10 Unfurled Facts About Frilled Dragons

Flamboyant and reclusive in equal measure, this iconic lizard can bluff like a poker champion. Here’s a brief introduction to the weird world of frilled dragons.


Frilled dragons are native to the semiarid forests and grassy woodlands of northern Australia and southern New Guinea, and if you know what you’re looking for, the lizards can be easy to spot: Just look to the trees, where the creatures spend 90 percent of their lives. Frilled dragons press themselves vertically against a trunk and tend to stick their necks out at a 45-degree angle, making the lizards quite recognizable from afar. Once a predator wanders by, the dragon rests its chin against the bark, its gray-to-brown scales acting as camouflage.


Like many lizards, frilled dragons have an insect-based diet supplemented with the occasional rodent or small reptile. But mealtime can be perilous. Though they spend much of their time safe in trees, hunting generally takes place on solid ground, where the dragons have a greater risk of getting hunted themselves. In the face of danger, a dragon’s first instinct is to either bolt toward the nearest tree or lie motionless. But if neither seems like an option, the reptile fights back with an underrated tool: deception.

The frilled dragon is named after the twin frills on either side of its head, which flare open when something invades the animal’s personal space. Ideally, this bluff will make the lizard appear twice as large as it truly is. From nose tip to tail tip, adult frilled dragons have a maximum length of 33 inches, but their foot-wide frill helps them look much, much bigger.

To enhance the performance, our dragon may hiss, rear up on two legs, and run at the marauder. Of course, some onlookers don’t buy this charade. If its big show doesn’t scare away the audience, the lizard will take off.


Your tongue has an anchor called the hyoid bone, a small, u-shaped structure atop the Adam’s apple. Frilled dragons have two. They're long and rod-like. By flexing the muscles connected to these hyoids, a dragon can expand or contract its frill. For anatomical reasons, it can only pull off the frill-opening motion while also widening its jaws.


It’s a cute nickname that’s inspired by the way frilled dragons run. When the reptiles rear up on their hind legs and zip around in bipedal fashion, they wheel both legs in a broad, circular motion.

Plenty of other saurians are known to move like this once in a while; when the big-headed, North American collared lizard does so, it almost looks like a miniature T. rex. Meanwhile, the basilisks of Central and South America are also called “Jesus Christ lizards” because they can stand up and run across bodies of water.

Why do lizards like frilled dragons rear up to run instead of cruising along on all fours? To find out, in 2008 an international research team set up a reptile gymnasium. They gathered specimens that represented 16 different types of semi-bipedal lizard, including the frilled dragon. Afterward, the team placed their subjects on miniature treadmills.

Footage of those workouts revealed surprising results. Apparently, the bipedal running style is less energy efficient than its quadrupedal alternative. However, many of the species they tested were able to accelerate faster on two legs than on four. In nature, a quick first step can be critical. 


Introduced in 1966, the 2-cent coin remained in circulation until 1992. On the front was a profile of Queen Elizabeth II; on the back, a frilled dragon with its tail curling and mouth agape. These coins became a huge collectors item … in Japan. After the lizard featured in a Japanese TV ad in the mid-'80s, sales of the coin skyrocketed to 20,000 to 30,000 a day with 2-cent coins going for 43 cents (100 yen) each.


In Queensland, the lizards usually have yellow or whitish frills, while those that live in Western Australia and the North Territory have red and orange ones instead. According to Thomas Merkling of Australian National University (ANU), certain insects contain pigments that can alter the shade of a lizard’s frill. If these prey items are consumed regularly, the appendages will become darker in color.

On top of looking great, vibrant colors might offer a combat advantage. In 2013, scientists from ANU and Macquaire University (MU) examined numerous fights between male dragons. They found that in 90 percent of these squabbles, victory went to the lizard whose frill was brighter. “Surprisingly, traits such as frill size, head size, and bite force did not predict contest outcome,” said MU biologist Martin Whiting. “Instead, males with brighter and more colorful frills were more likely to dominate opponents and take gold.”


Sometimes known as “Darwin’s bulldog,” Thomas Henry Huxley (1825–1895) was a passionate defender of evolutionary theory. A respected anatomist, he was among the first scientists to ever suggest that there might be a link between birds and reptiles.

Huxley found a supporter in Johan Ludwig Gerard Krefft (1830–1881). In 1870, Krefft—then the curator of Australia’s National Museum—told the Sydney Morning Herald that he’d written Huxley about the frilled dragon, describing it as “a lizard which would squat on its hind legs, and even hop in a manner not unlike a bird.” Could this species help prove Huxley’s hunch?

Huxley asked another scientist to investigate further.Huxley’s recruit was marine biologist William Saville-Kent (1845-1908). After scrutinizing the anatomy and behavior of the lizard, Saville-Kent concluded that neither its skeleton nor habits were all that bird-like—much to his own disappointment. Still, history has vindicated Huxley: A tidal wave of evidence now indicates that our feathered friends are descended from those most celebrated of reptiles, the dinosaurs.


Eggs kept at 26°C overwhelmingly yield female babies, while clutches that are continuously exposed to a temperature of 29°C produce males and females in about equal measure. Biologists call this phenomenon temperature-dependent sex determination, or TSD. It’s something that a great many reptiles—including alligators and red-eared slider turtles—have to contend with.


The agamid family includes more than 350 species that come in every oddball shape you could ask for. Consider, for example, the aptly-named “flying dragons,” which use their elongated ribs and specialized skin flaps to glide between trees. Australia’s thorny devils are burrowing, color-changing ant-gobblers that are covered with spikes. Over in the Philippines, you may encounter a gang of large, semiaquatic omnivores known as sailfin lizards. And pet stores all over the world now stock the ever-popular bearded dragons. When threatened, these little creatures expand a pouch on the underside of their throat that’s covered in tiny spines.  Fortunately, captive-bred “beardies” tend to be quite docile.


Never underestimate a genetically-modified dinosaur. After killing the electric fences in Jurassic Park, the vile Dennis Nedry (played by Seinfeld’s Wayne Newman) gets his comeuppance from a poison-spewing Dilophosaurus. Right before it pounces on him, the beast unfurls an oversized, retractable frill—which strongly resembles the namesake attribute of a certain Australian lizard.

In reality, there’s no evidence that Dilophosaurus—or any other dinosaur—had such an apparatus. Still, the man who originally named this animal back in 1954 didn’t seem to mind Jurassic Park’s little inaccuracies. “It was quite a thrill to see Dilophosaurus as an actor,” raved paleontologist Sam Welles. Though he admitted that the dinosaur’s neck vertebrae would have been incompatible with a frilled dragon-style hood, Welles dismissed his own critique as a minor point. “I enjoyed the movie thoroughly,” he said.

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

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.


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.


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.


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.


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.


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.


Dog outside barking.

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.


Shiba inu smiling up at the camera.

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.”


Tiny kitten in grass.

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.


Hands holding a puppy.

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.


Dog noses poking out beneath blanket.

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.

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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