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by Fox Meyer Squids, octopuses, and cuttlefishes are among the few animals in the world that can change the color of their skin in the blink of an eye. These cephalopods —a group of...
Watch as barnacles feed on bioluminescent dinoflagellates. Barnacles are...
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Depending on whom you talk to, jellyfish are either fascinating, a nuisance, a...
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The ocean is home to a phenomenal diversity of marine organisms. They have...

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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, found in low densities and rely...
The blue crab ( Callinectes sapidus ) is one of the most important...
How many animals swim in the sea? It's not easy to count them all. To get a...

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Jellyfish and comb jellies are gelatinous animals that drift through the ocean's water column around the world. They are...
These deep-sea photographs show a variety of broad-collared enteropneusts or acorn worms . These wormlike animals make spiral tracks on the sea floor. All the species shown here are new to science,...
A pile of sea stars decomposing from starfish wasting syndrome on the coast of Vancouver in September 2013.
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...
Another common species of sargassum shrimp, Leander tenuicornis (Palaemonidae) can be spotted by its long transparent claws or "chelae". Very similar shrimp are found in near shore habitats all...
Lanceola clausi , the bull-dog amphipod , another rare deep-water species captured below 1000 meters (3281 feet) with the multinet . View the “Under Arctic Ice” photo essay to learn more.
Not all slugs (snails without shells) are slimy brown pests found in your backyard garden. In the ocean they come in a huge variety of colors — some match the background and are hard to spot, but...
The ocean is home to a phenomenal diversity of marine organisms. They have evolved to inhabit warm waters near the equator and the icy waters of the Earth’s poles. Marine life takes advantage of the...
The giant squid is among the largest invertebrates on Earth, but this deep sea creature has rarely been observed by humans -- alive. Over the centuries, many dead giant squid have washed up on the...
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...
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...
Smithsonian Zoologist Dr. Clyde Roper , the world's foremost authority on giant squid, explores the squid collection at the National Museum of Natural History. He is passionate about giant squid and...
Comb jellies (such as this Bolinopsis species) are named for their combs: the rows of cilia lining their bodies that propel them through the ocean. Read more about jellyfish and comb jellies .
Sponges are animals that eat tiny food particles as they pump water through their bodies. They are very common on Caribbean coral reefs, and come in all shapes, sizes and colors. There is great...
Sea jellies such as this one in the genus Benthocodon are commonly seen on or near the seafloor in the Monterey Canyon off central California. Some jellies in this genus feed on animals that live in...
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,...
Tectitethya crypta (formerly known as Cryptotheca crypta ) is a large, shallow-water sponge found in the Caribbean. It was first studied for medical purposes in the 1950s when few scientists or...
This much smaller hyperiid (in the genus Paraphromina ) has eyes that make up 45 percent of its body! Its many retinas, which researchers believe are used to maximize light detection, are the small...
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