10 Misconceptions About the Ocean

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Hi I'm Elliot, this is mental_floss video, and today I'm gonna talk about some misconceptions about the ocean. You think you know what's going on with the ocean, but you have no idea. 

1. THE SALTINESS IN SEAWATER IS ESSENTIALLY TABLE SALT.

So the water in the ocean is very salty, but it's not composed as if someone just dumped a bunch of table salt into it. Basically, it's considered salt water because it contains a bunch of minerals that come from the Earth's surface. Rain and snow pick up minerals from the ground, which turns into runoff that goes into the ocean. So, seawater has a lot of sodium and chlorine in it, but, it also has a bunch of sulfates, magnesium, calcium, and potassium. And because the definition for salt is so vague, these can all qualify. 

2. THE OCEAN GETS PROGRESSIVELY DEEPER TOWARDS THE MIDDLE.

Much like the land on earth, the surface of the ocean is not consistent. It has its equivalent of mountains and canyons and flat plains. The ocean contains trenches, which is the word scientists use to describe the deepest part. And these are formed when plates meet, which often means that one of the plates moves further down, causing the trench to emerge. One example of this is the Mariana Trench, which is about 1000 miles away from Japan and its deepest point is around 36,000 feet.

3. AN UNDERTOW CAN PULL A PERSON UNDERWATER AND HOLD THEM THERE.

Let me start by saying that people often confuse undertow with rip current. So the undertow is basically a current near the shore that helps keep the water flow consistent as the waves crash. Unlike the undertow, rip currents aren't always present, but they're a stronger current that pulls away from the shore. Neither undertows nor rip currents can pull a person underwater and drown them. Though rip currents are the ones that pull swimmers far away from the shore. Then, people struggle to get back to shore, and that can be dangerous and result in drowning. 

4. THERE ARE NOT HUGE WAVES AWAY FROM SHORE.

People typically only see big waves close to the shore, so they assume that's not a problem in the open ocean, but there are rogue waves which can be a major problem in the middle of the ocean. In order to be considered a rogue wave, the wave must be over twice the "significant wave height," which is basically the mean of the tallest waves in a given area. In 1995, a rogue wave was reported at 84 feet—this can be a major problem for boats, including huge ocean liners. Have fun on your next cruise, guys!

5. ICEBERGS ARE MADE OF SALT WATER.

An iceberg is a chunk of ice that floats in the water after separating from a larger piece of land-based ice. And they're not made up of salt water; they're actually fresh water. That actually makes sense if you think about it because icebergs come from land ice, so they're basically compacted snow, which is fresh water.

6. THE OCEAN APPEARS BLUE BECAUSE IT'S REFLECTING THE SKY.

No. It's not reflecting the color of the blue sky—it's actually absorbing it. Basically the ocean is continually being hit by sunlight, and, as you probably know, that happens in the form of waves, which contain a whole spectrum of color. The ocean typically absorbs the red wavelengths quicker. The blue wavelengths head deeper into the ocean, then, they get scattered and re-emitted from within the ocean, and that's how our eyes take them in. So to us, the ocean appears blue. It's not. It's all different colors.

7. WE COULD EXPLORE THE DEEPEST PARTS OF THE OCEAN.

So you may know that we've only explored less than 5 percent of the ocean, but many people think that's because of a lack of interest. No way guys, it's super interesting down there, OK? The truth is, we just don't have the technology needed in order to explore it. Scientists are trying to develop something known as the "Sea Orbiter," which would basically be a space station for the ocean. It could make more ocean exploration possible, but it's still being developed.

Alright, let's finish up with some misconceptions about marine animals. [Leans over to fish tank] Are you excited? (...they're not real).

8. CORALS ARE MINERAL DEPOSITS. OR FOSSILS. OR ROCKS.

People still find it hard to believe that coral reefs are made up of marine animals. So what happens is corals attach their exoskeletons to objects underwater like rocks, or even shipwrecks. They actually have tentacles so they're able to catch fish and plankton to eat. They might not look like animals, but they are. Please, treat them respectfully.

9. A PORPOISE IS THE SAME AS A DOLPHIN.

Guys, dolphins and porpoises are different animals and they're getting tired of hearing otherwise. There are a few differences. Dolphins have longer beaks and more curved dorsal fins, and porpoises are usually a little larger and make less noise than dolphins do. But, they're both members of the cetacean family and they're both intelligent mammals who live underwater.

10. WHALES SPRAY WATER FROM THEIR BLOWHOLES.

Just like dolphins and porpoises, whales are members of the cetacean family, so they're also mammals who need to breathe air—and they do that through a blow hole on the top of their heads. Once they inhale air through their blowhole, most whales can hold their breath for over an hour, but eventually they need to exhale. When they come above the surface to do that it often looks like they're blowing out water. What they're really blowing out is mostly warm air—it's warm because it's been inside of a huge warm body—and the air outside is usually way cooler than the air that's being exhaled, so it condenses and looks like water. But a whale is primarily inhaling and exhaling air like any mammal does. Oh, and they also exhale mucus. Lots, and just … lots of mucus.

Thanks for watching "Misconceptions" on mental_floss video. If you have a topic for an upcoming "Misconceptions" episode that you would like to see, let us know what it is in the comments below and I'll check it out. I'll see you next week. Bye.

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IKEA
IKEA Is Recalling Its New Dog Water Fountain Due to Suffocation Risk
IKEA
IKEA

In late 2017, IKEA released LURVIG, its first-ever line for pets, a collection that included beds, leashes, food bowls, and other staple products for dogs and cats. Unfortunately, one of those products is now being recalled over safety issues, according to Fast Company. If you own the LURVIG water dispenser, you should take it away from your pet immediately.

The automatic water fountain poses a suffocation hazard, the company announced in a recent statement. The retailer has received two reports of pets dying after getting their head stuck in it.

A water fountain for pets sits next to a bowl full of dog food.
IKEA

The $8 water dispenser debuted in U.S. stores in October 2017 with the rest of its LURVIG line. Awkwardly enough, the product description included assurances of the product’s safety standards. It explained that “the LURVIG range was developed with the assistance of trained veterinarian Dr. Barbara Schäfer, who also works with product risk assessment at IKEA,” and went on to say that “the first thing to consider was safety: ‘Dogs will definitely chew on their toys and bring in dirt from their daily walks. Cats will definitely scratch on most surfaces and are sensitive to smell and texture. So safe, durable materials are very important.’”

It seems that smaller dogs are able to get their faces stuck in the dome-shaped plastic reservoir, which only appears to have one hole in it, at the bottom. As a result, dogs can suffocate if they can’t get out of it.

The product has been removed from IKEA’s website, and the retailer recommends that anyone who bought it stop using it and return it to the nearest IKEA store for a refund.

[h/t Fast Company]

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Alamy
10 Facts About the Portuguese Man O' War
Alamy
Alamy

Something a lot scarier than any Jersey Devil has been washing up on beaches in the Garden State lately: This month, the dangerous Portuguese Man O’ War—which has a potentially deadly sting—has been sighted in Cape May and Wildwood, New Jersey, which could lead to problems for beachgoers. Read on to learn more about these unusual creatures.

1. IT'S NOT A JELLYFISH.

The Portuguese Man o’ War may look like a bloated jellyfish, but it’s actually a siphonophore—a bizarre group of animals that consist of colonies made up of dozens, hundreds, or even thousands of genetically-identical individual creatures. A siphonophore starts out as a fertilized egg. But as it develops, it starts "budding" into distinct structures and organisms. These tiny organisms—called polyps or zooids—can’t survive on their own, so they merge together into a tentacled mass. They must cooperate as one in order to do things like travel and catch food.

Though the zooids within a Man O’ War are basically clones, they come in different shapes and serve different purposes [PDF]. Dactylozooids are long hunting tentacles built to ensnare prey; gastrozooids are smaller tentacles which digest the food; and gonozooids are dangling entities whose job is to facilitate reproduction. Every Man O’ War also has a pneumatophore, or “float”—an overgrown, bag-like polyp which acts as a giant gas bladder and sits at the top of the colony. Capable of expanding or contracting at will, it provides the Man O’ War with some buoyancy control. An expanded float also enables the colony to harness winds to move around.

2. A CLOSE RELATIVE IS THE INDO-PACIFIC “BLUEBOTTLE.”

A view of a bluebottle under water.
iStock

When we say “Portuguese Man O’ War,” we’re talking about Physalia physalis, the bizarre siphonophore that’s scaring New Jerseyans right now. Also known as the Atlantic Portuguese Man O’ War, it can be found in warmer parts of the Pacific, the Caribbean, the Indian Ocean, and of course, the Atlantic.

Another kind of siphonophore which regularly stings beachgoers is the so-called bluebottle, Physalia utriculus. It’s sometimes called the Indo-Pacific “Portuguese” Man O’ War and is restricted to the Pacific and Indian Oceans. It’s smaller than the Atlantic species and unlike its bigger counterpart—which has multiple hunting tentacles—it hunts with a single, elongated tentacle.

3. THE NAME “PORTUGUESE MAN O’ WAR” IS PROBABLY A NAVAL REFERENCE.

In the age of sailing, many European navies used tall warships loaded with cannons and propelled by three masts. British sailors took to calling this kind of vessel a “Man of War.”

What does that have to do with Physalia physalias? These colonies spend a lot of time floating at the water’s surface, and when the gas bladder is expanded, it looks—and acts—a bit like a sailboat, hence the “Man O’ War.” As for the Portuguese part, 19th century scientists proposed that sailors encountered it near the Portuguese island of Madeira, while modern etymologists tend to think that it looked like the Portuguese version of the ship.

Or at least that’s one explanation for the creature’s peculiar name. It’s also been suggested that Renaissance-era sailors thought the pneumatophores resembled the helmets worn by Portugal’s soldiers during the 16th century.

4. MAN O’ WAR TENTACLES CAN BE UP TO 165 FEET LONG.

Two Portuguese Man o' War washed up on the beach with their tentacles stretched out.
iStock

At least, that’s the maximum length for the dactylozooids—which are normally around 30 feet long and use venom-spewing cells to deliver painful, neurotoxic stings. When a tentacle is detached from the rest of the colony, it might wash ashore somewhere or drift around for days on end until it decomposes. Be warned: Even a severed tentacle can sting you.

5. ON RARE OCCASIONS, STINGS CAN BE FATAL TO HUMANS.

The odds of being killed by a Portuguese Man O’ War are slim. But just because deaths are rare doesn't mean you should touch one: On February 11, 2018, 204 people in Hollywood, Florida were treated for stings, which can lead to red welts on the skin, muscle cramps, elevated heart rates, and vomiting.

Still, the creatures can kill: One unlucky victim suffered a full cardiovascular collapse and died after getting too close to a Man O’ War in eastern Florida back in 1987. More recently, a woman swimming off Sardinia was stung by one and died of what was believed to be anaphylactic shock.

6. SOME FISH LIVE IN THEM.

Given that tiny fish make up about 70 to 90 percent of the Man O’ War’s diet (it also eats shrimp and other crustaceans), Nomeus gronovii, a.k.a. the Portuguese Man O’ War Fish, is playing a dangerous game: It lives among the siphonophore's tentacles even though it's not immune to its stings, swimming nimbly between the stingers. Young fish eat planktons which wander under their hosts and, as they get older, will sometimes steal the Man O’ War’s prey—or nibble on its tentacles.

7. SEA SLUGS LIKE TO STEAL THEIR TOXINS.

The Man O’ War has a long list of enemies. Loggerhead sea turtles and the bizarre-looking ocean sunfish are thick-skinned enough to eat them. There are also “blue dragon” sea slugs, which not only devour the Man O’ War but actively harvest and appropriate its toxins. After storing Man O’ War stinging cells in their own skins, the blue dragons can use it as a predator deterrent.

8. MAN O’ WAR COME IN PRETTY COLORS.

A pink-tinted Portuguese Man O' War with blue tentacles in the surf at a beach.
iStock

Although it’s translucent, the float is usually tinted with blue, pink, and/or purple hues. Beaches along the American Gulf Coast raise purple flags in order to let visitors know when groups of Man O’ War (or other potentially deadly sea creatures) are at large.

9. EVERY COLONY HAS A SPECIFIC SEX.

The Man O' War's gonozooids have sacs that house ovaries or testes—so each colony can therefore be considered “male” or “female.” Though marine biologists aren’t completely sure how the Man O’ War procreates, one theory is that the gonozooids release eggs and sperm into the open ocean, which become fertilized when they cross paths with floating eggs or sperm from other Man O’ War colonies. This “broadcast spawning” method of reproduction is also used by many species of coral, fan worms, sea anemone, and jellyfish.

10. LOOK OUT FOR MAN O’ WAR LEGIONS.

The Man O’ War isn't always seen in isolation. Legions consisting of over 1000 colonies have been observed floating around together. Because they drift along on (somewhat) predictable winds and ocean currents, it’s possible to anticipate where and when a lot of the creatures will show up. For example, the Gulf Coast’s Man O’ War season arrives in the winter months.

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