40 Fun Facts About Bearded Dragons

In which Disney film were bearded dragons cast as the deadly yellow-spotted lizards of Camp Green Lake?

Holes used fourteen bearded dragons, four of them for the main parts and the rest as background lizards. Louis Sachar wrote the screenplay from his own novel.

In a well-known experiment, what did most bearded dragons manage to do after watching a trained lizard do it first?

Most watchers went on to open a door themselves after seeing a trained lizard do it to reach food. The result showed that bearded dragons can learn by copying their own kind.

Which snake-like feature did researchers find in bearded dragons' mouths, though a bite does people no lasting harm?

Venom glands of a primitive kind were reported in bearded dragons by a 2006 study of lizards and snakes. What the dragons use them for is still not understood.

Which nest condition can turn genetically male bearded dragon embryos into fertile, egg-laying females?

High temperature in the nest, typically above 32 °C, overrides the embryo's sex chromosomes. These sex-reversed mothers are fertile and can lay nearly twice as many eggs as other females.

Australia banned wildlife exports in the 1960s, so how did most pet bearded dragons' ancestors leave?

Smuggling carried the founding animals out between 1974 and 1990, well after the export ban. By the early 1990s a captive-bred population had taken hold in the global pet trade.

Which gesture does a low-ranking bearded dragon use to signal submission to a dominant rival at a basking site?

Waving a forearm in a circle usually defuses the confrontation. The dominant animal makes its own point by bobbing its head and inflating its beard.

What colour does a male bearded dragon's throat pouch often turn when he is threatened or courting a female?

Black is the classic warning shade, and the puffed-out pouch makes the lizard's jaw look larger. Both sexes have a beard, but males display it more often.

Which insects do vets warn must never be fed to bearded dragons because they are generally toxic to lizards?

Fireflies carry defensive steroids called lucibufagins, close cousins of the heart toxins found in some poisonous toads. Most predators find the beetles distasteful and leave them alone.

Bearded dragons do not vocalise, with one exception: which sound do they make when they feel threatened?

A low hiss is their only call, so nearly all communication happens through posture, colour displays and gestures. A cornered dragon will puff up and bluff long before it bites.

Which bacteria, carried by many healthy bearded dragons, is why owners are told to wash their hands after handling?

Salmonella lives in the gut of many reptiles that show no sign of illness and is shed in their droppings. Pet turtles are the reptiles most often blamed for infecting children.

Which term, coined for cold-blooded animals, describes a bearded dragon's winter months of dormancy?

Brumation differs from a mammal's hibernation: the lizard goes months without eating but still stirs now and then for water. Once it ends, males set off to find a mate.

Which nutrient do bearded dragons make with the help of UVB light, letting them absorb the calcium in their food?

Vitamin D3 forms only under UVB, which is why every pet bearded dragon needs a special lamp. The bulbs fade with age, so vets suggest replacing them about every six months.

Which illness, probably the commonest in pet bearded dragons, is a UVB lamp fitted to prevent?

Metabolic bone disease sets in when the body, starved of calcium, starts drawing it from the skeleton instead. Signs include tremors, a swollen lower jaw and jerky movements.

Which salad vegetable should bearded dragons eat only sparingly, because its oxalates block calcium absorption?

Spinach, like Swiss chard and beet greens, is rich in oxalates that bind calcium before the lizard can use it. Collards and dandelion greens are safer everyday staples.

As young bearded dragons grow into adults, their diet shifts away from insects and towards which kind of food?

Plants take over as the lizards mature, while fast-growing youngsters are mainly insect eaters. Vets suggest a pet's diet overall should be about half plant and half insect, shifting with age.

Which Australian relative of the bearded dragon, a member of the same family, can sprint upright on its hind legs?

The frilled lizard also bluffs like its cousin, spreading a wide ruff of skin around its neck where the bearded dragon puffs out a spiny throat. It runs on two legs to hunt or to escape.

Which man-made perches do Australians often spot wild bearded dragons basking on, alongside stumps and boulders?

Fence posts give a climbing lizard height, sun and a view of predators, prey, rivals and mates. One male was recorded staying up the same tree for three weeks.

Keepers are told never to feed a young bearded dragon an insect wider than the gap between which body parts?

Its eyes set the limit because prey that is too large can cause impaction, a dangerous blockage of the gut. Older dragons cope better with larger insects.

Which bedding, sold as digestible, do vets say to avoid in a bearded dragon tank as it can block the intestines?

Calci-sand is marketed as safe to swallow, yet it can still plug the intestines. Vets prefer newspaper or other paper bedding, which is non-toxic and easy to replace.

What is a basking bearded dragon doing when it sits calmly with its mouth agape?

Cooling off is the aim: moisture evaporating from the mouth lining chills the blood passing through the head. The same gaping mouth, paired with a puffed beard, doubles as a threat display.

Which organ on the top of a bearded dragon's head helps regulate its hormones and body warmth?

The parietal eye, nicknamed the third eye, sits in the centre of the forehead. Snakes are the odd ones out among the lizards' close kin: they have no such organ.

Which practice has keepers feed crickets nutritious food within 12 hours of offering them to a bearded dragon?

Gut loading turns each insect into a parcel of extra nutrients for the lizard that eats it. Vets pair it with dusting, where the prey is coated in calcium powder.

Which heated tank accessory do vets call dangerous because bearded dragons that sit on it too long get burned?

Hot rocks, also sold as sizzle rocks, get very hot and are notorious for burning reptiles. Vets say heat should come from above and outside the enclosure instead.

Which everyday material blocks the UVB rays a bearded dragon needs, so a UV lamp must never shine through it?

Glass filters out the UVB wavelengths, so a sunny windowsill does little for an indoor lizard. Vets encourage supervised time in direct outdoor sunshine when the weather is warm.

Which Australian bush poet is honoured in the scientific name of Rankin's dragon, a dwarf bearded dragon species?

Henry Lawson, often called Australia's greatest short story writer, lives on in the name Pogona henrylawsoni. In 1922 he became the first Australian writer granted a state funeral.

Which vast, almost treeless stretch of Australia's southern coast is the only home of one bearded dragon species?

The Nullarbor Plain takes its name from the Latin for no tree, and the Nullarbor bearded dragon lives nowhere else. The species was first described in 1976.

In a University of Padova test, bearded dragons offered equal meals on two different plates mostly chose which one?

The smaller plate won, showing the lizards fall for the Delboeuf illusion, in which a portion looks bigger on a little dish. It was the first evidence of the effect in a reptile.

Bearded dragons belong to the suborder Iguania; which other well-known lizards are grouped there with the iguanas?

Chameleons round out a suborder that also holds a host of New World lizards. Geckos, skinks and monitors sit on other branches of the reptile family tree.

Which name do breeders give bearded dragons with no scales at all, which lose water twice as fast as wild types?

Silkback dragons hatch when two smooth-skinned leatherbacks are paired. Their fragile skin dries out quickly, so they need special care with light and humidity.

Which ability lets a female bearded dragon lay two fertile clutches of eggs after only a single mating?

Storing sperm in the oviduct lets her fertilise a second clutch with no male around. In captivity, a single female has laid up to four clutches in one season.

What does a female bearded dragon do with her eggs once she has laid the clutch in a burrow she dug herself?

She buries and leaves them, back-filling the entrance to hide the nest, and the hatchlings get no care at all. A clutch usually holds between 11 and 30 eggs.

What sets a bearded dragon's tail apart from a gecko's when a predator grabs hold of it?

It cannot break off and regrow the way a gecko's or a skink's can. That holds for dragon lizards as a family, though a few species show a little regeneration.

The body colours of wild central bearded dragons normally match the colour of what in their home range?

The soil sets the palette, which is why the species comes in shades of red, brown and yellow. The eastern bearded dragon, by contrast, is mostly grey.

Bearded dragons breathe using the muscles between their ribs because they lack which structure found in mammals?

A diaphragm separates the chest from the abdomen in mammals, but a bearded dragon has none. Its heart differs too, with three chambers rather than a mammal's four.

During light rain, a central bearded dragon may rear up on its back legs with its head sloping down to do what?

Drink the runoff: water streams forward over the body to the snout, where the lizard licks it up. One dragon was watched holding the pose for 20 to 30 minutes.

Which waste product forms the white part of a bearded dragon's droppings, where mammals would pass liquid urea?

Uric acid is the main waste from breaking down protein, and passing it as a near-dry paste keeps water loss low. Birds get rid of their nitrogen waste the same way.

Which scent-marking bumps, found in a row on a bearded dragon's underside, are larger in adult males than in females?

Femoral pores show up as a row of waxy bumps, and their size is one way to tell the sexes apart. Males also have larger heads and darker beards.

Which winged insects made up most of the prey in the stomachs of wild central bearded dragons in one study?

Termites in their winged swarming stage made up 95% of the prey items and over half the food by dry weight, a feast on offer for only part of the year. Dragons are opportunists that eat whatever is plentiful.

Bearded dragons belong to which Old World lizard family, whose members are often simply called dragons?

Agamidae spans hundreds of species across Africa, Asia, Australia and a corner of southern Europe. Its members carry their teeth on the rim of the jaw rather than the inner side.

Which French naturalist, called the founding father of palaeontology, first described the eastern bearded dragon?

Georges Cuvier named the species in 1829, almost a century before the central bearded dragon was described. That later job fell to the German zoologist Ernst Ahl in 1926.