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Tiny plant-like organisms called zooxanthellae live in the tissues of many animals, including some corals , anemones, and jellyfish , sponges, flatworms, mollusks and foraminifera . These microscopic algae capture sunlight and convert it...
I have been at the Smithsonian’s National Museum of Natural History since 1966...
Collect, sort, identify, photograph, sample, record. Repeat a couple thousand...
Boring sponges get a bad rap. Their own name betrays them, announcing to the...

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How does a coral spend its day? Most of us would say: not doing much. To the human eye, a coral looks relatively still, waiting in the current and hoping some food will run into its tentacles. But this video "Slow Life" by marine...
The blue crab ( Callinectes sapidus ) is one of the most important...
Like this ctenophore ( Aulococtena acuminata ), many animals that live in...

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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...

The Ocean Blog

It is a well-known fact that for animals living in the deep sea, food can be scarce. The food that is around usually rains down from above as dead animals and organic particles from plankton living...
“The largest land migration of any animal on Earth, as many as 120 million crabs carpet the island in red as they move from the rain forest to the coast.” -- Nature's Best photographer, Stephen...
Weighing 600 pounds (around 272kg) and having a 30 foot (around 9 meters) arm span, the largest recorded giant pacific octopus was truly enormous. Giant pacific octopuses are powerful predators that...
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...
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 .
This brightly colored squat lobster collected in Moorea is a common find among the coral heads. Although called lobsters, this group of crustaceans is more closely related to hermit crabs than to...
The veined octopus ( Amphioctopus marginatus ), also known as the coconut octopus, has a skill beyond other cephalopods: it hides under animal and coconut shells, dragging them along the seafloor for...
Welcome to Citizens of the Sea , a new blog series where ocean life comes to life. Our book by the same name came out in September, but no sooner had it gone off to the printer than new ocean stories...
Glowing photophores are visible on this midwater squid ( Abralia veranyi ) viewed from below at low light levels. We think of light as a way to see in the dark. But many species use it to help them...
This new species of lobster is blind—an adaptation to deep-sea life —and has very bizarre claws, or chelipeds. It was discovered about 300 meters (984 feet) deep in the Philippine Sea by a Census of...
The jingle shell ( Anomia simplex ) is a common bivalve found on the Atlantic coast of North America, amongst the more commonly known clams and oysters. As with oysters, the lower shell is glued to a...
Giant clams are one of the many wonders of coral reefs. They can grow up to five feet wide, weigh over 400 pounds, and live for 100 years! They power all that bulk by filter feeding microbes and...
Some of the most otherworldly animals—like those straight from a science fiction story—can be seen in the open ocean at night. By drifting in the blackwater in a scuba suit just under the surface,...
With 1,400 named species of ribbon worms inhabiting every ecosystem on earth, seeking one out should be an easy proposition. But I quickly learned that it can be quite daunting when you’re looking...
This 200-year-old bamboo coral colony is growing on the Davidson Seamount off the coast of California. The skeleton of this deep-sea coral has bamboo-like segments. See more pictures of coral in our...
The yellow bioluminescent ring on this female octopus ( Bolitaena pygmaea ) may attract mates. Bioluminescence is an important adaptation that helps many deep sea animals survive in their dark world...
Nudibranchs are a kind of sea slug, and their 3000 species are found from the poles to the tropics in both shallow and deep water. Though they often only reach two centimeters in length, they are...
Smithsonian Zoologist Dr. Clyde Roper (rear) and museum specialist Mike Sweeney examine the mantle of a dead giant squid. Everything we know about giant squid comes from studying specimens found...
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