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Diana Robinson via Flickr // CC BY-ND 2.0
Diana Robinson via Flickr // CC BY-ND 2.0

15 Electrifying Facts About Jellyfish

Diana Robinson via Flickr // CC BY-ND 2.0
Diana Robinson via Flickr // CC BY-ND 2.0

Colorful, dangerous, and mesmerizing, there's a lot more going on with these gelatinous creatures than meets the eye. Here are 15 electrifying facts about these undersea beauties.

1. JELLYFISH CAN STING WHEN THEY'RE DEAD.

Even when they’re attached to a carcass, the cells of a jellyfish’s venomous tentacles will sometimes continue to fire: In 2010, about 150 New Hampshire beach-goers were stung by the disembodied tentacles of a dead lion’s mane jelly.

2. JELLYFISH ARE 95 PERCENT WATER.

From the outside, jellyfish look like squishy, insubstantial blobs, and this is reflected in their structural makeup.  Jellyfish are 95 percent water with the rest of them accounting for minerals and proteins. Between their two dermis layers is a gelatinous, water-based substance called mesoglea that contains muscle cells, nerve cells, and structural proteins.

3.  JELLYFISH ARE GOOD AT SHUTTING DOWN NUCLEAR POWER PLANTS. 

Nuclear power plants in Scotland, Sweden, California, Israel, and Japan have all been taken offline by slimy swarms of jellyfish. Power plants use outside water sources to cool down the fuel rods inside their reactor core. If this water contains jellies, they can clog up the system and force plants to shut down.

4. ONE SPECIES CAN AGE BACKWARD.

At any stage in its development, Turritopsis dohrnii—also known as the “immortal jellyfish” or the “Benjamin Button jellyfish”—is capable of reversing its life cycle until it reverts to a polyp, from which it starts the whole process over again. Some scientists believe by aging backward to escape death this jellyfish has unlocked the key to immortality.

5. JELLYFISH ARE OLDER THAN DINOSAURS.

Jellyfish have inhabited the earth’s oceans for over 650 million years, making them more ancient than sharks and dinosaurs.

 6. THERE’S A JELLYFISH SPECIES NAMED AFTER FRANK ZAPPA.

The Phialella zappai was named in honor of Frank Zappa, the favorite musician of the scientist who discovered it. Zappa was quoted as saying, “There is nothing I'd like better than having a jellyfish named after me."

7. JELLYFISH HAVE BEEN TO SPACE.

In 1991, NASA made history by sending 2478 jellyfish polyps to space. It was part of an experiment called “The Effects of Microgravity-Induced Weightlessness on Aurelia Ephyra Differentiation and Statolith Synthesis.” The creatures were kept in flasks and bags that contained artificial seawater, which astronauts then injected with chemicals that encouraged them to reproduce. By the end of the experiment there were approximately 60,000 jellyfish in the Earth’s orbit.

8. JELLYFISH DON’T HAVE ORGANS.

Jellies don’t have lungs, intestines, or stomachs, but they do use a much simpler system that’s able to get the job done. Their bodies are composed of two cell layers—the external epidermis and the internal gastrodermis. The gastrodermis has one opening it uses to consume food, expel waste, and exchange reproductive materials. They are able to absorb oxygen and nutrients through the cell walls of their inner layer and even through their outer layer.

9.  THEY COME IN MANY SIZES.

The largest jelly is the lion’s mane jellyfish, which grows up to 6 meters in diameter and has stinging tentacles up to 50 meters long. The smallest species is the Common Kingslayer. It’s smaller than a fingernail and it’s also one of the most venomous creatures on earth.

10. JELLYFISH HAVE IMPORTANT MEDICAL APPLICATIONS.

A few years ago, scientists from the Mayo Clinic injected unfertilized cat eggs with a green fluorescent protein found in crystal jellies and a gene from rhesus monkeys known to block the virus that causes feline AIDS. The only significance of the jellyfish protein was that it would indicate if the gene had successfully transferred. Sure enough, when the kittens were born, they glowed bright green when placed under a black light.

11. A GROUP OF JELLYFISH WAS ONCE CALLED A SMACK.

Sadly, that’s not often used anymore. The preference these days is to call a large gathering of jellies a "swarm."

12. JELLYFISH REPRODUCE SEXUALLY AND ASEXUALLY.

Jellyfish can reproduce sexually by releasing sperm and eggs into the ocean where they form tiny, free-swimming larvae. These larvae then grow into polyps which attach to smooth surfaces and can split into numerous young jellyfish, thus reproducing asexually.

13. RESEARCHERS HAVE BUILT A HUMAN-SIZED JELLYFISH ROBOT.

Researchers at Virginia Tech hoping to build self-powered aquatic robots used jellyfish as a model, building a 170 pound aquatic bot they dubbed Cyro to test their idea. The propulsion system of a jellyfish runs on very little energy, which makes it a great model for autonomous, undersea robots of the future.

14.  JELLYFISH ARE EDIBLE.

Sea turtles aren’t the only creatures that like to feast on jellies now and then. Blubber jellies, for example, are considered a delicacy in parts of Asia, and students at a Japanese high school once used powdered jellyfish to make salted caramels.

15. THEIR NERVOUS SYSTEM IS THE MOST BASIC OF ANY MULTICELLULAR ANIMAL.

Instead of a brain, jellies use a “nerve net” to process sensory information. Specialized structures like statocysts help jellyfish know if they're facing up or down, and rhopalia allow them to sense light, chemicals and movement in the water. This is the most basic nervous system a multicellular organism can have, and it’s also found in hydras and anemones.

All photos via Getty Images unless otherwise noted.

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Smart Shopping
25 Dapper Outfit Choices for Fashionable Pets
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Lavishing your furry friends with adorable attire is a benefit of pet ownership that they don't mention on the adoption forms. Whether you prefer practical clothing like sweaters and jackets or statement pieces like bow ties and tutus, these dapper duds are perfect for a howl-iday or "gotcha day" gift, or simply for saying, "Who's the cutest little pupper in pajamas? You are!"

1. CASHMERE DOG SWEATER; FROM $165

dog in sweater
Canine Styles

This classic cable-knit cashmere sweater is a sophisticated look for Fido or Finn. Get it from Canine Styles, a luxury dog emporium in New York City that has plenty of posh and preppy outfits.

Find It: Canine Styles

2. TOGGLE DOG COAT; $85

dog in coat
Canine Styles

This toggle coat (available in orange, navy, and tan) is as fashionable as it is warm. Made of Melton wool, it has Velcro closures to make getting dressed easy. It's great for long walks in the country.

Find It: Canine Styles

3. DOG TUXEDO; FROM $90

Dog in tuxedo
Etsy

This satin tuxedo is perfect for the canine members of your wedding party, though it will brighten up any other occasion as well. The custom, handmade outfit comes complete with a snappy bow tie.

Find It: Etsy

4. DOG BELLE DRESS; FROM $45

Dog Belle Dress
Etsy

The queen of your castle can feel like a Disney princess in her very own version of Belle's iconic yellow dress from Beauty and the Beast. This ball gown is made from yellow crepe satin with chiffon overlay on the bodice and features hand-painted gold detailing on the skirt. Enchanted rose not included.

Find It: Etsy

5. POODLE SKIRT OUTFIT FOR DOGS; $26

Rubies Pink Fifties Girl Pet Costume
Amazon

What if you could buy a 1950s poodle skirt for your poodle? This retro dress is comprised of a pink poodle skirt, striped bodice, and sequined belt, and comes with a bow headband.

Find It: Amazon

6. RIBBED CROCHET BUNNY SWEATER; $25

bunny in a sweater
Etsy

Your snuggle-bunny will look like a little fancy-pants in this ribbed crochet sweater. Choose from seven colors, including this dashing deep red.

Find It: Etsy

7. BESPOKE MONOGRAM DOG SWEATER; FROM $155

Dog in sweater
Ruby Rufus

Bespoke clothing isn't just for humans: British luxury dog clothing brand Ruby Rufus will make your pooch a custom monogram sweater made with 100 percent Italian cashmere. You can even order it in your dog's favorite color.

Find It: Ruby Rufus

8. HOT PINK DOG TUTU; $17

Dog in hot pink tutu
Etsy

Tutus look absolutely adorable on tiny humans and animals alike. If your pooch wants to get in touch with its inner ballerina, then grab this hot pink number from Etsy. Rave reviews are a sure thing.

Find It: Etsy

9. PINK DOG POLO SHIRT; $35

Dog Pink Polo Shirt
Canine Styles

This pink polo shirt is perfect for your preppy fur baby. It features not one but a veritable multitude of crocodiles. They'll be the most dapper dog at the country club.

Find It: Canine Styles

10. DOG BARN COAT WITH BROWN CORDUROY COLLAR; $85

Dog in barn coat
Canine Styles

When it's time for a walk, your dog will look effortlessly chic in this fancy barn coat. It comes in navy, cranberry, orange, hot pink, and loden and features convenient pockets for anyone with opposable thumbs.

Find It: Canine Styles

11. WHITE PET NECK RUFF; $26

Pet Neck Ruff
Etsy

Your canine or kitty will look like their painting belongs in London's National Portrait Gallery with this Elizabethan neck ruff.

Find It: Etsy

12. CHICKEN SWEATER; $25

chicken wearing sweater
Etsy

Chickens can get cold when they're strutting around outside. A sweater (well, more like sweater vest) for your bird can also help prevent feather picking during molting season. Or, it can simply keep them warm while they stare pensively across a snowy landscape.

Find It: Etsy

13. PET CIRCLE SCARF; $15

dog in scarf
Etsy

An infinity scarf is a perfect burst of color on a dreary early morning walk. The proprietor of Mitten Made on Etsy originally designed this wool snood for her miniature Dachshund to help keep her warm during the long, cold winters in Michigan.

Find It: Etsy

14. FAB DOG TRAVEL RAINCOAT; FROM $18

Fab Dog Travel Raincoat
Chewy

This timeless yellow rain slicker will look great on any puppy when it's raining cats and dogs. It's made of 100 percent waterproof nylon shell that keeps fur dry. Bonus: It's perfect for an It Halloween costume.

Find It: Chewy

15. LACE CAT OR DOG COLLAR; FROM $10

cat in lace collar
Etsy

This handmade, white lace collar is a must-have for fancy felines. It's also embellished with a large rhinestone.

Find It: Etsy

16. FITWARM PENGUIN PAJAMAS FOR DOGS; FROM $10

Fitwarm Cute Penguin Xmas Dog Pajamas
Amazon

Keep your pupper warm on cold winter nights with these penguin PJs. They're great for doggie sleepovers or lazy weekends on the couch watching Netflix.

Find It: Amazon

17. PLAID CASHMERE DOG COAT; FROM $225

dog in plaid coat
Canine Styles

Your dog will look like a proper gentleman in this smart plaid peacoat. This fine garment is made of cashmere with a faux fur lining and leather buttons, and is a perfect shield against chill and fog.

Find It: Canine Styles

18. SATIN PET BOW TIE; FROM $8

Satin Bow Tie for Dog
Etsy

This satin doggie bow tie is perfect for any occasion. It comes in several colors and features a Velcro fastener that makes it easy to attach to a collar. Plus, 10 percent of every sale goes to charity: specifically to SPCA (Society for the Prevention of Cruelty to Animals) and Feeding Pets of the Homeless.

Find It: Etsy

19. RED DOG DRESS; FROM $34

dog in dress
Etsy

Your good boy or girl will look red carpet-ready in this elegant gown. The voluminous tulle skirt is to die for, and each bow is embellished with beads. Custom orders are also available.

Find It: Etsy

20. DOG TIE; FROM $13

Dog tie
Etsy

Your pooch will be ready to stun at any black tie event. This tie is designed like a collar, making it easy to dress your four-legged friend. This Etsy store gives back: 10 perfect of all sales are donated to an animal protection association.

Find It: Etsy

21. NAUTICAL DOG DRESS WITH MATCHING LEASH; $20

Dog sailor dress
BaxterBoo

Perfect for a day on the town or setting sail in a schooner, this is the sailor outfit you never knew your best furry friend needed. This vintage throwback also comes with a matching leash.

Find It: BaxterBoo

22. TARTAN FLANNEL PET BOW TIE; $5.50

tartan pet bow tie
Etsy

Your dog or cat will turn heads in this flannel tartan bow tie. It has a convenient elastic loop that slides over your pup's collar.

Find It: Etsy

23. PUCCI DOG SHIRT; $23

dog in Pucci dog shirt
Etsy

Only the fanciest dogs wear, err, Pucci. Grab this punny "designer" t-shirt for your pup. This high-quality cotton statement piece is perfect for small breeds.

Find It: Etsy

24. PINK POLKA DOT AND LACE DOG HARNESS DRESS; $20

Pink Polka Dot and Lace Designer Dog Harness Dress
BaxterBoo

This feminine pink polka dot dress is simply adorable. It features a convenient built-in harness and comes with a matching leash.

Find It: BaxterBoo

25. PET SWEATER VEST; $6

pet sweater vest
Amazon

Your dog or cat will look like an erudite Oxford professor in this sweater vest. Note that the button on the pocket is shaped like a bone.

Find It: Amazon

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Animals
Switzerland Just Made It Illegal to Boil Live Lobsters
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No, lobsters don’t scream when you toss them into a pot of boiling water, but as far as the Swiss government is concerned, they can still feel pain. The path most lobsters take to the dinner plate is supposedly so inhumane that Switzerland has banned boiling lobsters alive unless they are stunned first, The Guardian reports.

The new law is based on assertions from animal rights advocates and some scientists that crustaceans like lobsters have complex nervous systems, making death by boiling incredibly painful. If chefs want to include lobster on their menus, they’re now required to knock them out before preparing them. Acceptable stunning methods under Swiss law include electric shock and the “mechanical destruction” of the lobster’s brain (i.e. stabbing it in the head).

The government has also outlawed the transportation of live lobsters on ice or in icy water. The animals should instead be kept in containers that are as close to their natural environment as possible until they’re ready for the pot.

Proponents of animal rights are happy with the decision, but others, including some scientists, are skeptical. The data still isn’t clear as to whether or not lobsters feel pain, at least in the way people think of it. Bob Bayer, head of the University of Maine’s Lobster Institute, told Mental Floss in 2014 that lobsters “sense their environment, but don’t have the intellectual hardware to process pain.”

If you live in a place where boiling lobsters is legal, but still have ethical concerns over eating them, try tossing your lobster in the freezer before giving it a hot water bath. Chilling it puts it to sleep and is less messy than butchering it while it’s still alive.

[h/t The Guardian]

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