Meet the “Walking Sharks:” They Amble on Land, Too.

 Walking sharks are only a small piece of our planet’s shark universe, but they’re remarkable for their ability to propel themselves along the seafloor using bodies and fins. And, actually, on land – literally fishes out of water. New walking shark research by an international team of scientists has found that, in terms of evolution, they are the most recent group of sharks to arrive on the scene. DESPITE A COMMON MISCONCEPTION, only a small number

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True Soft Corals: Beautiful, with an Identity Problem

True soft corals are among the most beautiful gems of the reef, yet they’re difficult to get a handle on etymologically. People insist on calling other stuff, like sea fans and mushroom corals, “soft corals.” Species in Family Nephtheidae deserve to be appreciated and understood by themselves.  TRUE SOFT CORALS ARE BEAUTEOUS TO BEHOLD AND DIFFICULT TO DEFINE. They’re beautiful in their delicate multi-branched structures, feathery clusters of polyps and striking pastel reds, yellows, blues,

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Seahorse Anatomy: Differences Way Beyond “Cute”

Seahorses are at once weird and wonderful, exotic and underwhelming and unique among bony fishes. Underneath their obvious horsey-head charm, seahorse anatomy is really, really different from other fishes. THE MOST OBVIOUS THING ABOUT SEAHORSES IS THEIR BODY DESIGN – an upright torso connecting a horse-shaped head and a monkey-like tail. They’re bony fishes, but pretty much the only bony fish that swims upright. When they swim. If searching for them carries an air of

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Whales & Carbon: To Save the World, Save the Whales

As the world ponders ways to capture carbon and combat climate change, think about the idea of whales and carbon storage. During their long lifetimes, great whales takes gargantually more carbon dioxide out of the atmosphere than whole forests of trees – and keep it there. A new study underscores our cetacean cousins’ importance to our planet beyond just oceanic diversity.  GREAT WHALES SWIMMING IN THE OCEANS DON’T SPRING TO MIND AS A SOLUTION TO

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How Fish Feed: For One Thing, They Suck It Up

If your idea of how fish feed on the reef is ferocious hunters swooping in to grab other fishy prey, you’re very unlikely to see that on most dives. But the 28,000 species of bony fishes in the world’s oceans make their livings in a myriad of ways – and they’re doing it all around you. IF YOU’RE SURPRISED AT HOW LITTLE FISH-ON-FISH FEEDING ACTION YOU ACTUALLY SEE WHILE YOU’RE UNDERWATER, a major reason is

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Video Sidebar: Fish Bottomfeeding Strategies

This is a video sidebar to a longer feature on “How Fish Feed.” Two minutes in length, it shows four types of fish bottomfeeding techniques to find and capture small crustaceans, mollusks and other invertebrates buried in the sand flats surrounding reefs.  WHEN YOU’RE TALKING ABOUT LOAN SHARKS AND SHADY LAWYERS, “bottom-feeding” is a disparaging term. But for lots of fish and other reef denizens, it’s a productive way of life. We may see a

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Bivalve Mollusks: Oysters & Scallops & Clams, Oh My!

ON THE REEF, OYSTERS, SCALLOPS, CLAMS AND MUSSELS ARE PRETTY MUCH THE INACTION FIGURES. Mostly, they just sit there. If you come close, they clam up, so to speak, until you go away. Yet, environmentally, economically and, yes, culinarily, they’re big players in the oceans and in our kitchens. Spoiler alert: The bivalve mollusks you’ll see on the reef are unlikely to be the ones seafood lovers salivate over. But, they’re likely to be more

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Bubble Coral: Soft On Top, Stony Underneath

With grape-sized, sac-like membranes, bubble corals look soft, squishy and egg-like from the outside. But underneath, Plerogyra sinuosa and its like are hard, stony corals. Although they’re popular with home aquarium enthusiasts, it’s somewhat of a find to spot bubble coral on the reef.  WHEN YOU COME ACROSS CLUSTERS OF BUBBLE CORAL, at first glance you might take them for large fish eggs, or perhaps errant egg clutches of some animal, say a cephalopod. Once

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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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