampyroteuthis infernalis ) to be a fearsome predator terrorizing the deep. Despite its demonic look...
Isopods (small, shrimp-like animals) like this one ( Gnathia aureusmaculosa ) are the mosquitoes of the sea, sucking the blood of fish while they sleep. Find out more in " No Fouling Around " from...
These baby olive ridleys ( Lepidochelys olivacea ) will eventually provide a home to crustaceans, mollusks, and other epibionts. That's according to a survey of epibionts living on mature, nesting...
Brachiopods are an ancient group of organisms, at least 600 millions years old. They might just look like clams, but they are not even closely related. Instead of being horizontally symmetrical along...
Found in Arctic waters, this rare deep-water species of larvacean , Oikopleura gorskyi , eats by filtering particles from the seawater it drifts through. Larvaceans build 'houses' around themselves...
A giant squid left this tentacle behind after getting entangled on a hook below a Japanese research vessel, and eventually escaping. An underwater camera took footage of the event—the first time a...
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...
The over 1,000 species of ribbon worms ( Nemertea ) are mostly found in marine environments (like the Hubrechtia found in a mud flat, in the photo). These worms have both a mouth and an anus (unlike...
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...
Portrait of a scallop with black and white striped lips, whose shell is encrusted with a red sponge.
Dead man’s fingers ( Alcyonium digitatum ) are soft corals named for their appendage-like appearance when thrown ashore by storms. The finger-like clumps of coral polyps come in various shades of...
This tan urchin, Conolampas sigsbei , is one of only two known deep-sea urchins that cover their tops with small rocks and shells. Many shallow species cover themselves for reasons that have been...
This bivalve mollusk is native to the Caspian Sea, lagoons of the Black Sea, and their inflowing rivers. It lives in fresh and brackish water and cannot tolerate full seawater. In the 18th and 19th...
Atolla tenella , a midwater scyphomedusa , as seen under a microscope. View the “Under Arctic Ice” photo essay to learn more.
Nine years ago I was invited by a colleague to join a research team investigating deep-sea coral habitats . I was asked to examine the invertebrates associated with these ecosystems. After my first...
All over the world, people have been witnessing gigantic blooms of tens of thousands of jellyfish where once there were only a few. Fishers find them clogging their nets and costing them dearly. In...
A sea monster attacks a ship in an illustration for 20,000 Leagues Under the Sea by Jules Verne. The illustration is by publisher and artist Pierre-Jules Hetzel, who is most famous for his drawings...
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...
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