Sea angels are majestic sea slugs that use wings to propel themselves перевод

The Truth About Sea Angels

Don’t let these creatures’ angelic looks fool you

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Sailors have long reported sights of heavenly creatures swimming just below the water’s surface. They might not have been able to catch glimpses while peering over the rails of their ship, but they were right about one thing: there are sea angels lurking in the oceans.

Sea angels are in the clade Gymnosomata and are teeny tiny sea slugs that can measure up to only seven centimeters in length at most. They get their name from their wing-like appendages which help them glide around their ocean home.

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Sea angels are truly captivating to watch. Part of their overall allure can be attributed to the way they move. These creatures glide through the ocean in pulsing motions as graceful as a choreographed dance. The other thing that makes them so mesmerizing to watch is the fact that these animals are semi-transparent. Just by looking at them, you can see their internal organs and gonads! You don’t need a magic school bus to look deeper into a sea angel’s inner workings. You can see right through these incredible creatures and visualize what makes them tick.

There is a long list of things that make sea angels amazing. They are hermaphrodites, meaning they can switch sexes. Their mating rituals look a lot like a dance—which is every middle school dance chaperone’s worst nightmare—but it’s actually quite lovely to watch. A sea angel couple stays locked together during these rituals, spinning for hours while listening to the symphony of the ocean’s depths.

Yes, I did just lure you into a false sense of security about sea angels. Here’s the turn in the story, the moment the scary music begins to play and we descend into the deep dark secrets of these beautiful sea angels.

You see, sea angels are actually carnivorous, and they feed exclusively on the equally adorable-looking sea butterflies. Just like horror movie villains, different sea angels have different strategies when it comes to killing their prey. Some like to wait for the perfect moment to ambush; others actively hunt down poor sea butterflies before they eat them. Incredibly, sea angels move twice as fast as their prey, making it easy for them to move in for the kill.

Once they catch their unfortunate meal, the real horror show begins. Sea angels open their mouths and roll out special tentacle-like appendages known as buccal cones. Unlike sea angels, sea butterflies don’t lose their shells. Thus, these buccal cones have numerous hooks and teeth-like radula that allow them to scoop the sea butterfly out of a shell and into its gullet.

Take a moment to picture this with me. Imagine you’re about to be killed by a ruthless murderer in a horror movie, which is obviously bad enough. This murderer also has transparent skin, so you can literally see its heart beating as it goes in for the kill (yep, even scarier). Then, they take off their mask to reveal a bunch of flailing tentacles with sharp edges designed to scoop out your gooey bits like an avocado from its shell. Yes, we agree: it’s truly terrifying.

Oh … and remember that bit about sea angels’ beautiful mating dance? Well, I did leave a pretty important part out in my description. When mating sea angels get close to a mate, they actually turn their reproductive organs inside out. These critters have special suction cups that hold them together, leaving them literally scarred from the entire experience. Oh, and sometimes they will hunt at the same time as mating. Double the terrifying horror creature murdering you with razor tentacles, double the … fun?

Like every good supervillain, sea angels also make it quite difficult to be killed. Some species produce a chemical defense to deter fish from eating them. This trait has even earned them a henchman! The partners in crime—little crustaceans called amphipods—will attach themselves to these sea angels to take advantage of their superior defenses.

While their behavior might be terrifying, they have reason to be afraid of us as well. Human-induced ocean acidification is directly threatening sea butterflies, which means sea angels are quite literally losing their lunch. The shell of a sea butterfly is very thin, which means it can be dissolved in overly acidic seawater. The good news? You can take action on ocean acidification today to keep sea butterflies and the terrifying and wonderful sea angels alive and healthy for millions of years to come. Don’t wait: take action today for these jaw-dropping creatures.

Your gift can help save our ocean

Our ocean faces many threats like the onslaught of ocean trash, overfishing and ocean acidification. With the help of donors like you, Ocean Conservancy is developing innovative solutions to save our ocean.

“The Deep Sea”: life in the depth of the oceans

Young software developer Neal Agarwal (Twitter: @nealagarwal) created an amazing interactive visualization showing life in the depth of the oceans. Named “The Deep Sea” (click here to see the visualization), the interactive webpage shows the living depths and also the maximum diving points of various animals. Be prepared to be amazed!

The deep sea: living and/or dive depths of some animals and plants

Please keep in mind that the animals and plants listed below are not the only lifeforms to live in these depths – they are just a few examples.

Up to 14 meters (46 feet) deep

Atlantic salmon, Manatee (large, fully aquatic, mostly herbivorous marine mammals also known as sea cows), striped bass, staghorn coral

Up to 40 meters (131 feet) deep

Polar bear, European pilchard, barramundi (Asian sea bass), clownfish

Up to 66 meters (217 feet) deep

Velvet crab, blue tang, Atlantic cod, spiny dogfish, leafy sea dragon, mahi-mahi (or common dolphinfish, a surface-dwelling ray-finned fish found in off-shore temperate, tropical, and subtropical waters worldwide)

Up to 92 meters (302 feet) deep

Flounder (a group of flatfish species), spotted bass, beluga whale, bluefish

Up to 127 meters (417 feet) deep

Great barracuda, killer whale, queen snapper, pelagic stingray

Up to 170 meters (558 feet) deep

Sealion, leptoseris, bull shark, black drum, green sea turtle

Up to 200 meters (650 feet) deep

Atlantic mackerel, dentex

Ocean twilight zone begins

The ocean twilight zone lies 200 to 1,000 meters (about 650 to 3,300 feet) below the ocean surface, just beyond the reach of sunlight.

Also known as the midwater or mesopelagic, the twilight zone is cold and its light is dim, but with flashes of bioluminescence (light produced by living organisms). The region teems with life. Recent studies suggest that the biomass of fish in the twilight zone maybe ten times greater than previously thought, more than in all the rest of the ocean combined.

Up to 240 meters (558 feet) deep

Thick-billed murre dive, haddock, wolf eel (a species of wolffish from the North Pacific), chain catshark

Up to 275 meters (902 feet) deep

Kelp, terrible claw lobster, olive ridley sea turtle, great white shark

Up to 310 meters (1,017 feet) deep

Up to 332 meters (1,090 feet) deep

Gummy shark, human dive

At 332.35 meters, this is the deepest any human has scuba-dived. Set in 2014 by Ahmed Gabr (born 9 November 1972), an Egyptian scuba diver. As of December 2019, Gabr holds the Guinness World Records for both The Deepest Scuba Dive (Male) and The Deepest Scuba Dive in Sea Water. Ahmed dived to a depth of 332.35 meters (1,090.4 ft).

Up to 400 meters (1,312 feet) deep

Blue shark, firefly squid

Up to 450 meters (1,476 feet) deep

Up to 500 meters (1,640 feet) deep

Sea angel, chinook salmon, mako shark

Up to 550 meters (1,804 feet) deep

Up to 600 meters (1,969 feet) deep

Up to 650 meters (2,133 feet) deep

Bamboo coral, Japanese spider crab (the largest known crab with a leg span of up to 3.8 meters / 12 feet 5.61 inches)

Up to 700 meters (2,297 feet) deep

But, on December 23, 1938, a living specimen was found off the east coast of South Africa, off the Chalumna River (now Tyolomnqa). Between 1938 and 1975, 84 specimens were caught and recorded.

Up to 750 meters (2,461 feet) deep

Up to 800 meters (2,625 feet) deep

Giant pacific octopus, giant oarfish (the longest bony fish on Earth, although they commonly measured up to 3 meters/9.8 feet in total length, they can grow a record length of 11 meters/36 feet)

Up to 850 meters (2,789 feet) deep

Monkfish, Pacific cod

Up to 900 meters (2,953 feet) deep

Marrus orthocanna, vigtorniella worm

Up to 950 meters (3,117 feet) deep

Sperm whale dive, leatherback sea turtle

Up to 1000 meters (3,281 feet) deep

Baird’s beaked whale, also known as the four-toothed whale

Ocean midnight zone begins

The ocean’s midnight zone, also known as the Bathyal zone is a region between one and four kilometers (3,281 to 13,100 feet) deep, where no sunlight at all penetrates the frigid water. With no light, there is no growth of plants or phytoplankton (because of the lack of sunlight necessary for photosynthesis) – all animals are thus predators or scavengers.

Because of the lack of light, some species do not have eyes. Many deep-sea creatures cope by creating light themselves – also known as bioluminescence.

Up to 1,100 meters (3,609 feet) deep

Anglerfish (which have a large bioluminescent lure used to attract prey in the darkness), phronima, orange roughy (which is notable for its extraordinary lifespan, attaining over 200 years, one of the longest-living animals in the world. Deep-sea life often have elongated life spans.)

Up to 1,200 meters (3,937 feet) deep

Blobfish, the frilled shark, great white shark.

Up to 1,300 meters (4,265 feet) deep

Goblin shark – they sometimes called a “living fossil”, it is the only extant representative of the family Mitsukurinidae, a lineage some 125 million years old.

Up to 1,400 meters (4,593 feet) deep

Bubblegum coral, hatchet fish

Up to 1,500 meters (4,921 feet) deep

Dragonfish, big red jellyfish (many deep-sea species use the color red as camouflage since it is the first color to leave the spectrum as you dive deeper)

Up to 1,600 meters (5,249 feet) deep

Greenland halibut, giant tube worm ( giant tube worms get their nutrients from hydrothermal vents which are formed from seawater passing through extremely hot volcanic rocks. Hydrothermal vents release that are toxic to most animals, but giant tube worms can tolerate extremely high hydrogen sulfide levels.)

Up to 1,800 meters (5,906 feet) deep

Yeti crab, sixgill shark, narwhal dive (a medium-sized toothed whale that possesses a large “tusk” from a protruding canine tooth)

Up to 2,000 meters (6,562 feet) deep

Jewel squid, sea pen, telescope octopus (it is transparent, almost colorless, and has 8 arms. It is the only octopus to have tubular eyes, hence the reason it is commonly referred to as telescope octopus), Mobula ray.

Up to 2,200 meters (7,217 feet) deep

Giant isopod (meals are scarce in the deep-sea, so many deep-sea creatures are adapted to long periods of famine – one giant isopod has been known to survive over 5 years without food in captivity), Greenland shark, colossal squid (largest known squid species, they can grow up to 10 meters / 33 feet, and weigh up to 700 kg / 1.543 lbs)

Up to 2,400 meters (7,874 feet) deep

Barreleye fish, elephant seal dive

Up to 2,600 meters (8,530 feet) deep

Up to 2,800 meters (9,186 feet) deep

Squidworm, black swallower, viperfish

Up to 3,000 meters (9,843 feet) deep

Scaly-foot snail, vampire squid, headless chicken fish (Enypniastes, also known as the “swimming sea cucumber”), zombie worm, Cuvier’s beaked whale dive – the deepest diving mammal

Up to 3,200 meters (10,500 feet) deep

Glass sponge, gulper eel (also known as the pelican eel, a deep-sea fish rarely seen by humans), cosmic jellyfish, spotlight loosejaw (Malacosteus)

Up to 3,400 meters (11,155 feet) deep

Harp sponge, cookiecutter shark (it is named after the cookie-shaped wounds that it leaves on the bodies of its prey. This small fish is also known as the cigar shark because of its body shape)

Up to 3,600 meters (11,811 feet) deep

Lizardfish, flabby whalefish

The average depth of the ocean

3,688 meters (12,100 feet): the average depth of the ocean (according to NOAA, some sources, for example, National Geographic give a slightly different number)

Titanic’s resting deep

The wreck of the RMS Titanic lies at a depth of about 3,800 meters (12,500 feet).

Up to 4,000 meters (13,123 feet) deep

Patagonian toothfish (have antifreeze proteins in its tissues to prevent freezing in sub-zero temperatures), the dumbo octopus

Abyssal zone begins

The abyssal zone is the portion of the ocean deeper than about 4,000 meters (13,123 feet) and shallower than about 6,000 meters (20,000 feet). The zone is defined mainly by its extremely uniform environmental conditions, as reflected in the distinct life forms inhabiting it.

The temperature here is near freezing and very few animals can survive the extreme pressure.

“Abyss” derives from the Greek word “ἄβυσσος”, meaning “bottomless sea.”

Some sources start the abyssal zone from 2,000 meters (6,600 feet) and others from 3,000 meters (9,850 feet).

Up to 4,050 meters (13,287 feet) deep

Up to 4,600 meters (15,092 feet) deep

Sea pig, megamouth shark (it is one of the largest shark species with some reaching 8 meters / 26 feet long)

Up to 4,700 meters (15,420 feet) deep

Up to 4,800 meters (15,748 feet) deep

Fangtooth, tripod fish

Up to 5,000 meters (16,404 feet) deep

Up to 5,100 meters (16,732 feet) deep

Up to 5,300 meters (17,388 feet) deep

Up to 5,500 meters (18,044 feet) deep

Up to 5,600 meters (18,373 feet) deep

Abyssal spider fish

The Hadal Zone begins

The hadal zone (named after the realm of Hades, the underworld in Greek mythology), also known as the hadopelagic zone, is the deepest region of the ocean lying within oceanic trenches. The hadal zone is found from a depth of around 6,000 to 11,000 meters (20,000 to 36,000 feet).

Deep-sea trenches form by a process called “subduction” where the Earth’s tectonic plates meet and push together. Life here is sparse – the extreme conditions make survival difficult, but still not impossible.

So little is known about life in these deep environments. Almost every expedition uncovers something new.

USS Johnston (DD-557) shipwreck – the deepest shipwreck ever found

The USS Johnston sunk in WWII. Its wreck was discovered on October 30, 2019, what is believed to be the deepest shipwreck ever located at 6,220 meters (20,406) deep in the Philippine Trench.

Up to 6,800 meters (22,310 feet) deep

Up to 6,900 meters (22,638 feet) deep

Up to 7,200 meters (23,622 feet) deep

Comby jelly – they have been around for 500 million years. Despite looking like jellyfish, they are not closely related.

Up to 8,200 meters (26,903 feet) deep

Up to 8,400 meters (27,559 feet) deep

The height of Mount Everest

So far, you have scrolled the height of Mount Everest (8,848 meters / 29,029 feet).

Up to 10,300 meters (33,793 feet) deep

Mariana trench – the deepest point of the Earth’s oceans

On January 23, 1960, about 9 years before the moon landing, humans went where they never had before.

The Swiss oceanographer and engineer Jacques Piccard (28 July 1922 – 1 November 2008) and the American oceanographer, explorer and marine policy specialist Don Walsh (born November 2, 1931) reached the floor of the Mariana Trench (the Challenger Deep) using a special submarine named Trieste.

The submarine used a re-breather system that would later be used in spacecraft. There was barely enough space inside the pressure sphere for both of them.

The descent progressed without incident until 9,150 meters (30,000 feet), when the crew heard a loud crack that shook the entire vessel. They had no idea what it was.

Even at these unfathomable depths, Jacques and Don could still see life out the window. Life can survive in unimaginable environments.

The immense pressure of the deep sea means any mistake would mean certain death. They continued the dive, however, and after 4 hours and 47 minutes of anxiety and claustrophobia, they finally touched down in “snuff-colored ooze” at 10,916 meters (35,813 feet).

On March 26, 2012, Canadian film director James Cameron (born August 16, 1954) has reached the bottom of the Mariana Trench in the submersible vessel Deepsea Challenger. He became the first person to do this in a solo descent and is only the third person to do so ever.

The depth of the descent was measured at 10,916 meters (35,813 feet); later, more accurate, measurements during 1995 found the Mariana Trench to be slightly less deep at 10,911 meters (35,797 feet).

Data suggests that microbial life forms thrive within the trench.

This Website Lets You to Scroll to the Bottom of the Ocean and Discover Deep Sea Animal Life

There are 409,543 named species in the ocean, but the deep sea is home to a vast amount of mysterious creatures that are yet to be discovered. Inspired by marine life, Computer scientist Neal Agarwal has developed a fun website (titled The Deep Sea) that allows users to scroll down to discover the different animals and plant life that live at varying depths of the ocean.

As users move towards the bottom of the ocean floor, they are fed various facts and figures about marine life. Close to the ocean surface, at around 30 meters deep (98 feet), familiar fish such as the Atlantic salmon and the striped bass are seen, alongside the polar bear, who is known to dive to similar depths in order to hunt for food. Scrolling deeper reveals the killer whale at around 100 meters deep (328 feet), and the green sea turtle at around 170 meters (557 feet).

However, if you scroll even further, things start to become a little more interesting. The site marks the deepest depths that any human has ever scuba dived at 332 meters (1,089 feet), and it’s surprising to see that the emperior penguin can dive even lower, at 530 meters (1,738 feet). Once you get to the “Midnight Zone” at 1,024 meters deep (3,360 feet), you’ll meet the many deep-sea creatures that create bioluminescent light, such as the strange anglerfish and the infamous blobfish. One of the most suprising facts the website reveals, is that the giant elephant seal explores depths far below where these deep-sea creatures lurk, with dives that can reach 2,400 meters (7,874 feet) below the sea’s surface.

The Deep Sea website also reveals the resting places of famous shipwrecks, including the Titanic (3,800 meters / 12,467 feet) and the USS Johnston shipwreck that sunk in World War II and is the deepest wreck ever found (6,241 meters / 20,475 feet). And despite the extreme conditions at the lowest trenches of the ocean, there are still small signs of life—and there’s so much more to be discovered!

Meet the 50 Weirdest Deep Sea Creatures Lurking Beneath the Waves

These are the most bizarre aliens—err, animals—in the ocean.

Scientists know more about space than the ocean, according to Columbia University’s Earth Institute. So in a sense, a majority of the creatures lurking below the surface may as well be aliens. Meanwhile, researchers from Dalhousie University in Nova Scotia, Canada believe that 91 percent of these marine animals are still unknown to us.

🐙You like incredible marine creatures. So do we. Let’s nerd out over them together.

Of the 235,000 or so species we do know about, many have adapted to their environment with peculiar camouflage, bioluminescence, and mating habits—leading to some seriously strange appearances. These are our 50 favorite deep sea creatures.

More from Popular Mechanics:

Found in the Indian and tropical western Pacific oceans, the peacock mantis shrimp is a candy-colored crustacean known for its ability to quickly «punch» prey with its front two appendages. According to Oceana, the international ocean preservation advocacy group, this shrimp’s punch is one of the fastest movements in the animal kingdom—so much so, that it’s strong enough to break an aquarium’s glass wall. But no worries: They mostly only use their fists of steel to break open mollusks and dismember crabs.

Its name makes it sound like a piece of sexy lingerie, but don’t be fooled: the pink see-through fantasia is a sea cucumber, found about 1.5 miles deep into the Celebes Sea in the western Pacific, east of Borneo. It was only discovered a little over a decade ago, back in 2007, but the curious sea cucumber has a survival tactic that points to its longtime evolution: bioluminescence to ward off predators. The pink see-through fantasia is named for its transparent skin, through which its mouth, anus, and intestines are all visible.

It’s so easy to miss the frogfish, because these types of anglerfish (there are over 50 species of them) are nearly identical to their surroundings—mostly coral reefs. They resemble sponges or algae-covered rocks and come in pretty much every color and texture imaginable. Some frogfish even use their camouflage not to hide, but rather, to mimic poison sea slugs. No matter their appearance, one thing all species of frogfish have in common is their strange mode of locomotion. Although they can swim, most walk along their pectoral fins, which have evolved into arm-like limbs, including a joint that resembles an elbow.

The frilled shark, Chlamydoselachus anguineus, is one of the gnarliest looking creatures in the sea. If it looks like an ancient beast, that’s because it is: the prehistoric creature’s roots go back 80 million years. The frilled shark can grow to about seven feet long and is named for the frilly appearance of its gills. Although shark in name, these animals swim in a distinctly serpentine fashion, much like an eel. They mostly feed on squid, usually swallowing their prey whole.

Scientists found this strange creature at the Great Barrier Reef’s Lizard Island and named it, aptly, the Christmas tree worm. The spiral «branches» are actually the worm’s breathing and feeding apparatuses, while the worm itself lives in a tube. These tree-like crowns are covered in hair-like appendages called radioles. These are used for breathing and catching prey, but they can be withdrawn if the Christmas tree worm feels threatened.

Like so many other sea creatures, the box crab is a master of disguise. In this case, the crustacean—which mostly keeps to the seabed—buries itself beneath the sand, with just its eyes protruding from the mucky depths. One of the most fascinating aspects of the box crab’s life cycle is its mating habits, which literally redefine what it means to be swept off your feet. When the male box crab has found its mate, it grasps onto her with its claws and carries her around the sea floor until she molts her shell.

Researchers with the Census of Marine Zooplankton first discovered the squidworm in 2007 during a cruise in a remotely operated vehicle some 1.8 miles underwater. The funky-looking fish is named for the 10 appendages protruding from its head, which look like tentacles. The squidworm uses these to collect debris falling from the open waters above, known as «marine snow.»

These guys are native to chilly, deep waters and can grow to be quite large; in 2010, a remotely operated underwater vehicle discovered a giant isopod measuring 2.5 feet. These crustaceans, which sort of resemble a massive woodworm, are carnivores and usually feed on dead animals that fall down from the ocean’s surface. Despite their discovery back in 1879, these creatures mostly remain a mystery. However, it’s believed that giant isopods grow so large in order to withstand the pressure at the bottom of the sea.

With over 3,000 different species on record, the nudibranch is an extremely versatile kind of sea slug. These little guys are found pretty much everywhere, in both shallow and deep waters, from the North and South poles and into the tropics. There are two distinct kinds: dorid nudibranchs, which are smooth with feather-like gills on their back to help them breathe; and aeolid nudibranchs, which breath through a different kind of organ, also located on their backs, called cerata. Because the tiny nudibranch lacks a shell, it instead protects itself with bright camouflage, meant as a warning signal. But perhaps their wildest adaptation of all is the ability to quite literally swallow, digest, and reuse stinging cells from prey.

Although they’re called sea angels, these creatures are actually predatory sea snails. This particular specimen, Platybrachium antarcticum, «flies through the deep Antarctic waters hunting the shelled pteropods (another type of snail) on which it feeds,» according to the Marine Census of Life. Sea angels have special parapodia, or lateral extensions of the foot, that help to propel them through the water.

The gulper eel (also referred to as the pelican eel) is named for its massive mouth and jaw, which helps them to swallow prey whole. They can grow up to six feet in length and their huge mouths allow them to hunt down meals that are larger than them. This usually happens when food is scarce—it’s believed that gulper eels usually eat crustaceans and other small marine animals.

Like a multi-stage rocket, this bizarre microscopic creature, Marrus orthocanna is made up of multiple repeated units, including tentacles and multiple stomachs. Technically, they are physonect siphonophores, which are related to the Portugese man o’war. Like ants, a colony made up of many individuals has attributes resembling a single organism.

The Giant Squid, Architeuthis dux, is absolutely the stuff of nightmares. The largest one ever recorded came in at a whopping 43 feet long—nearly half the size of a blue whale. Earlier this year, scientists created a draft genome sequence for the giant squid, in a bid to better understand it. With about 2.7 billion DNA base pairs, its genome is about 90 percent the size of the human genome. Beyond that, scientists don’t know a whole lot about the giant beast or its habits, because most of what we know comes from their carcasses, which wash up on the shore. Most of the time, the giant squid lives in waters so deep that we never see them, adding to their intrigue.

A virus? An alien? Nope. It’s a Munnopsis isopod crustacean, and even scientists haven’t figured out more than that about this deep Southern Ocean denizen, yet. Isopods are ancient creatures (they’ve been on Earth, in one form or another, for 300 million years or so) with no backbones that have seven pairs of legs. On land, you might be familiar with their cousin, the pill bug.

This bizarre-looking fish is also known as the Galapagos batfish and can be found at the bottom of the ocean. It’s named for its red lips, which make it appear to be wearing lipstick. Although the red-lipped batfish appears to have legs, its limb-like appendages are actually fins, which the creature uses to stand on and to check out its surroundings.

There’s no other snail in the world armored like the Crysomallon squamiferum, which lives over hydrothermal vents deep in the Indian Ocean. It goes by quite a few other names, including the «scaly-foot gastropod,» «scaly-foot snail,» and even the «sea pangolin.» Today, its multilayered shell structure is inspiring stronger materials, from airplane hulls to military equipment.

One of the few known octopods known to use bioluminescence (or glowing with its own light), the Stauroteuthis syrtensis octopus lives about one mile deep in the Gulf of Maine. It can position its photophores (light-emitting organs) to fool prey into swimming right into its mouth.

With a name like flamingo tongue snail, and the flamboyant coloration to match, you might think this Cyphoma gibbosum has a shell worthy of collecting. Not so. All of the flamingo tongue snail’s color comes from the soft parts of its body, which envelop its shell. When threatened, it can retract its mantle flaps, exposing its true shell.

Strangely enough, this form of sea life is neither a squid, nor an octopus, despite its appearance. Scientists have designated the vampire squid as a completely separate animal, even though it has eight arms and two tentacles. Again, the name can be confounding—these creatures don’t suck blood and actually are pretty passive hunters, considering they’re filter feeders. Instead, the name comes from the skin between its arms, which resembles a cape. Oh yeah, and this little dude lives in the pitch black waters of the mesopelagic zone.

Also known as «the sea toad,» these deepwater fishes are relatives of the frogfish (see slide 3). These creatures have a small lure, protruding from a depression behind their eyes. Coffinfish use it to lure prey toward them, and because there is so little light at the depths where they live, it allows them to quickly attack. According to Smithsonian Magazine, these fish also «boast such sizable gills that they can increase their body volume by up to 30 percent upon inhaling a significant quantity of water.» That would be the equivalent of a human inflating their lungs to become the size of their full abdomen—not exactly possible.

Found along the southwestern coast of Australia, the leafy seadragon, Phycodurus eques, uses its fins not only to propel itself through the water, but as camouflage to resemble a piece of drifting seaweed. Because they have pretty big heads compared to the rest of their body, leafy seadragons are able to concentrate pressure at their mouth to suck in prey. Similar to seahorses and pipefishes, the males carry around fertilized eggs. But without a special pouch, the leafy seadragon carries the eggs beneath its tail.

Scientists call this fish Psychrolutes microporos, but also, more directly, «Fathead.» Smithsonian Magazine even notes that the weird looking creature is largely considered the «World’s Ugliest Animal.» But the blobfish is a pretty incredible sea dweller, surviving at depths in excess of 4,000 feet, where the pressure is 120 times higher than at the surface. And here’s the thing: the blobfish is only actually ugly when it’s brought up to the surface. Most fish have a swim bladder, or a sac of air inside its body to keep buoyant. When fish are removed from their typical environments, these sacs swell up, leading to the innards pushing out through the mouth. Technically, we only think of the blobfish as ugly when it’s dead—so maybe think twice before pointing and laughing.

Known for its vibrant red coloring, the Crossota norvegica is a kind a jellyfish, collected from the deep Arctic Canada Basin. It lives about 2,500 meters beneath the surface, and uses ectodermal cells with nematocysts to sting prey. It’s not exactly clear what these creatures feed on, but it’s most likely a combination of zooplankton and phytoplankton.

This furry-clawed crab looks so unusual that when scientists discovered it 5,000 feet deep on a hydrothermal vent south of Easter Island, they designated it not only a new genus, Kiwa, but a new family, Kiwidae—both named for the mythological Polynesian goddess of shellfish. It’s likely blind and may use bacteria in its furry claws to detoxify its food.

Let’s state the obvious: this thing looks like it’s throwing up. But what you’re actually seeing is the strange mating process of the jawfish, a species native to coral reefs in the Caribbean Sea and western Atlantic. Beyond using their jaws to scoop up sand, the males also use their huge mouths to carry eggs until they hatch. Still, other times, their mouths are like weapons, used in jousting matches—the jawfish truly puts its money where its mouth is.

Smithsonian Ocean

Introduction

Open Ocean Zones

Mesopelagic

Bathypelagic

Abyssopelagic

Hadalpelagic

Seafloor Habitats

Abyssal Plain

Whale Falls

Hydrothermal Vents

Brine Lakes

Cold Seeps

Canyons and Seamounts

Deep Sea Reefs

Finding Food

Bioluminescence

Vertical Migrations

Marine Snow

Tools & Technology

Technologies for Exploring the Deep

At the Smithsonian

Deep Reef Observation Project

Deep Sea Corals

Living in the Deep Sea

Below the ocean’s surface is a mysterious world that accounts for over 95 percent of Earth’s living space—it could hide 20 Washington Monuments stacked on top of each other. But the deep sea remains largely unexplored. As you dive down through this vast living space you notice that light starts fading rapidly. By 650 feet (200 m) all the light is gone to our eyes and the temperature has dropped dramatically. Dive deeper and the weight of the water above continues to accumulate to a massive crushing force. Any light still filtering down has diminished to appear completely black, leaving only animals and bacteria to produce the light found here. By 13,000 feet (4,000 meters), the temperature hovers just below the temperature of your refridgerator. At this depth, we’ve reached the average depth of the deep-sea floor, a place that may start to get a little muddy. The further we dive down from the surface, the less new food is available, making the fight to survive that much more challenging. Despite these harsh conditions, there is life—an astounding variety of creatures that will boggle your mind. You can’t dive to the deep ocean on your own, of course, but scientists have a variety of sophisticated technologies to explore this vast frontier.

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Open Ocean Zones

Oceanographers divide the majority of the ocean midwater into five broad zones. The very deepest depth of the ocean is roughly 2,000 meters deeper than Mount Everest is tall—36,070 feet deep (10,994 m)! Each zone has a different mix of species adapted to its specific light level, pressure, temperature, and community. About three-fourths of the area covered by ocean is deep, permanently dark, and cold. This is the deep sea.

Most are familiar with the surface layer, which extends down 650 feet (200 m) and receives the most sunlight, allowing photosynthetic organisms like phytoplankton to convert sunlight to energy. It is the home of pods of dolphins, schools of fish, and shoals of sharks. Scientists refer to this highly productive area as the epipelagic zone.

But the majority of the space in the ocean is a dark world. Dive below the epipelagic and you will enter the mesopelagic zone. Also known as the twilight zone, this area receives only faint, filtered sunlight, allowing no photosynthetic organisms to survive. Many animals have adapted to the near-darkness with large eyes and counterillumination.

Beginning with the bathypelagic zone, the ocean is completely void of light from the sun, moon and stars. Animals create their own bioluminescent light and, if they haven’t lost them, have highly light-sensitive eyes to see the light produced by other animals. The water temperature is near freezing. Travel deeper and you will find the abyssopelagic zone—the abyss. And finally, the deepest reaches of the ocean are found at the bottom of precipitous trenches. These locations venture into the hadalpelagic zone, places so deep only a handful of humans have ever traveled there so far.

Mesopelagic

The area of the ocean between 650 and 3,300 feet (200-1,000 m) is called the mesopelagic. Barely any light filters down to these depths, and yet still life thrives here. Squid, krill, jellies, and fish are super abundant in this zone. About 90 percent of the world’s fish (by weight) live in the mesopelagic—about 10 billion tons of fish. The bristlemouth fish alone may number at about a quadrillion, making them the most numerous family of vertebrates (animals with a backbone) in the world.

Bathypelagic

The bathypelagic is between 3,300 and 13,100 feet (1,000 and 4,000 m) beneath the ocean surface. It is an area void of light (called aphotic) and at 39 degrees Fahrenheit (4 degrees Celsius), it is very cold. Moreover, the pressure is over 110 times that at sea level. Creatures in this zone must live with minimal food, so many have slow metabolisms. Many rely on marine snow as their main food source. They are also characterized by squishy bodies and slimy skin. The black hagfish, viperfish, anglerfish, and sleeper shark are common fish that call this zone home. While something like the gulper eel, with its massive expandable gullet, is a rare and amazing sight and could almost be mistaken for an alien. Vampire squid and dumbo octopus also venture to these depths.

Abyssopelagic

The Abyssopelagic extends from 13,100 to 19,700 feet (4,000-6,000 m) down to the seafloor or abyssal plain. Animals that can withstand the pressures in this depth, which can reach up to 600 times what is experienced at sea level are highly specialized. Tripod fish are an oddity that can be found in this zone. Often found resting on the seafloor, tripod fish can pump fluid into their elongated fins to make them like rigid stilts (or as their name implies, a tripod), sometimes a few feet high. Rattail fish, octopuses, and sea cucumbers are also well adapted to the intense pressure here.

Hadalpelagic

The hadalpelagic is the very deepest part of the ocean that includes the ocean trenches. It extends from 19,700 feet (6,000 meters) to the very bottom of the Mariana Trench at 36,070 feet (10,994 meters). Very little is known about the creatures that live at such depths. In 2018, scientists officially described a snailfish (Pseudoliparis swirei) at 27,000 feet below sea level, the deepest living fish ever found. The snailfish lacks scales, has large teeth, and does not bioluminesce, a departure from what many people envision in a deep-sea fish. It is the only named fish at such depth. A second has been observed on video, however, it has yet to be captured and formally described. Despite the remoteness of the hadalpelagic, humanity still finds a way to interfere—plastic debris has been found at the bottom of the Mariana Trench.

Seafloor Habitats

Like the open ocean, the seafloor is similarly divided into distinct zones. Right next to the coast is the continental shelf, the submerged part of the continent. This area is characterized by shallow water and mostly exists within the sunlit epipelagic zone. Traveling away from the coast the seafloor will begin to slope down through the mesopelagic and bathypelagic zones into deeper depths. This is the continental slope, the transition between Earth’s continental surface and Earth’s oceanic seafloor. As the slope levels out at the continental rise (roughly 19,700 feet or 6,000 m) it gives way to the abyssal plain, the long stretch that accounts for roughly 70 percent of the world sea floor.

But the ocean floor consists of more than just the flat and seemingly vacant abyssal plain. Pockets of life thrive when food is available, and often these distinct deep sea communities rely on alternate sources of chemical energy that do not originate from the sun—they have figured a way to make do with what they get.

A remarkable white sponge with brown sea feathers, pink brittle stars, and a pink sea feather in the lower right.

Abyssal Plain

The abyssal plain is the relatively level deep seafloor. It is a cold and dark place that lies between 3,000 and 6,000 meters below the sea surface. It is also home to squat lobsters, red prawns, and various species of sea cucumbers. For these creatures food is scarce most of the time. Bits of decaying matter and excretions from thousands of meters above must trickle down to the seafloor, with only a small fraction escaping the hungry jaws of creatures above. Less than five percent of food produced at the surface will make its way to the abyssal plain. Most of this comes in great pulses as the result of phytoplankton blooms. When the phytoplankton are gone, the animals that grew quickly to eat them die and sink to the seafloor.

Whale Falls

For the majority of the ocean floor large animals are scarce. The little nutrition that rains down from above in the form of marine snow is not nearly consistent enough nor substantive enough to fuel a large living creature (though there are billions of tiny ones). Whale or other large animal deaths are different.

Whale falls occur when a whale dies in surface waters and sinks to the bottom of the ocean. Trees, sharks, and large fish can also fall to the seafloor and provide food. The sudden arrival of food prompts creatures from afar to congregate and feast on the fleshy carcass. Once the flesh has been stripped and consumed by predators, bone eaters arrive so that not even the skeleton will remain. In the months and years after a whale fall the site will become the home and food source for millions of creatures.

The skeletal remains of a whale supply a feast for deep sea creatures.

( Ocean Exploration Trust and NOAA ONMS)

For the first month or so that a whale carcass is on the seafloor it is a buffet for scavengers from afar. Many are attracted by the smell of rotting flesh. Within hours of falling, sleeper sharks, rattail fish, and black hagfish flock to the carcass like moths to a flame. Snow crabs, brittle stars, and squat lobsters scurry their way over, and in the ensuing month these scavengers will consume about 40 to 60 kg of flesh per day (88 – 132 pounds). The feeding frenzy also disperses bits and pieces as well as nutrients into the surrounding seafloor where anemones, sea stars, mollusks, worms, and other crustaceans take advantage of the food. Some whale falls can support a blanket of 45,000 worms per square meter—the highest animal density in the entire ocean.

Soon the skeleton is picked clean, but the fall is far from nutrient depleted. Whale bone consists of roughly 60 percent fat by weight, up to 200 times the amount of nutrients typically found at the seafloor. Specially adapted worms and snails take advantage of this feast by boring into the inner bone with acid and absorbing the fats inside with the help of bacteria. The worms, called Osedax worms, ride ocean currents as larvae and then settle on the exposed bone. The first of these larvae develop into females, with one end tunneling into the bone and forming what looks like roots growing through the bone. The other end grows into a feathered fan that lets them extract oxygen from the water. Larvae that arrive later or land on another worm, become males, but never really grow beyond the larval form. Instead they live within the females’ bodies as parasites—sometimes over a hundred live in one female host. Scientists have found about 25 species of bone eating worms since they were first discovered in 2002, and many more are thought to exist. Some are specialized burrowers that dig within the bone for the fat, while others pick apart the surface layers.

These worms house bacteria within their “roots” that take advantage of the sulfur in the bones to make energy in a process called chemosynthesis. Other bacteria types grow directly on the bones and feed on the sulfur. Up to 190 different types of these bacteria have been found on a single whale carcass, and up to 20 percent of those are also found living around hydrothermal vents.

No two whale fall communities are the same. The size of the whale, the depth of the seafloor, and the location all contribute to the types of animals that colonize the area and determine how long it takes for the skeleton to disappear. Our knowledge of whale falls comes from few and far between ROV and AUV encounters, so though whale falls are scarce, scientists estimate they exist at every 5 to 16 km in the Pacific Ocean.

Hydrothermal Vents

Deep beneath the ocean’s surface, towers spew scalding water from within the earth’s crust. These are hydrothermal vents.

Hydrothermal vents exist in volcanically active areas. Seawater makes its way through the cracks in the earth’s crust until it reaches hot magma. As the water heats it absorbs metals like iron, zinc, copper, lead, and cobalt from the surrounding rocks. Hot water rises, carrying these minerals to the surface of the sea floor. There, it meets cool ocean water, an event that sparks chemical reactions and forms solid deposits. Over time the deposits create towers—forming the classic image of a hydrothermal vent. Some spew water filled with black iron sulfide and are aptly named “black smokers,” while others spew white colored elements like barium, calcium, and silicon and are called “white smokers.”

At first inspection, it seems unlikely that anything could live in such an environment—spewing from cracks in the earth’s crust is scalding water that has been heated to temperatures up to 752 degrees Fahrenheit (400 degrees Celsius), a temperature hot enough to melt lead. These vents are also so deep that they never see a glimmer of light from the sun. Despite these obstacles, clams, mussels, shrimp, and gigantic worms thrive in these habitats. Their existence is thanks to bacteria.

Animal life at a hydrothermal vent relies on the energy produced by symbiotic bacteria. The bacteria live either inside the bodies or on the surface of their hosts. But unlike most life on earth that uses light from the sun as a source of energy, these bacteria produce energy through a chemical reaction that uses minerals from the vents.

Scientists first learned of these symbiotic relationships through the study of the Riftia tubeworm. Upon first discovering hydrothermal communities in 1977, scientists were perplexed by the diversity and abundance of life. The worm’s blood red plumes filter the water and absorb both oxygen and hydrogen sulfide from the vents. Hydrogen sulfide is normally poisonous, but the Riftia worm has a special adaptation that isolates it from the rest of the body. Their blood contains hemoglobin that binds tightly to both oxygen and hydrogen sulfide. Further investigation into these unique habitats showed that many of the other creatures that live by the vents also rely on symbiotic bacteria. The yeti crab waves its arms in the water to help cultivate bacteria on tiny arm hairs which it then consumes.

Brine Lakes

It seems like an impossibility—coming across a lake at the bottom of the ocean. But due to chemical and physical properties of water, this is, in fact, a reality.

Brine lakes are super salty pools of water that sit on the ocean floor. The extreme saltiness causes significantly denser water than the average ocean water and, like water and air, the two do not mix. The salt difference is so definitive that sitting above the brine lake, you can visibly see the lake’s surface—even waves when the lake is disturbed.

These brine lakes are a remnant of ancient seas that existed when dinosaurs roamed on land. Many brine lakes have been discovered in the Gulf of Mexico. Millions of years ago, during the Jurassic Period, a shallow sea existed where the Gulf of Mexico now sits. Cut off from the rest of the world’s oceans, the sea slowly evaporated, leaving behind a layer of salt up to 5 miles deep in some locations. By the time the ocean returned to that region, sediment had covered the salt, isolating it from the seawater.

But as the Rocky Mountains began to rise and subsequently erode, the extra weight of the sediment flushed into the Gulf of Mexico via the Mississippi River was enough to break the seal. Salt is naturally lighter than soil and as it became squeezed by the soil above, it began to rise. Near the earth’s surface it began to mix with the seawater that was able to percolate into the sediment. This mixture though, was still many times the salinity of ocean water. The result is a brine lake.

Brine lakes are deadly for ocean creatures. The salt content is so high that creatures that “fall in” often die. Their carcass, pickled and preserved, serves as a warning of the toxic landscape below. But for many creatures the risk is worth it. A brine lake is also an area high in methane and certain bacteria can use the methane in a chemical reaction to produce energy. Animals like mussels and crabs come to feed on the special bacteria by the lake’s edge, and often there are whole communities that live along the shore.

Along with the Gulf of Mexico, brine lakes have been discovered in the Red Sea and off the coast of Antarctica.

Cold Seeps

A cold seep is a place on the ocean floor where fluids and gases trapped deep in the earth percolate up to the seafloor. A cold seep gets its name not because the liquid and gas that emerge are colder than the surrounding seawater, but because they are cooler than the scalding temperature of the similar hydrothermal vent.

Mussels and shrimp at a chemosynthetic cold seep community. Gulf of Mexico.

Cold seeps form at cracks in the earth’s crust. The cracks release buried petroleum-based gas and liquid from deep underground where they formed over millions of years. These liquids and gases are made up of hydrogen and carbon molecules, like methane. It is from these chemicals that cold seep creatures get their energy. Microbes near cold seeps gain energy through chemical reactions, and then pass the energy to symbiotic partners like tubeworms, clams, or mussels. This draws larger predators like octopuses and crabs to the seeps.

Canyons and Seamounts

Like on land, deep canyons can stretch for hundreds of miles across the seafloor. These canyons serve as a habitat where sealife can thrive. The walls, ledges, and bottoms of canyons create a diverse variety of habitats—many of which are steep, and scoured by currents rich in tiny food particles—that enable an array of sea creatures to live there. The rocky ledges are a perfect place for deep sea corals to attach, and the muddy bottom is a soft home for worms and mollusks to burrow. Fish, too, find shelter within the canyon walls, and also a good place to catch a meal.

Canyons are hotspots of life because they are areas of ample nutrition. A canyon acts like a funnel in the ocean, congregating decaying matter that originates from land down to the ocean depths. The geography of a canyon also creates currents of moving water that suspend the amassed nutrition into the water column, often even reaching up into shallower, sunlit depths where photosynthetic algae grow. Krill and crustaceans called amphipods thrive off the phytoplankton, and it is the masses of these zooplankton that attract tuna, swordfish, and sharks to canyons.

A seamount is an underwater mountain that can rise thousands of feet above the seafloor. Just as canyons funnel water, seamounts also influence the flow of water, often diverting deep currents. They are often found at the edges of tectonic plates where magma is able to rise through the surface crust. When dense, nutrient rich ocean currents hit the seamount they deflect up toward the surface, allowing marine life to thrive on the newly supplied food. Crabs, corals, anemones, sea stars, and many other creatures make the walls of seamounts their home. About 80 commercial species live on seamounts, and many are only found near this habitat.

Deep Sea Reefs

It may be the last place you’d expect to find corals—up to 6,000 m (20,000 ft) below the ocean’s surface where the water is icy cold and completely dark. Yet believe it or not, lush coral gardens thrive here. In fact, there are as many known species of deep-sea corals (also known as cold-water corals) as shallow-water species.

Like shallow-water corals, deep-sea corals may exist as individual coral polyps, as diversely-shaped colonies containing many polyps of the same individual, and as reefs with many colonies made up of one or more species. They also serve as a habitat for deep sea creatures like sea stars and sharks. Unlike shallow-water corals, however, deep-sea corals don’t need sunlight. They obtain the energy and nutrients they need to survive by trapping tiny organisms in their polyps from passing currents.

Corals can be found in the deep sea.

Finding Food

Bioluminescence

In a deep, dark world anything that lights up stands out. But in fact, producing light in the deep is the norm rather than the exception. Some creatures produce their own light to snag a meal or find a mate in a process called bioluminescence.

A bright blue ctenophore uses bioluminescence to glow.

Animals can use their light to lure prey towards their mouths, or even to light up the area nearby so that they can see their next meal a bit better. Sometimes the prey being lured can be small plankton, like those attracted to the bioluminescence around the beak of the Stauroteuthis octopus. But the light can also fool larger animals. Whales and squid are attracted to the glowing underside of the cookie-cutter shark, which grabs a bite out of the animals once they are close. The deep-sea anglerfish lures prey straight to its mouth with a dangling bioluminescent barbel, lit by glowing bacteria.

In addition to feeding, creatures of the deep use light in flashy displays meant to attract mates. Or, animals use a strong flash of bioluminescence to scare off an impending predator. The bright signal can startle and distract the predator and cause confusion about the whereabouts of its target. The light can even attract a bigger predator that will eat the attacker. If an animal needs to blend in, bioluminescence can be used to help in camouflage with the use of counterillumination, a display of light that helps them blend into the background.

An unknown deep sea creature glows using bioluminescence.

Vertical Migrations

In the deep-sea food is scarce, but it is also a great place to hide in the dark away from hungry predators. Some creatures have adapted a way of life that takes advantage of both the plentiful surface waters and the safety of the deep. It’s called diel vertical migration.

As the sun sets, fish and zooplankton make massive migrations from the depths up to the ocean’s surface. Despite their small size (some no bigger than a mosquito), these creatures can travel hundreds of meters in just a few hours. Under the light of the moon they feast on the phytoplankton that grew during the day. Then, when the sun comes out and there is enough light for predators to see them again, the zooplankton return to the deep darkness. Often, this repeats every single day. Diel vertical migrations are likely the largest daily migration on the planet.

And while for many creatures partaking in the migration is a way to avoid predators, others take advantage of the reliable movement of potential prey. One tiny plankton, a foraminfera, waits in the path of the migration and ensnares passing copepods, a migrating crustacean, in a web of protruding spines. A layer of these plankton create a dense mine field for the tiny crustaceans to swim through on their path each day. In the arms race of evolution, it pays to be one step ahead.

Diel vertical migrations aren’t the only type of movement between the shallows and deep. Tethered to a life at the surface because they require breathable oxygen, many large animals will make impressive dives to the deep sea in search of their favorite foods. Sperm whales, southern elephant seals, leatherback sea turtles, emperor penguins, and beaked whales are especially good divers. A Cuvier’s beaked whale is known to dive 9,816 feet (2,992 m) deep, and can stay down as long and 3 hours and 42 minutes, making it the deepest diving mammal in the world.

Marine Snow

For much of the deep ocean, food rains down from above in the form of marine snow. The term ‘marine snow’ is used for all sorts of things in the ocean that start at the top or middle layers of water and slowly drift to the seafloor. This mostly includes waste, such as dead and decomposing animals, poop, silt and other organic items washed into the sea from land.

A deep sea squid known as the whiplash squid surrounded in marine snow.

As this material drops deeper and deeper, the particles can grow in size as smaller flakes clump together. The larger size causes them to fall more quickly through the water column—but, even so, the journey to the bottom can take several weeks to years. Scientists have learned more about the travels of marine snow by using sediment traps on the ocean floor. Data from these traps have shown that 815 million tons of carbon reaches the ocean floor every year. These layers of ocean ooze are important carbon sinks—drawing down the decomposing bits of carbon, laying them to rest on the seafloor, and finally burying them.

But not all particles get that far. They are often eaten by fish or marine mammals during their slow fall, just to be digested and pooped out elsewhere in the ocean to begin the cycle all over again. Once the trip is complete, this decomposing hodgepodge can be a welcome food source for animals in deep water and on the sea floor that don’t have reliable food in the sparse darkness. Some animals, such as the vampire squid and its special feeding filaments, have special adaptations to help them better catch and eat the falling particles. The snow is also important to small, growing animals, such as eel larvae, which rely on the snow for months during their development. Marine snow clumps are also swarming with microbes—tiny organisms ranging from algae to bacteria—that form communities around the sinking particles.

Tools & Technology

Technologies for Exploring the Deep

No place on Earth is as distant or as alien as the deep ocean. But we’re now able to explore more and more parts of this remote realm—thanks to a new generation of incredible underwater vehicles.

Some vehicles—known as human occupied vehicles (HOVs)—carry scientists themselves to the deep sea to see firsthand what’s there. Other kinds of unmanned craft let scientists see and study those places they can’t go. For example, scientists can steer remotely operated vehicles (ROVs) from ships at the surface. A cable links the ships to the ROVs, limiting their mobility. Autonomous underwater vehicles (AUVs) have no cable, but they need to be pre-programmed. A new breed of hybrid vehicles (HROVs) combines the best features of ROVs and AUVs: They can have a surface operator, or drop the cable and go it alone.

At the Smithsonian

Deep Reef Observation Project

The Deep Reef Observation Project (DROP) is a Smithsonian research program launched to explore marine life and monitor changes on deep reefs in the southern Caribbean. Scientists turn to submarines to explore at depths too great for SCUBA gear. The Curasub is a 5-person manned submersible capable of descending to 1,000 feet. The state-of-the-art sub is equipped with hydraulic collecting arms that allow for the collection of marine life and the deployment of long-term monitoring devices on the deep reef.

Biological collections from the Curasub off Curaçao have resulted in the discovery of numerous new and rare species of fishes, marine mollusks, echinoderms and crustaceans. This project utilizes the taxonomic expertise of more than a dozen Smithsonian scientists and employs modern molecular tools and digital photography and videography to fully document species and genetic diversity on deep reefs.

Deep Sea Corals

How do you study deep sea coral reefs? With a submarine. Museum curator Andrea Quattrini has spent her career using submarines and remotely operated vehicles to document coral reefs and the species that call these underwater “forests” home. While coral reefs in shallow water are well studied and loved by people, very little is known about their deep sea relatives. We do know that many commercially important species like shrimps, crabs, groupers, rockfish, and snappers rely on deep sea coral reefs for shelter, but this is only based upon a limited number of studies and dives. Scientists, including Quattrini, continue to discover additional species that call deep sea coral reefs home, showing that there is still much to learn about the deep sea.

Living in the Deep Sea

What does it take to live in the deep sea? Curator Karen Osborn wants to know how and why animals adapt in order to survive in a cold, dark, and pressurized environment. Many animals that live in this largest of the earth’s habitats are very bizarre and dramatically different from their closest relatives. For example, some make an extreme effort to see, building huge bulbous eyes that can detect even the smallest glimmer of light, while others completely forfeit any form of sight and instead rely on heightened scent and touch. Since most animal groups have representatives living in the open ocean, learning about the differences in the way these animals live compared to their relatives in shallow water tells us a lot about how this environment changes and shapes the many animals that survive there.