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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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“Upon returning from the reef after a night dive, I swam toward a bright reflection and came eye-to-eye with this beautiful, curious squid," said Charles Viggers, a Nature's Best photographer. Squids have organs in their skin...
This ctenophore (a stingless jellyfish-like animal) is native to the east...
This nudibranch has a few tricks up its sleeve: it steals jellyfish...

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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

Researchers in Moorea use a variety of tools to collect organisms. Some are simple, everyday items like buckets and brushes, and some are…a little stranger. Here, two researchers use a “yabbie pump”...
Many jellyfish in the class Hydrozoa, such as this hydromedusa Aglantha digitale , are transparent and easily overlooked. Learn more about hydrozoan jellies and other jellyfish , and see more...
Two bright orange anemonefish ( Amphiprion ocellaris ) poke their heads between anemone tentacles. Anemonefish are able to swim amongst the stinging tentacles without getting stung — but no one knows...
This swimming crab ( Liocarcinus holsatus ) has a parasitic barnacle rooted in its reproductive system. This invasion cuts off all reproduction for an infected crab and can even cause a male crab to...
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...
It's a pygmy seahorse ( Hippocampus bargibanti ), found in Indonesia's biodiverse Coral Triangle and one of the smallest seahorse species in the world! They can change colors like a chameleon to...
This beautiful larval (baby) octopus was collected by scientists from the University of Miami during a research cruise in the Straits of Florida, a narrow channel between the Atlantic and the Gulf of...
This venomous box jelly ( Chiropsalmus quadrumanus ) was collected off the coast of South Carolina. The specimen now resides in the Smithsonian’s marine collection . It's venomous sting can be lethal...
The “Hyperbolic Crochet Coral Reef,” a unique exhibition and thought-provoking fusion of science, conservation, mathematics, and art, is on display in Washington, D.C., at the Smithsonian’s National...
Marine parasites may be small in size, but they can be present in very high numbers and put together can weigh even more than all the top predators in an estuary or bay ecosystem! They play an...
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...
When hoping to discover a pearl, looking inside one of the oysters you slurp may not be the best plan. Food oysters in the family Ostreidae are able to produce pearls, however these tend to be small...
Giant squid have the largest eye in the animal kingdom. At up to 10 inches in diameter, people often describe it as the size of a dinner plate -- or, in other words, as big as a human head. Here,...
This orange boring sponge ( Cliona varians ) overgrows several coral species at Panama's Smithsonian Tropical Studies Institute. Boring sponges mechanically and chemically breakdown mollusk shells...
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...
Rapa whelks , native to Asia, have invaded the Chesapeake Bay and are raising concerns about economic and ecological impacts to the Bay region due to their shellfish diet. Scientists believe that...
Seahorses are the only fish species that can hold your hand! Unlike most fish that use their tails for swimming, seahorses, such as this longsnout seahorse ( Hippocampus reidi ), use their monkey-...
Humans have long been captivated by what we now call the giant squid ( Architeuthis ). This image gallery gives a glimpe into our fascination with the animal. For a long time, people saw mysterious...
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