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10 Facts About the Portuguese Man O' War

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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.
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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.
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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.
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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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Potato-Based Pet Food Could Be Linked to Heart Disease in Dogs
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If you have a pup at home, you may want to check the ingredients listed on that bag of dog food in your cupboard. The U.S. Food & Drug Administration has warned that potato-based pet foods might be linked to heart disease in dogs, Time reports.

Foods containing lentils, peas, and other legume seeds are also a potential risk, the agency’s Center for Veterinary Medicine announced.

“We are concerned about reports of canine heart disease, known as dilated cardiomyopathy (DCM), in dogs that ate certain pet foods containing peas, lentils, other legumes or potatoes as their main ingredients,” Martine Hartogensis of the veterinary center said in a statement. “These reports are highly unusual as they are occurring in breeds not typically genetically prone to the disease.”

Recent cases of heart disease have been reported in various breeds—including golden and Labrador retrievers, miniature schnauzers, a whippet, a shih tzu, and a bulldog—and it was determined that all of the dogs had eaten food containing potatoes, peas, or lentils.

While heart disease is common in large dogs like Great Danes and Saint Bernards, it’s less common in small and medium-sized breeds (with the exception of cocker spaniels). If caught early enough, a dog’s heart function may improve with veterinary treatment and dietary changes, the FDA notes. While the department is still investigating the potential link, it’s best to err on the side of caution and avoid foods containing these ingredients until further notice.

As shown by the recent romaine lettuce scare linked to E. coli, the FDA is unable to request a food recall unless a specific manufacturer or supplier can be identified as the source of contamination. Instead, public notices are generally issued to warn consumers about a certain food while the agency continues its probe.

[h/t Time]

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10 Science-Backed Tips for Getting a Cat to Like You
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Like so many other humans, you might find cats to be mysterious creatures. But believe it or not, it’s not that hard to make friends with a feline, if you know what to do. Here are some tips on how to effectively buddy up with a kitty, drawn from scientific studies and my own experience as a researcher and cat behavioral consultant.

1. LET THE CAT CALL THE SHOTS.

When we see cats, we really want to pet them—but according to two Swiss studies, the best approach is to let kitty make the first move.

Research done in 51 Swiss homes with cats has shown that when humans sit back and wait—and focus on something else, like a good book—a cat is more likely to approach, and less likely to withdraw when people respond. (This preference explains why so many kitties are attracted to people with allergies—because allergic people are usually trying to not pet them.) Another study found that interactions last longer and are more positive when the kitty both initiates the activity and decides when it ends. Play a little hard to get, and you might find that they can’t get enough of you.

2. APPROACH A CAT THE WAY THEY GREET EACH OTHER (SORT OF).

person extending finger to cat's nose
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Felines who are friendly with each other greet each other nose to nose. You can mimic that behavior by offering a non-threatening finger tip at their nose level, a few inches away. Don’t hover, just bend down and gently extend your hand. Many cats will walk up and sniff your finger, and may even rub into it. Now that's a successful greeting.

3. PET CATS WHERE THEY LIKE IT MOST …

They're very sensitive to touch, and generally, they tend to like being petted in some places more than others. A small 2002 study demonstrated that cats showed more positive responses—like purring, blinking, and kneading their paws—to petting on the forehead area and the cheeks. They were more likely to react negatively—by hissing, swatting, or swishing their tails—when petted in the tail area. A more recent study validated these findings with a larger sample size—and many owners can testify to these preferences.

Of course, every animal is an individual, but these studies give us a good starting point, especially if you're meeting a cat for the first time.

4. … AND IF YOU GET NEGATIVE FEEDBACK, GIVE THE CAT SOME SPACE.

There are plenty of signs that a cat doesn't like your actions. These can range from the overt—such as hissing and biting—to the more subtle: flattening their ears, looking at your hand, or twitching their tails. When you get one of those signals, it’s time to back off.

Many of the owners I work with to correct behavioral issues don't retreat when they should, partially because they enjoy the experience of petting their cat so much that they fail to recognize that kitty isn’t enjoying it too. You can’t force a feline to like being handled (this is especially true of feral cats), but when they learn that you’ll respect their terms, the more likely they will be to trust you—and come back for more attention when they're ready.

5. DON’T OVERFEED YOUR CAT.

Many think that food equals love, and that withholding food might make your kitty hate you, but a recent study of obese felines from Cornell University showed the opposite is true—at least for a period of time. About a month after 58 overweight kitties were placed on a diet, three-quarters of their owners reported that their dieting felines were more affectionate, purred more often, and were more likely to sit in their owner's lap. This adorable behavior came with some not-so-cute side effects—the cats also begged and meowed more—but by week eight, both the good and bad behavior had abated for about half the animals.

Regardless of whether a diet makes your pet cuddlier, keeping your pet on the slender side is a great way to help them stay healthy and ward off problems like diabetes, joint pain, and uncleanliness. (Overweight animals have difficulty grooming themselves—and do you really want them sitting on your lap if they can’t keep their butt clean?)

6. PLAY WITH THEM—A LOT.

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Most of the behavior problems that I've witnessed stem from boredom and a lack of routine playtime. No one thinks twice about walking their dog every day, but many people fail to recognize that felines are stealth predators who need a regular outlet for that energy. A recent study suggested that cats prefer human interaction over food, but a closer look at the data demonstrated that what really attracted them to humans was the presence of an interactive toy. One of their top choices is a wand-style toy with feathers, strings, or other prey-like attachments that evoke predatory behavior. Daily interactive play is a great way to bond with them when they’re not in the mood to cuddle—and to keep them fit. Try the Go-Cat Da Bird or any of Neko Flies interchangeable cat toys.  

7. KEEP YOUR CAT INDOORS.

A study conducted in Italy showed that felines who stayed mostly indoors (they had one hour of supervised access to a small garden each day) were more “in sync” with their owners than felines who were allowed free access to the outdoors. The indoor kitties were more active during the day, when their owners were likely to be active, and less active at night, when humans like to sleep. (Many people believe cats are nocturnal, but they are naturally crepuscular—active at dawn and dusk.)

8. SOCIALIZE CATS WHEN THEY'RE YOUNG.

Multiple studies have shown that just a few minutes a day of positive handling by humans helps kittens grow up to be friendlier and more trusting of humans. The ideal age to socialize kittens is when they're between 2 and 9 weeks old. One 2008 study found that shelter kittens that had been given a lot of "enhanced socialization"—additional attention, affection, and play—were, a year later, more affectionate with their owners and less fearful than other kittens adopted from the same shelters.

You can help socialize kittens by volunteering as a foster caretaker. Fostering ensures they get plenty of interaction with people, which will help them will be comfortable around potential adopters. You'll also be doing your local shelter a huge favor by alleviating overcrowding.

9. TAKE THE CAT'S PERSONALITY—AND YOUR OWN—INTO CONSIDERATION WHEN ADOPTING.

If you want to adopt an older animal, take some time at the shelter to get to know them first, since adopters of adult cats report that personality played a big role in their decision to take an animal home permanently and had an impact on their satisfaction with their new companion. Better yet, foster one first. Shelters can be stressful, so you'll get a better sense of what an animal is really like when they're in your home. Not all cats are socialized well when they're young, so a cat may have their own unique rules about what kinds of interactions they're okay with.

It's also key to remember that a cat's appearance isn't indicative of their personality—and it's not just black cats who get a bad rap. In 2012, I published a study with 189 participants that showed that people were likely to assign personality traits to felines based solely on their fur color. Among other things, they tended to think orange cats would be the nicest and white cats the most aloof. (Needless to say, these are inaccurate assumptions.) And it's not just the kitty's personality that matters—yours is important too. Another study I conducted in 2014 of nearly 1100 pet owners suggested that self-identified “cat people” tend to be more introverted and anxious when compared to dog people. (We’re also more prone to being open-minded and creative, so it’s not all bad.) If you’re outgoing and active, a more playful feline could be for you. If you prefer nights spent snuggling on the couch, a mellow, shy-but-sweet lovebug could be your perfect pet.

10. BE A KEEN OBSERVER OF THEIR BEHAVIOR.

Overall, use your common sense. Be a diligent and objective observer of how they respond to your actions. Feline body language can be subtle—something as small as an eye-blink can indicate contentment, while ear twitches might signal irritation—but as you learn their cues, you'll find yourself much more in tune with how they're feeling. And if you adjust your behaviors accordingly, you'll find soon enough that you've earned a cat's trust.

Mikel Delgado received her Ph.D. at UC-Berkeley in psychology studying animal behavior and human-pet relationships. She's a researcher at the UC Davis School of Veterinary Medicine and co-founder of the cat behavior consulting company Feline Minds.

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