Snakes might seem scary to some people, but they are truly fascinating creatures! Imagine moving around without any legs—how do they do it? Let’s dive into the world of snakes and discover their secrets.
Snakes are found almost everywhere in the world, except for a few places like Ireland. Scientists believe that snakes evolved from four-legged lizards during the Jurassic Period, about 150 million years ago. These ancient lizards lost their legs to better navigate narrow underground burrows, where legs would have been a hindrance.
Recently, a creature called Tetrapodophis amplectus was discovered, providing a “missing link” between lizards and snakes. This ancient animal lived during the Cretaceous period in what is now South America. It had a long body, small tail, and four limbs used for grabbing prey. Interestingly, some modern snakes, like pythons and boa constrictors, still have tiny leg bones, a reminder of their evolutionary past.
Without legs, snakes have developed several unique ways to move. Their scales are not just for show; they act like hooks, helping snakes slither across different surfaces. Originally, scientists thought scales were only useful on rough surfaces like rocks and tree bark, but they also help snakes grip smooth surfaces and even sand.
Large snakes, such as pythons and boa constrictors, can move in a straight line using a method called rectilinear locomotion. They lift their undersides to grip and push off the ground with their scales. Other snakes use segmented muscles to glide over surfaces in a twisting motion, known as lateral undulation. This wave-like motion helps them move forward in an S-shape, using fixed points in their environment to push off and advance.
If there aren’t enough resistance points, snakes might use a sidewinding motion. This technique is similar to lateral undulation but happens sideways, with only two parts of the snake’s body touching the ground at any time. Sidewinding is incredibly fast, allowing snakes to reach speeds of up to 18 mph!
Snakes can also climb trees using concertina locomotion. They stretch out their heads and scrunch up their bodies behind them, much like an accordion. Unlike lateral undulation, their muscles move all at once rather than in a sequence.
One of the most amazing snake movements is performed by the flying snake, Chrysopelea. These snakes can climb trees and jump from branch to branch. Before taking off, they shape their bodies into a J-shape and then launch themselves into the air. While airborne, they use lateral undulation to stabilize and glide gracefully before landing.
Instead of fearing snakes, we should appreciate their incredible abilities. Many snakes are harmless to humans, yet our fear of them remains strong. Understanding how they move and adapt can help us see them as the remarkable creatures they truly are.
Research the evolutionary history of snakes and create a timeline that highlights key events, such as the transition from four-legged lizards to modern snakes. Use drawings or digital tools to illustrate each stage and present your timeline to the class.
Conduct an experiment to understand how snakes move. Use a long piece of fabric or a rope to simulate a snake’s body. Try different methods of movement, such as lateral undulation and sidewinding, and observe which is most effective on various surfaces. Record your findings and discuss them with your classmates.
Imagine you are designing a habitat for a snake in a zoo. Consider the snake’s movement and climbing abilities. Create a model or drawing of your habitat, ensuring it includes elements that allow the snake to demonstrate its unique locomotion techniques. Present your design to the class and explain your choices.
Watch videos of different snakes moving in their natural habitats. Take notes on the types of movement you observe, such as rectilinear locomotion or concertina movement. Share your observations with the class and discuss how these movements help snakes survive in their environments.
Create a campaign to educate others about the fascinating world of snakes and reduce fear and misconceptions. Design posters, brochures, or a short video highlighting interesting facts about snake evolution and movement. Share your campaign materials with your school or community.
Here’s a sanitized version of the transcript:
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Snakes—why did it have to be snakes? Because they’re fascinating!
Hey everyone, Julia here for DNews. While some people are absolutely terrified of snakes, I actually really love them. They are some of the most interesting animals on this planet. Just think about how they move without any legs!
To understand that, we first need to look at their evolutionary history. Snakes are found on every continent and in almost every country, except famously Ireland. A study published in the Journal of Vertebrate Paleontology suggests that snakes likely evolved from a four-legged lizard during the Jurassic Period, around 150 million years ago. Researchers believe they lost their legs to adapt to moving in narrow underground burrows, as legs may have hindered their movement.
Recently, the journal Science identified a so-called “missing link” between lizards and snakes. Tetrapodophis amplectus, which lived during the Cretaceous period in what is now South America, is thought to be a distant cousin of modern snakes. These creatures had long bodies, small tails, and four limbs used for grasping prey. Even today, you can still see vestigial leg bones in some snakes, like pythons and boa constrictors.
Without legs, snakes have evolved several clever ways to move. A study published in the Proceedings of the National Academy of Sciences found that snake scales serve more purposes than just aesthetics. Scales act like hooks to help snakes slither across various surfaces. Researchers previously thought scales helped snakes move over rough surfaces like rocks and tree bark, but they can also grip smooth surfaces and fine grains of sand. Some snakes can even move using just their belly scales.
Large snakes, such as pythons and boa constrictors, can move in a straight line by lifting their undersides to grip and push off the ground using their scales. This movement is known as rectilinear locomotion. Other types of snakes use segmented muscles designed for slithering, allowing them to glide over surfaces in a twisting or oscillating motion. The typical snake slither you might be familiar with is called lateral undulation, where they move their segmented muscles in a specific, sequential pattern. This wave-like motion propels the snake forward in an S-shape, using fixed points in the environment, like rocks or depressions, to push off and move ahead.
If the environment lacks these resistance points, a snake might use a sidewinding motion, aptly named the sidewinder. This movement is similar to lateral undulation but occurs sideways, with only two points of the snake’s body touching the ground at any time, making it an incredibly fast way to travel. In fact, a sidewinder can reach speeds of up to 18 mph.
Snakes can also climb trees using a method called concertina locomotion. They stretch out their heads and scrunch up their bodies behind them, similar to an accordion. Unlike lateral undulation, their muscles move all at once rather than in a sequence.
One of the most remarkable examples of snake movement is Chrysopelea, also known as the flying snake. These snakes can not only climb trees but also jump from branch to branch. According to a study published in the journal Integrative and Comparative Biology, when Chrysopelea prepares for take-off, it contorts its body into a J-shape before thrusting off the branch to become airborne. In the air, it uses lateral undulating motion to stabilize itself and glide gracefully before landing.
So rather than being afraid of snakes, let’s appreciate how incredible flying snakes are! Even though many snakes are harmless to humans, our fear of them remains strong. Why are we so afraid of snakes? Amy explores that in this episode right here.
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This version maintains the informative content while removing any informal language and exclamations that may be considered inappropriate.
Snakes – Long, legless reptiles that are part of the suborder Serpentes, known for their ability to slither and their diverse habitats. – Snakes have evolved to live in a variety of environments, from deserts to rainforests.
Evolution – The process by which different kinds of living organisms develop and diversify from earlier forms over generations. – The evolution of birds from dinosaurs is a fascinating example of how species can change over time.
Lizards – Reptiles that typically have four legs, external ear openings, and movable eyelids, belonging to the order Squamata. – Lizards often bask in the sun to regulate their body temperature.
Movement – The act or process of changing position or place, often essential for survival in animals. – The movement of fish in schools helps protect them from predators.
Scales – Small, rigid plates that cover the skin of reptiles and fish, providing protection and aiding in movement. – The scales on a snake’s body help it move smoothly across the ground.
Locomotion – The ability of an organism to move from one place to another, often using specialized structures. – Birds have adapted wings for locomotion, allowing them to fly long distances.
Muscles – Tissues in the body that have the ability to contract, enabling movement and maintaining posture. – The muscles in a cheetah’s legs are specially adapted for rapid acceleration.
Climbing – The action of ascending or moving upward, often using limbs or specialized structures. – Geckos are known for their exceptional climbing abilities, thanks to the tiny hairs on their feet.
Flying – The ability to move through the air using wings, a trait seen in birds, bats, and some insects. – Flying allows birds to migrate over long distances to find food and suitable climates.
Adaptations – Changes in an organism’s structure or behavior that improve its chances of survival in its environment. – The thick fur of polar bears is an adaptation to the cold Arctic climate.
