Is that a dragon? Nope! Explore our Thorny Devil facts showing the unique traits of the Moloch horridus, a small reptile native to the Australian outback. Its dragon-like exterior, featuring approximately 600 conical spines, has captured everyone's attention.
Like many other lizards, the Thorny Devils are masters of disguise. These tiny dragons also sport a spiny false head and a hilarious walk, both vital for survival. Are you curious why? Step into our thorny devil facts and expand your reptile knowledge.
The thorny dragon–the only species in the genus Moloch–lives in arid areas of western Australia. They have a dense layer of conical spines, a defense against predators in the harsh desert. These spines grow from the belly to the head and are a prime example of evolution at work.
The Thorny Devil is broad and flat, and its head is wider than its body length. The skin color is a mixture of yellow and reddish-brown, a natural camouflage, allowing the Thorny Devil to fool predators and prey.
The Thorny Devil's scientific name, Moloch horridus, alludes to the ancient Canaanite deity and human sacrifice god featured in John Milton's poem "Paradise Lost." The first part of its name, 'Moloch,' refers to a god of human sacrifice, a fitting comparison to the thorny dragon, which looks like a hideous beast.
Meanwhile, the Latin word 'Horridus' translates to 'rough, 'bristly, or 'dreadful.' It describes the Thorny Devil's exterior, covered in sharp, thorny scales. Despite its name, invoking a devil lizard, the Thorny Devil's diet comprises mainly ants and poses no danger to other animals.
Over the years, they gained many names—mountain devil, thorny lizard, thorny dragon, thorny toad, and Moloch.
Australia's Thorny Devil can consume up to 3,000 ants in one sitting. The devils' feeding strategy involves tracking the ants' trail and deploying their long sticky tongues to capture them.
Like a plant, thorny devils can absorb water through their skin rather than their mouths3. How can they achieve this?
Their skin has a complex matrix of grooves and scales which can absorb water through capillary action. When it comes into contact with moisture, such as dew or moist sand, liquids can travel upwards against gravity. This process is similar to how plants transport water to their leaves.
In addition to providing hydration, this bizarre adaptation also helps the lizard regulate its body temperature in extreme desert conditions. The lizard can burrow into the sand to access cooler, damp layers below, making the harsh environment more bearable.
Like other desert animals, thorny devils evolved to have sandy-hued skin to avoid predators and sneak up on prey in the arid terrains. Aside from their colors, their spiky exterior matches the ruggedness of their habitat.
Moreover, the thorny devil's mimicry changes depending on the current temperature. They darken their color during cooler mornings, allowing for better thermoregulation. As the sun peaks, the lizard lightens its color, preventing overheating.
Evolution did its thing again by giving another animal spikes! These dragon-like lizards feature sharp protrusions made of keratin, similar to our hair and nails. These spikes prevent attacks from predators. Although they don't actively attack, this evolutionary wonder is a convincing deterrent. Other creatures with spiky defense mechanisms are hedgehogs and echidnas.
As scary as they look, they look amusing when moving. The following thorny devil fact discusses its purpose.
The Thorny Devil has a unique gait that people liken to a mechanical toy, featuring a high, stilted lift of its body with each step as if walking on invisible stilts2. Why do they walk that way?
Their unusual walk is a survival mechanism. The jerky, irregular motion fools predators into thinking they have spotted wind-blown debris or a tumbling leaf rather than potential prey. What a simple but clever move!
Furthermore, it is another adaptation to its harsh environment. The lizard takes careful and measured steps, possibly to avoid sinking into the soft desert sand or minimizing contact with the hot ground.
But don't get fooled! Despite its slow pace, these spiky lizards can break into a surprising sprint when it senses danger.
The thorny devil fact below mentions another unique survival mechanism.
The Thorny Devil has evolved a peculiar feature–a pseudo-head–situated between the lizard's actual head and its humped back. Their false heads are a dummy made of soft tissue and lacking sensory abilities1.
However, when danger approaches, the Thorny Devil bows its real head low and flicks up the pseudo-head, tricking potential predators into targeting the decoy. This trick allows the horned lizard to escape amidst the confusion.
Female thorny devils lay around three to ten eggs in a nesting burrow beneath the shifting sands of their arid habitats, where they remain safe and warm. Rather than helpless neonates, the eggs hatch into fully formed and self-sufficient lizards with characteristic spikes that protect them from predators. Moreover, they resemble their parents in every way.
Thorny Devil hatchlings look intimidating due to their solitary lifestyle. Like adults, they also eat ants, which they consume in large quantities to promote their growth.
Additionally, these hatchlings mimic the adults' bobbing walk and can change colors to protect themselves from predators. However, their path to maturity is challenging. It takes two years of battling the elements and overcoming various obstacles in the wild.
The Thorny Devils have stable populations in their native habitat in Australia, thus their IUCN classification of 'Least Concern.'
There is little to no urban expansion and farming activities in the arid western and central Australia. Thanks to these untouched landscapes, these regions are ideal sanctuaries for the thorny lizards. Additionally, their low demand in the pet trade keeps their population stable, unlike other lizards.
But we should not be negligent. Even if they have a "least concern" status, we must consistently care for these exceptional creatures. Climate change remains a potential risk factor, and we must continue monitoring population trends and protecting their habitats.
Remember to share these thorny devil facts with fellow reptile lovers.
Related: To further explore the animal kingdom, check out some of the other animals that start with T.
Bell, C. J., Mead, J. I., & Swift, S. L. (2009). Cranial osteology of Moloch horridus (Reptilia: Squamata: Agamidae). Records of the Western Australian Museum, 25(2), 201.
Bush, B., Maryan, B., & Browne-Cooper, R. (2007). Reptiles and frogs in the bush: Southwestern Australia. University of Western Australia Press. pp. 46, 65, 158. ISBN 978-1-920694-74-6.
Knight, K. (2016). How thorny devils tap damp sand to slake thirst. The Journal of Experimental Biology.