A slideshow of the newest features on Poseidon’s Web – Explain the Reef!

Sharksuckers: Not Just for Sharks! And They Don’t Suck

More properly known as remoras, the “sharksuckers” that famously hitch rides on sharks also stick themselves to tunas, manta rays and other large fishes, turtles, whales, boats and anything else that might move. Including, occasionally, divers.   SHARKSUCKERS – REMORAS – USE LARGE SUCTION PADS on the tops of their heads to stick to their hosts, relying on those sharks, rays or whatever to do the heavy work of actually moving. The suction pads are transformed

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How Fish Breathe: Ram Ventilation, Buccal Pumping

FISH GOTTA SWIM…THEY ALSO GOTTA BREATHE. Or, more properly, they need to continuously restock their blood supply with oxygen from the surrounding water column to maintain the functions of living. Key to how fish breathe is the constant streaming of water past thin, permeable membranes in their gills that enable the diffusion of oxygen from the water into the blood stream. Fish maintain that flow of water by either of two methods – ram ventilation

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Manta Ray Socializing: Mantas Just Want to Hang Out

FAR FROM BEING FREE-RANGING LONERS, MANTA RAYS BOND WITH EACH OTHER in relationships that often last for extended periods, according to a five-year study of manta ray socializing in Indonesia. Some mantas form loosely connected groups to hang out with. Not surprisingly, like their human counterparts, female mantas form much tighter friendships with other females than males do among themselves. The males? Well, the boys’ groups were looser and they tend to cruise more. MANTA

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Woodsy Perhaps, But Mangrove Forests are Essential Parts of the Reef

THREE THINGS TO KNOW ABOUT MANGROVE FORESTS: 1) They aren’t swamps. They grow in shallow ocean waters along tropical coasts, surviving tidal fluctuations and thriving on the edge between land and sea.  2) Mangrove trees generate the freshwater they need for survival by using a variety of mechanisms to filter the salt out of the ocean water.  3) They’re essential parts of reef systems, key to the reef life. ABOVE AND BELOW    Above water,

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Squid Reproduction: Don’t Mess with Squid Eggs!

SOMETIMES, DURING DIVES, YOU ENCOUNTER THESE THINGS attached to the bottom. They’re squid eggs. Here’s a hint: Don’t Mess With Them! Remember Kirk Douglas battling the giant squid in 20,000 Leagues Under the Sea? It’s could be like that. Maybe. MAKING MORE SQUIDS Squid reproduction is a complex process that involves fertilization following the transfer of a male squid’s sperm – in the form of a single bundle called a spermataphore – into a female’s central

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Stomach-Everting, Arm-Regenerating Starfish Explained

BOTH LITTLE KIDS AND MARINE BIOLOGISTS KNOW STARFISH BY THEIR FIVE ARMS. The starfish anatomy that lurks underneath a starfish’s bumpy skin is another thing (To be clear, the biologists know sea star facts, the rest of us not so much). There are 1,500 to 2,000 species of starfish, or sea stars, found in oceans worldwide, in pretty much every depth and type of habitat. They’re all alike in general architecture but come in a myriad

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Barnacles at Work

BARNACLES HAVE BEEN DESCRIBED AS SHRIMP THAT STAND ON THEIR HEADS AND FLYFISH WITH THEIR FEET. Despite the hard mollusk-like shells they build, acorn and gooseneck barnacles are crustaceans, related to shrimps, crabs and lobsters. Look closely and you’ll see fine, feathery extensions constantly being flicked into the current from within those shells, like expert fishermen casting and recasting into a stream. The creatures within use these “cirri” – adapted leg-like appendages – to capture

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Nudibranch Colors: Awesome Defenses

WITH FLAMBOYANT SWAGGER, NUDIBRANCH COLORS CALL ATTENTION TO THEIR SLUGY TORSOS – and that’s the point. As beautiful as they are, nudibranchs’ bright markings are statements telling potential predators to leave them alone. In brief, nudibranch tissues tend to be foul-tasting, if not toxic. Nudibranch’s colors are warning signs to potential predators that they’ll regret attempts to dine out on their nudibranchy flesh. There are other nudibranch defenses in the mix, as well. Some have

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 Nematocysts & the Science of Sting

NEMATOCYSTS ARE OCEAN STINGERS’ SECRET WEAPONS. In fact, they are the stingers. The way in which nematocysts sting is a story of the sneaky, harpoon-like ordnance of Phylum Cnidaria – jellyfish, coral and gorgonian polyps, sea anemones, fire corals and hydroids. If you happen to touch a sea anemone, a sea plume or coral tentacles (which you shouldn’t do), you’re likely to not feel their sting. Actually, you’ve probably been stung, ineffectively. Those animals’ stingers

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To Define Plankton, Think: “Ocean Food Bank”

THE PLANKTON IS ONE OF THE KEYSTONES OF THE OCEAN FOOD CHAIN. In fact, it’s one of the most important elements of life in the sea. And, yet, every time I mention the word, seek to talk about plankton, discuss plankton, define plankton, I can hear eyes roll all across Planet Earth. True, plankton doesn’t have the same excitement attached to it as, say, a celebrity punching a shark on You-Know-What Week. On the other hand,

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