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This nudibranch has a few tricks up its sleeve: it steals jellyfish tentacles to use as weapons again its own enemies. How does it do this? Many fleshy, tentacle-like growths, called cerata (singular...
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...
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...
Stinging cells (nematocysts) line the tentacles of this moon jelly ( Aurelia aurita ). Upon contact with prey or a predator, a venom-laden harpoon shoots out to stun or kill. Read more about...
One of the first signs of a sick coral reef is seaweed creeping across the corals, stealing their precious sunny real estate. Healthy corals, however, aren't completely hopeless: in some reefs, small...
Anemone porcelain crabs may look delicate but they have their own sort of armor: a hard exoskeleton. They live under rocks, sponges, groups of feather stars, and even in giant anemones where they can...
You may have seen the sparkle of fireflies on a summer’s night. The fireflies produce light through a chemical reaction in their glowing abdomens, a process known as bioluminescence. But did you know...
The ROV Hyper Dolphin caught this deep-sea jelly (Atolla wyvillei) on film east of Izu-Oshina Island, Japan. When attacked, it uses bioluminescence to "scream" for help—an amazing light show known as...
This bait ball shows how small fish can react when larger predators are near by gathering tightly together in a ball-like formation that exposes the least number of fish. Fish species found in the...
Is that fruit swimming in the ocean? Well it may look like fruit, but it's actually a pineapplefish ( Cleidopus gloriamaris ). Like the hard outer part of a pineapple, this fish also has an outer...
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 mollusks with...
When most people think of catfish, they think of a freshwater fish. But the striped eel catfish ( Plotosus lineatus ) is found in marine systems including coral reefs, estuaries, tide pools and other...
These beautiful mandarinfish ( Synchiropus splendidus ) are covered in bright blue, red, yellow and orange waves. What they lack, however, are traditional fish scales. They live in western Pacific...
Beluga whales are naturally vocal animals. They are often called “ canaries of the sea ” thanks to their wide repertoire of sounds such as whistles, squeals, moos, chirps, and clicks. Some...
This crab ( Neolithodes sp. ) was collected on a NOAA/MAR-ECO cruise to the Mid-Atlantic Ridge in the summer of 2009. Its red color provides camouflage and protection from predators. Red wavelengths...
Most scuba divers scour coral reefs looking for colorful fish, natural beauty, and maybe even the perfect underwater photo . Shirley Pomponi , a biologist at Florida Atlantic University's Harbor...
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...
An octopus shoots ink in defense as it swims away from a scuba diver.
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