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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

Most wild seahorses (here the thorny seahorse Hippocampus histrix ) are monogamous and some species mate for life. Searching for mates can be difficult and risky since seahorses are poor swimmers,...
In 1874 Reverend Moses Harvey of Newfoundland displayed the giant squid he bought on the side of his barn, much to the dismay of Mrs. Harvey. More about the giant squid can be found in our Giant...
An isopod stands on top of a glass sponge, extending its legs to find zooplankton. This delicate sponge is small, but some glass sponges can grow to the size of a 50-gallon drum and live for...
About 100 million years ago , during the heyday of the dinosaurs, reefs were built by mollusks called rudist clams. Like modern clams, rudists were bivalves , with two shells (or valves) joined at a...
Dr. Clyde Roper prepares to dive thousands of feet to a giant squid habitat off the coast of New Zealand in a one-person submersible. More about the giant squid can be found in our Giant Squid...
This giant isopod (a crustacean related to shrimps and crabs) was collected from the cold, deep waters of the Gulf of Mexico in 2006. Scientists believe that it is one of about nine species in the...
Throughout their lifecycle, jellyfish take on two different body forms: medusa and polyps. Polyps can reproduce asexually by budding, while medusae spawn eggs and sperm to reproduce sexually. Learn...
A beroid ctenophore lunges toward prey with its mouth wide open. Beroid comb jellies don't have tentacles to catch prey: instead, they can open their mouths and snap them shut tight to trap prey...
Winner of the ‘best camouflage’ contest, the nudibranch Scyllaea pelagica (Scyllaeidae) is usually betrayed only by its motion. Along it’s back, the sea slug has growths called papillae that help its...
In 2006, this female giant squid attacked bait suspended beneath a Japanese research vessel off the coast of Japan in the Ogasawara Islands . This screenshot resulted when the research team pulled...
A pile of sea stars decomposing from starfish wasting syndrome on the coast of Vancouver in September 2013.
Ghost crabs are often seen scuttling quickly along beaches at night, when they emerge from their burrows to feed, and can be difficult to photograph in the wild. They are common in Moorea, an island...
Thalassinidean shrimp ( Thalassinidea ) build complex burrows deep in the mud. More about mangroves ecosystem can be found in our Mangroves featured story .
This male giant squid is on display in the Sant Ocean Hall at the Smithsonian’s National Museum of Natural History . It measures about 2.7 meters (9 feet) long and weighs a little more than 45.5...
Octopuses can change the texture and color of their skin to blend in with their surroundings. This day octopus ( Octopus cyanea ) has shaped itself like seagrass or some coral so hide from predators...
These watercolor sketches of Trapezia crabs were drawn by Frederick Bayer, a former Smithsonian coral biologist, in 1947. Trapezia crabs live on and within corals, feeding on their tissue and mucus,...
Boring sponges get a bad rap. Their own name betrays them, announcing to the world that they are unexciting, ordinary and quite frankly, boring. However, if ever a misnomer existed, this is it. More...
I have a vivid childhood memory of sitting under the Blue Whale model hanging in the Natural History Museum in London, eating an ice cream and wondering “How in the world did that whale get so big?”...
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