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Zombie worms don’t crave brains: instead they seek bones. The 1 to 3 inch (2 to 7 centimeter) Osedax worms were first discovered living in the bones of a rotting gray whale on the...
Marine parasites may be small in size, but they can be present in very high...
During the summer of 1998, scientists at the Virginia Institute of Marine...
The blanket octopus can rip a poisonous tentacle from a Portuguese man-o-war...

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Like this ctenophore ( Aulococtena acuminata ), many animals that live in the midwater zone are red—making them almost invisible in the dim blue light that filters down from the sea surface. This small comb jelly snares prey with...
Sponges are animals that eat tiny food particles as they pump water through...
Polarized sunglasses have become the norm for humans when they want to...

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Giant squid live up to their name: the largest giant squid ever recorded by scientists was almost 43 feet (13 meters) long,...

The Ocean Blog

In 2012, the long-elusive giant squid was finally filmed live in its natural habitat. The squid was found by placing glowing lures outside of a submersible to mimic jellyfish, which typically...
Several species of amphipod like this one, Gammarus wilkitzkii , live permanently within Arctic sea ice . These animals are endemic, meaning they only live here. They acclimate to a wide range of...
A specimen from the Smithsonian’s squid collection and videos of a mystery squid helped scientists identify a new family of deep sea squid—the Magnapinnidae, known as the bigfin squids. More about...
Hermit crabs, like this one collected in Moorea, usually protect their soft, vulnerable abdomens from predators by reusing empty snail shells. They are picky home owners and they will trade shells...
A mass of white muscle the size of a softball surrounds the dark brown beak of a giant squid. Learn more about this animal's oversized anatomy in our Giant Squid section .
During the 2012 field season of the Deep Reef Observation Project (DROP) in Curaçao, Smithsonian scientists collected many specimens with the help of the Curasub . Prospective new species were caught...
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...
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...
Seahorses are not just tropical creatures. They can be found in colder waters like those found off New Zealand, Argentina, Eastern Canada, and the UK. This long-snouted seahorse ( Hippocampus...
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 .
Last week, Smithsonian research zoologists Dr. Jerry Harasewych and Dr. Martha Nizinski were in Curaçao looking for deep-sea marine gastropods and decapod crustaceans , respectively. I learned they...
There are 47 different species of seahorses and 14 of those were discovered in the last eight years, including Pontoh's pygmy seahorse ( Hippocampus pontohi ), which was officially named in 2008...
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...
“This image was captured during an evening dive in water where the largest migration on Earth occurs nightly," said Nature's Best Photographer Joshua Lambus. The migration he speaks of is the diel...
Dr. Martha Nizinski holds a specimen of a fan sponge ( Phakellia sp. ) collected at a deep-sea coral study site off the coast of South Carolina. Deep-sea corals and sponges provide structure for a...
Sperm whales have conical teeth on their long, narrow, lower jaw. The teeth fit neatly into sockets in the upper jaw, which has no teeth. This arrangement is a perfect adaptation for slurping up soft...
A fringe of short tentacles surrounds the flattened bell of this tiny, transparent jellyfish ( Halicreas minimum ), which can be found at depths up to 984 feet (300 meters). But it would be hard to...
A deep-sea octopus wraps itself around a submersible’s robotic arm 2,300 meters (7,546 feet) down in the Gulf of Mexico. "Most octopuses will let you get close, maybe even touch them, but normally...
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