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NOAA Photo Library, Flickr // CC BY 2.0
NOAA Photo Library, Flickr // CC BY 2.0

7 Impressive Animal Defense Mechanisms

NOAA Photo Library, Flickr // CC BY 2.0
NOAA Photo Library, Flickr // CC BY 2.0

The deep-sea squid known as Octopoteuthis deletron has a startling defense mechanism: When threatened, the squid attacks its predator and then pulls away, breaking off the tip of its own arm and leaving it behind as a diversion. As the arm continues to glow and twitch, the squid makes its escape.

But this squid isn't the only creature with a bizarre tactic for keeping itself alive. Here are several other animals with impressive defense mechanisms.

1. THE LIZARD THAT SHOOTS BLOOD FROM ITS EYES

The Texas Horned Lizard is a scary-looking creature. Brown, plump and perfectly camouflaged in its native sandy environment, its first line of defense is its spiky demeanor. If the sharp spikes and horns don't ward off predators, the lizard steps it up a notch and squirts a well-aimed stream of blood out of its eyes. The stream of blood, which can go as far as 5 feet, is mixed with a foul-tasting chemical that wards off predators. But this odd weapon comes at a cost: The lizard may release one-third of its total blood supply this way, amounting to 2 percent of its body mass. Unfortunately, its population numbers are dropping thanks to a threat that won't retreat after a well-aimed squirt: habitat loss due to rapid urbanization in the Lone Star State. 

2. THE HAIRY FROG THAT BREAKS ITS OWN BONES

Trichobatrachus robustus, aka hairy or horror frog

Emőke Dénes, Wikimedia Commons // CC BY-SA 4.0

What if every time you felt threatened, your first and only method of defense was to break your own bones and use them for weapons? Meet the hairy frog, a Central African species. When breeding, the male frogs develop thin strands of skin along the sides of their bodies that resemble hair. In theory, these strands also allow the frogs to take in more oxygen while they watch over their eggs. But what's really compelling about this frog is its ability to crack its own toe bones and push them through their skin to form sharp claws, which are great for warding off would-be attackers.

While it's not completely clear what happens to the bones after the threat of attack subsides, researchers believe the bones slide back under the skin when the frog's muscles relax.

3. THE NEWT THAT TURNS ITS RIBS INTO SPIKES

spanish ribbed newt

The hairy frog isn't the only amphibian that uses its bones for weapons. When attacked, the Spanish ribbed newt shifts its ribs forward at an angle and pushes them through its stretched skin. The resulting effect is a row of spikes on either side of its body. Like the hairy frog, the newt has to force the bones through its skin every time it is attacked, but the mechanism seems to cause little or no harm to the creature. Maybe one day it'll get its own robot protector: A team of researchers at the the Swiss university EPFL created a robotic salamander inspired by the newt, which they called the Pleurobot (after its scientific name, Pleurodeles waltl).

4. THE TERMITE THAT BLOWS ITSELF UP

Talk about taking one for the team. When under attack, a species of termites found in the French Guiana rain forests sends older worker bugs on suicide missions to defend the whole colony. These older bugs, no longer as useful to the pack as they once were, come equipped with "explosive backpacks" that, over a lifetime, fill with toxic crystals produced by glands in the abdomen. When mixed with salivary gland secretions, these crystals create a toxic liquid that explodes on enemies, paralyzing them and killing the worker at the same time. These termites aren't alone among insects in using a suicidal defensive tactic: When faced with a threat, an ant found in Borneo expands its abdomen until it ruptures, shooting out a toxic liquid

5. THE FISH THAT SLIMES ITS ENEMIES

Hagfish are eel-shaped marine animals with the incredibly useful ability to slime their enemies. When threatened, the hagfish emit a slime from their pores that, when mixed with water, expands into a gelatinous goo that can either trap predators or suffocate them by clogging their gills. The video above shows a hagfish being attacked 14 separate times by sharks and other big fish, and coming out completely unharmed. Each predator took one bite before immediately spitting the hagfish out and swimming away, gagging. The best time to encounter a hagfish is probably after it's emptied its slime glands withstanding such an onslaught; the glands take three to four weeks to refill.

6. THE SEA CUCUMBER THAT SHOOTS ORGANS OUT OF ITS ANUS

sea cucumber on coral reef
iStock

Sea cucumbers can seem pretty boring. There are some 1250 known species of these sedentary creatures in the world, and many of them do indeed look like cucumbers. But when it comes to survival, things get interesting. Like starfish and sea urchins, sea cucumbers are echinoderms, and they can regenerate lost body parts if necessary. This comes in handy when they're threatened. The sea cucumber will expel its internal organs, which are sticky and sometimes contain a toxic chemical that can kill predators. They don't have much of a defense against pollution though, which is a problem, because they're superstar ocean-floor cleaners.

7. THE OPOSSUM THAT PLAYS DEAD

possum playing dead in the grass
Tony Alter, Flickr // CC BY 2.0

You can't do a roundup like this without at least mentioning the opossum. We typically refer to this creature's infamous defense mechanism as "playing dead," but there's actually nothing playful about it; the act is completely involuntary. Under intense fear, opossums fall into a comatose-like state that can last for hours, long enough to convince any predator that the opossum is already dead. Also unappetizing: Fear causes these animals to emit a corpse-like smell that only adds to their act. Thank the opossum for providing some defense for us too: They eat venomous snakes and ticks, gobbling up to 4000 insects a week.

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Animals
Sploot 101: 12 Animal Slang Words Every Pet Parent Should Know
iStock
iStock

For centuries, dogs were dogs and cats were cats. They did things like bark and drink water and lay down—actions that pet parents didn’t need a translator to understand.

Then the internet arrived. Scroll through the countless Facebook groups and Twitter accounts dedicated to sharing cute animal pictures and you’ll quickly see that dogs don’t have snouts, they have snoots, and cats come in a colorful assortment of shapes and sizes ranging from smol to floof.

Pet meme language has been around long enough to start leaking into everyday conversation. If you're a pet owner (or lover) who doesn’t want to be out of the loop, here are the terms you need to know.

1. SPLOOT

You know your pet is fully relaxed when they’re doing a sploot. Like a split but for the whole body, a sploot occurs when a dog or cat stretches so their bellies are flat on the ground and their back legs are pointing behind them. The amusing pose may be a way for them to take advantage of the cool ground on a hot day, or just to feel a satisfying stretch in their hip flexors. Corgis are famous for the sploot, but any quadruped can do it if they’re flexible enough.

2. DERP

Person holding Marnie the dog.
Emma McIntyre, Getty Images for ASPCA

Unlike most items on this list, the word derp isn’t limited to cats and dogs. It can also be a stand-in for such expressions of stupidity as “duh” or “dur.” In recent years the term has become associated with clumsy, clueless, or silly-looking cats and dogs. A pet with a tongue perpetually hanging out of its mouth, like Marnie or Lil Bub, is textbook derpy.

3. BLEP

Cat laying on desk chair.
PoppetCloset, Flickr // CC BY-NC-ND 2.0

If you’ve ever caught a cat or dog poking the tip of its tongue past its front teeth, you’ve seen a blep in action. Unlike a derpy tongue, a blep is subtle and often gone as quickly as it appears. Animal experts aren’t entirely sure why pets blep, but in cats it may have something to do with the Flehmen response, in which they use their tongues to “smell” the air.

4. MLEM

Mlems and bleps, though very closely related, aren’t exactly the same. While blep is a passive state of being, mlem is active. It’s what happens when a pet flicks its tongue in and out of its mouth, whether to slurp up water, taste food, or just lick the air in a derpy fashion. Dogs and cats do it, of course, but reptiles have also been known to mlem.

5. FLOOF

Very fluffy cat.
J. Sibiga Photography, Flickr // CC BY-NC-ND 2.0

Some pets barely have any fur, and others have coats so voluminous that hair appears to make up most of their bodyweight. Dogs and cats in the latter group are known as floofs. Floofy animals will famously leave a wake of fur wherever they sit and can squeeze through tight spaces despite their enormous mass. Samoyeds, Pomeranians, and Persian cats are all prime examples of floofs.

6. BORK

Dog outside barking.
iStock

According to some corners of the internet, dogs don’t bark, they bork. Listen carefully next time you’re around a vocal doggo and you won’t be able to unhear it.

7. DOGGO

Shiba inu smiling up at the camera.
iStock

Speaking of doggos: This word isn’t hard to decode. Every dog—regardless of size, floofiness, or derpiness—can be a doggo. If you’re willing to get creative, the word can even be applied to non-dog animals like fennec foxes (special doggos) or seals (water doggos). The usage of doggo saw a spike in 2016 thanks to the internet and by the end of 2017 it was listed as one of Merriam-Webster’s “Words We’re Watching.”

8. SMOL

Tiny kitten in grass.
iStock

Some pets are so adorably, unbearably tiny that using proper English to describe them just doesn’t cut it. Not every small pet is smol: To earn the label, a cat or dog (or kitten or puppy) must excel in both the tiny and cute departments. A pet that’s truly smol is likely to induce excited squees from everyone around it.

9. PUPPER

Hands holding a puppy.
iStock

Like doggo, pupper is self-explanatory: It can be used in place of the word puppy, but if you want to use it to describe a fully-grown doggo who’s particularly smol and cute, you can probably get away with it.

10. BOOF

We’ve already established that doggos go bork, but that’s not the only sound they make. A low, deep bark—perhaps from a dog that can’t decide if it wants to expend its energy on a full bark—is best described as a boof. Consider a boof a warning bark before the real thing.

11. SNOOT

Dog noses poking out beneath blanket.
iStock

Snoot was already a dictionary-official synonym for nose by the time dog meme culture took the internet by storm. But while snoot is rarely used to describe human faces today, it’s quickly becoming the preferred term for pet snouts. There’s even a wholesome viral challenge dedicated to dogs poking their snoots through their owners' hands.

12. BOOP

Have you ever seen a dog snoot so cute you just had to reach out and tap it? And when you did, was your action accompanied by an involuntary “boop” sound? This urge is so universal that boop is now its own verb. Humans aren’t the only ones who can boop: Search the word on YouTube and treat yourself to hours of dogs, cats, and other animals exchanging the love tap.

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Animals
Carnivorous Hammerhead Flatworms Are Invading France

It’s no hammerhead shark, but the hammerhead flatworm has become a real menace in France. Or at least a menace to earthworms, as Earther reports.

Believed to be an invasive species from Asia, the hammerhead flatworm was only recently recorded in France, as is documented in a new study (titled "Giant worms chez moi!") published in the journal PeerJ. However, based on reports, photographs, and videos sent in by citizens across the country, scientists determined the pests have gone undetected for nearly 20 years. This came as a shock, especially because the worms can measure more than a foot in length.

In recent years, three species of the carnivorous worm have quietly taken over French gardens and have even been spotted in metropolitan areas. Some species immobolize their prey with tetrodotoxin, the same powerful neurotoxin that makes pufferfish so poisonous. The worms secrete digestive enzymes, allowing them to dissolve earthworms and slugs their size.

Jean-Lou Justine, co-author of the study, says their eating habits are a concern. "Earthworms are a major component of the soil biomass and a very important element in the ecology of soils," Justine tells Earther. "Any predator which can diminish the populations of earthworms is thus a threat to soil ecology."

Archie Murchie, an entomologist who was not involved in the study, told The Washington Post that the worms will continue to spread in step with global trade. The worms were also seen in overseas French territories, including one worm with a blue-green hue that is probably a newly detected species, Murchie tells the newspaper.

[h/t Earther]

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