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Fever. Aching muscles. Coughing. Sniffling. It’s flu season . Have you had your shot? If so, thank a horseshoe crab. In fact, if you’ve been put on an IV, had a medical device implanted,...
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The open ocean is surprisingly barren to the naked eye. Every now and again you...
Dr. Clyde Roper discusses the fascinating anatomy of the giant squid (...
In this video Smithsonian research zoologist Dr. Martha Nizinski takes viewers...

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This octopod is sometimes called a “Dumbo” octopod because its fins resemble the ears of Disney’s Dumbo the elephant. The video was recorded in 2003 on the Mid-Atlantic Ridge by the Russian manned submersible MIR 2. More about...
Giant squid have the largest eye in the animal kingdom. At up to 10 inches...
“Lembeh Strait is a fantastic place to find species that have evolved to...

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Nudibranchs are a kind of sea slug, and their 3000 species are found from the poles to the tropics in both shallow and deep...
Collect, sort, identify, photograph, sample, record. Repeat a couple thousand times. This is what the students and researchers have been doing as the Indonesian Biodiversity Research Center (IBRC)...
Ochre seastars ( Pisaster ochraceus ) feed on invertebrates, such as coral and shellfish, like the mussels pictured here. The starfish forces open the shell with suction disks on the underside of its...
Each month, the Naked Oceans podcast invites a leading marine researcher to pick the "critter of the month" by asking: if you were a marine organism, which one would you be? This month, Dr. Nancy...
This crab ( Neolithodes sp. ) was collected on a NOAA/MAR-ECO cruise to the Mid-Atlantic Ridge in the summer of 2009. Its red color provides camouflage and protection from predators. Red wavelengths...
A male mudflat fiddler crab ( Uca rapax ) waves its huge claw to impress females and threaten competitors. Only the males have the large claw. When the tide is high, fiddler crabs retreat to their...
Stinging cells (nematocysts) line the tentacles of this moon jelly ( Aurelia aurita ). Upon contact with prey or a predator, a venom-laden harpoon shoots out to stun or kill. Read more about...
A fan-shaped colony of red coral ( Corallium sp.) on the Davidson Seamount provides a perch for three basket stars as they feed. See more pictures of coral in our Deep-sea Corals article.
Sample the surprising diversity of deep-sea corals. See some of the ways they differ in color, shape, and size. Explore more in the multimedia feature " Coral Gardens of the Deep Sea ."
This forest of Christmas tree worms is a group of polychaete worms that live on tropical coral reefs. See more celebratory ocean creatures in our slideshow!
Flower-like clusters of polyps make up this coral colony. Their pink color comes from the zooxanthellae living inside. More about coral reef ecosystems can be found in our Coral Reefs featured story .
Deep sea animals have to live in a very cold, dark, and high-pressure environment where they can't see a thing! To survive there, they've evolved some very strange adapations. Some make their own...
“It is strange to think of a sea turtle as an ecosystem,” says Amanda Feuerstein, program coordinator and research assistant at the Smithsonian’s National Museum of Natural History, “but they are…...
In 1954 Smithsonian researchers dissected this squid specimen from the stomach of a lancetfish and added it to the Museum’s squid collection. Almost 50 years later, it helped scientists identify a...
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...
The Japanese spider crab is a large catch for any fisherman. With a leg span of 13 feet (4 meters) and an average weight of around 40 pounds (16-20 kg), it claims the title of largest crab. It may...
As it clings to a red sea fan, a feather star ( Cenometra bella ) gently waves its slender arms—filtering bits of food from the water. Also known as sea lilies, feather stars are related to sea stars...
This female hyperiid ( Phronima sedentaria ) is surrounded by her young, residing in the hollowed out barrel-shaped body cavity of a salp. It is thought that the mother Phronima captures and kills...
This rare staurozoan , or stalked jellyfish ( Haliclystus californiensis ) is about 2 centimeters in length and was collected off the coast of California. Unlike the traditional bell-shaped floating...
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