At first glance, the Basilisk Lizard might seem like an ordinary reptile, but it has a unique ability that seems almost miraculous. This lizard can run on water! Known as the “Jesus Christ Lizard,” it can dash across the water’s surface, defying gravity and challenging our understanding of movement.
Despite its impressive skill, the Basilisk Lizard is not a fierce predator. It is vulnerable to many threats, including birds, snakes, and fish. To avoid these predators, the lizard relies on its ability to blend into its surroundings, camouflaging itself among leaves and branches. However, when danger approaches, it uses its incredible water-walking ability to escape.
So, how does the Basilisk Lizard manage to run on water? Researchers have studied this fascinating ability using high-speed cameras. The lizard’s hind legs move in a unique way, similar to a bicycle’s pedals, allowing it to create air pockets on the water’s surface. This process involves three phases: the slap, the stroke, and the recovery.
During the slap phase, the lizard’s foot hits the water, creating an air pocket. In the stroke phase, the lizard pushes against this pocket to propel itself forward. Finally, in the recovery phase, it quickly pulls its foot out before the pocket collapses. This cycle repeats rapidly, allowing the lizard to “walk” on water.
Interestingly, the ability to run on water is more effective in smaller Basilisk Lizards. Smaller lizards can generate enough force to stay above the water, while larger ones struggle more. This means that younger, lighter lizards are better at this miraculous feat.
While the idea of humans walking on water is intriguing, it’s not possible on Earth due to gravity and our body weight. Researchers have calculated that to achieve this, a person would need to run extremely fast and wear large fins. However, in a place with lower gravity, like the moon, it might be possible with some adjustments.
The Basilisk Lizard’s unique movement has inspired scientists and engineers to create robots that can move between land and water. These robots could be useful for rescue missions, exploring dangerous terrains, and even studying other planets.
Some robots are designed with blade-like legs to mimic the lizard’s movement, allowing them to navigate challenging environments. Others are inspired by various animals, combining features to create versatile machines capable of walking on water, rolling, and swimming.
As technology advances, researchers are exploring ways to make robots more adaptable. By using neural networks, robots can learn to handle different terrains and obstacles on their own, making them more efficient and versatile.
The Basilisk Lizard’s incredible ability to walk on water not only fascinates scientists but also inspires innovations in robotics, showing us how nature can lead to groundbreaking technological advancements.
Use clay or other craft materials to create a model of the Basilisk Lizard. Pay attention to its unique features, such as its long toes and slender body. This will help you understand how its physical characteristics contribute to its ability to run on water.
Conduct a simple experiment to understand the concept of water walking. Use small objects like paper clips or leaves to see how they float or sink. Discuss how the Basilisk Lizard’s movement might create air pockets to support its weight on water.
Try a camouflage activity by hiding small objects in a natural setting, like a garden or park. See how well you can blend them into the environment. This will give you insight into how the Basilisk Lizard uses camouflage to avoid predators.
Work in groups to design a simple robot or model that can mimic the Basilisk Lizard’s water-walking ability. Use materials like cardboard, rubber bands, and small motors. Present your design and explain how it could be used in real-world applications.
Research other animals that have inspired robotic designs. Create a presentation on how these animals’ unique abilities have been translated into technology. Share your findings with the class to explore the connection between biology and engineering.
Here’s a sanitized version of the provided YouTube transcript:
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This little reptile may look like a normal lizard, but it’s actually a creature capable of something that some would define as a miracle. In the blink of an eye, it takes off and dashes away, sprinting on top of the water. Meet the Basilisk Lizard, the water-walking dragon that seems to defy gravity and challenge much of what we know about movement and locomotion.
Unlike its mythical counterpart, Basilisk lizards aren’t in the business of causing death with a single glance. In fact, real-life basilisks are not very formidable and are quite vulnerable to predators such as large birds, snakes, and fish. They generally lay motionless, and their cryptic coloration allows them to blend in with the brown hues of branches or dead leaves on the forest floor, or the deep greens of foliage higher up in the trees.
When threatened, however, basilisks employ one of the most creative escape strategies known in the animal kingdom. When jolted from their statue-like state, a basilisk lizard’s hind limbs spring into action, bicycling across the surface of the water and propelling the tiny lizard up to 15 feet, covering more than 10 times its own body length in a single second. Once this aquatic runner has sprinted as far as it can, it sinks down into the water, far from whatever threat caused it to move in the first place.
This seemingly miraculous escape tactic has earned the Basilisk the nickname “Jesus Christ lizard” in its homeland of Central and South America and has captured the attention of not only reptile enthusiasts but also biomechanical engineers looking to recreate this water-walking ability using adaptive robotics.
What is it about these seemingly physics-defying lizards that allows them to possess such a remarkable ability, and what might these skittish creatures teach us about walking on water ourselves? Basilisk lizards belong to the Crotaphytidae family, named for the round crests on top of their heads. This might have earned them their scientific name, Basiliscus, which translates to “little king.” These little helmeted kings belong to a much grander lineage of superpowered lizards, the Iguanians. This suborder includes some 2,000 lizards, from the fearsome frilled and spiky lizards in Australia to the flying acrobats of Southeast Asia gliding across canopies, and a colorful array of hue-shifting chameleons across different continents. But only the Basilisk Lizard can walk on water, a unique adaptation that may have come from an ancient ancestor.
The Babby Basiliscus, a 48-million-year-old lizard skull fossil, is a close relative of the Basilisk Lizard. While there isn’t a way to prove that this ancient relative was also able to walk on water, researchers do know that this ancestral species lived during a time when it would have been very useful to do so. The environment was full of early ancestors of carnivorous mammals, raptors, and even crocodiles, and being able to run on water would have definitely improved chances of survival amidst these predators.
Today, the incredible ability to walk on water remains essential for survival against snakes, predatory birds, and large mammals that would happily snack on a little lizard. They do their best to camouflage, but even the best camouflage can sometimes be discovered by the keen eyes of larger birds, the supercharged smell of snakes, and the prowling of mammals that can see in the dark. That’s when running on water comes in handy.
To fully appreciate the miracle of the Basilisk Lizard walking on water, consider how most legged animals walk on land. To describe the gait of terrestrial organisms, biomechanical researchers typically refer to the classic spring-mass model. Imagine what it’s like when you take a step to walk. After you plant your foot firmly into the ground, notice how your leg flexes slightly before you push off. This slight flexion can be compared to compressing a spring, priming it for expansion as you bounce off your leg to propel yourself forward. This bouncing gait is common in many forms of terrestrial locomotion, from the galloping of horses to the hopping of rabbits, and it’s a particularly efficient way of moving on land.
For the Basilisk Lizard sprinting across a pond, it’s easy to see that this model wouldn’t be a good fit. For such a spring system to work, the ground needs to provide enough resistance for the spring to push against. Water, however, is weak, yielding, and gives way to most pressure applied to it. Most limbs that attempt to take a step in water sink, and those that don’t, like other water walkers in the animal kingdom, typically rely on other mechanisms to stay afloat.
The water strider, for example, floats on the surface with the help of multiple long, widespread legs with waterproof hairs. The buoyancy created by these legs can support up to 15 times the insect’s weight, a useful adaptation when it rains and water drops add considerably to their body weight. Waterfowl like ducks and geese can also occasionally be seen running on water, but they are usually assisted by flight that allows them to skim the surface.
The Basilisk Lizard doesn’t have long buoyant limbs, and unlike some gliding lizards, it isn’t able to glide or fly. So how does this reptile manage such an incredible task? Using high-speed cameras, researchers have discovered just how the Basilisk Lizard does it. Instead of the classical bouncing spring model, the Basilisk’s hind limbs move in a more bicycling, piston-like fashion—a totally unique form of movement.
The piston-like movement of the Basilisk can be seen sequenced into three distinct phases: the slap, the stroke, and the recovery phase. As the name of the first phase suggests, the Basilisk Lizard first slaps the surface of the water, creating a pocket of air that keeps the lizard from sinking. It’s this same kind of air cavity-forming phase that allows us to skip tiny pebbles across the surface of a lake.
In the stroke phase, the lizard starts to propel itself forward, its leg quickly digging into the air pocket and kicking back as it pushes off the cavity formed in the slap phase. Just before the air pocket collapses and water rushes in to sink the Basilisk’s leg, it curls its toes and swiftly pulls its leg out of the air pocket before it breaks, transitioning into the next slap-stroke-recovery cycle on the other leg. In this sense, Basilisk lizards aren’t so much water walkers as they are air benders, forcing bubbles of air beneath their feet with each step.
To maintain its center of gravity during the slap phase, the lizard’s leg slightly pushes off towards the midline, while in the stroke phase, it shifts slightly laterally as it tries to right itself. This kind of wobbly transverse movement, coupled with its flailing upper limbs and a long rudder-like tail, helps the Basilisk stay balanced as it dashes across the water, giving it its characteristic goofy, almost clumsy-looking way of running.
But is this something that all Basilisk lizards can do? From the tiniest to the absolutely huge ones, is there a point at which size prevents them from running on water? A group of researchers found that smaller juvenile lizards were much more successful at running on water than larger adults, indicating that size plays a role. When they analyzed the gait mechanics of lizards weighing between 2 grams and 200 grams, they found something interesting: all of them generate more than enough force to stay on the surface of the water, but how they move changes.
Small lizards can be somewhat sloppy with their movements because at 2 grams, they can generate 225% of the force needed to maintain their center of mass. In fact, researchers say that a 2-gram lizard could carry another lizard of the same size on its back and still easily run across the water. Lizards that weigh 200 grams, on the other hand, only produce just over the amount of force needed to support their body weight. They have to avoid drag and yank their feet out of the water as quickly as possible because they’re much more likely to sink, leaving no chance for them to carry a hitchhiker on their backs.
This brings us to the next question: could humans ever do this? If we wore the world’s biggest flippers and never skipped leg day at the gym, could we generate the force necessary to walk on water? Unfortunately, not on this planet. Researchers calculated that humans would have to run at 30 m/s (67 mph) on one square meter of fins to generate the necessary force. Not even Usain Bolt could manage it. However, if we reduced gravity to only 20% of Earth’s gravity—essentially getting it to the moon’s gravity—we’d have a chance. You’d still need to wear small fins and weigh no more than 73 kg, but then it would actually be possible to walk on water. Considering there’s no water on the moon, this isn’t the most useful information, but who knows what future humans might get up to?
Until then, we’re more likely to use the Basilisk Lizard for inspiration in our machines. This simultaneously funny-looking and incredible adaptive strategy of the Basilisk Lizard has captivated the attention of researchers in the field of biomimetic robotics—scientists and engineers who take inspiration from movements in nature and emulate them with machinery. In the context of the Basilisk Lizard, this means amphibious robots designed to navigate between terrestrial and aquatic environments.
While there are already a number of species of amphibious robots coming in all shapes and sizes, many of these rely on wheels or leg mechanisms that sink into the water, while others, inspired by the water strider, rely more on buoyancy and thus move across the water considerably slower. While useful, these robotic designs don’t quite fill the niche of function that a water-running robot could provide. A fast and highly reliable robot that could transition almost instantly from land to water and back could be incredibly useful for unmanned rescue missions, research into dangerous terrain, more efficient ocean explorations, and maybe even the exploration of alien environments.
Consider some of the prototype robots inspired by the water-walking Basilisk. This blade-type crawler, developed by Yamada and Nakamura, has blade-like legs attached to a conveyor belt-like mechanism around the robot’s body. Compared to other approaches to rough terrain, this mechanism allows for a good balance between the high velocity that a wheeled vehicle provides and the adaptability that a legged robot could provide. Unlike its reptile counterpart, this blade crawler wasn’t designed for running away; this tiny robot headed straight towards danger as it was field-tested to explore volcanic areas of Mount Mihara in Japan. The Basilisk-inspired robot didn’t disappoint as it navigated seamlessly through small ponds and puddles, demonstrating the potential for unmanned observation of otherwise dangerous sites such as active eruptions.
Other projects take inspiration from nature to the extremes, like this lizard-spider-octopus-jellyfish rolling robot. You heard that right! This robot is envisioned not only to walk on water like the Basilisk Lizard but also to roll and fold up on top of the water like the Golden Wheel spider and propel itself underwater, just as we see octopuses and jellyfish do. If this wasn’t impressive enough, researchers also hope to have this robot release a swarm of other baby robots, engineered to mimic some of nature’s best water travelers. While this mind-boggling robot was initially designed for deep-sea research and ocean object identification, the authors mention that such an alien-looking robot may potentially be suited for out-of-this-world explorations in unpredictable environments beyond Earth.
The Basilisk Lizard is a prime example of how seemingly small scientific curiosities can be transformed into real-world practical applications that have the potential to save lives and provide us with a better understanding of worlds we’ve never even been to before. Our growing understanding of the Basilisk’s unique movements has allowed for a more analytical approach to recreating this remarkable ability, with researchers experimenting with dynamic folding feet and different kinds of rigid and active tails to hopefully reach a point where walking on water will be nothing out of the ordinary.
However, as researchers are starting to realize, manually programming robots to deal with various situations—such as highly variable terrain from ice to gravel to water to rocks—is time-consuming and doesn’t work that well. To truly unlock the potential of robots like the Basilisk bot, researchers are starting to use neural networks that allow the robot to learn on its own how to deal with obstacles it faces. This is undoubtedly the next significant leap in robotics, and it’s one that many find complex. The papers on the subject are dense, and understanding them can be challenging.
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This version removes any informal language, typos, and unclear phrases while maintaining the original content’s essence.
Lizard – A reptile that typically has a long body and tail, movable eyelids, and usually four legs, often studied for its unique locomotion abilities. – Scientists study the movement of a lizard to develop better robotic limbs.
Water – A transparent, odorless, tasteless liquid that forms the seas, lakes, rivers, and rain, and is the basis of the fluids of living organisms. – Engineers designed a robot that can navigate both on land and in water, mimicking the movement of aquatic animals.
Movement – The act or process of changing position or place, crucial in both biology for survival and robotics for functionality. – The movement of the robotic arm was inspired by the fluid motion of a human arm.
Predators – Animals that naturally prey on others, often influencing the evolution of defensive mechanisms in prey species. – Robotics researchers are developing drones that can mimic the hunting strategies of predators to improve search and rescue operations.
Camouflage – The ability of an organism to blend in with its surroundings to avoid detection by predators, a concept also used in robotics for stealth technology. – The robot’s camouflage technology allows it to blend into its environment, much like a chameleon.
Robotics – The branch of technology that deals with the design, construction, operation, and application of robots. – In robotics class, students learned how to program a robot to perform simple tasks.
Technology – The application of scientific knowledge for practical purposes, especially in industry, including the development of machinery and equipment. – Advances in technology have led to the creation of more sophisticated and efficient robots.
Gravity – The force that attracts a body toward the center of the earth, or toward any other physical body having mass, affecting both biological organisms and robotic designs. – Understanding gravity is essential for designing robots that can walk on different terrains.
Researchers – Individuals who conduct scientific studies to discover new information and advance knowledge in a particular field. – Researchers are exploring how insect movement can inspire new robotic designs.
Designs – Plans or drawings produced to show the look and function of an object before it is built or made, crucial in both biology for understanding structures and in robotics for creating functional machines. – The designs for the new robot were inspired by the efficient movement of a cheetah.
