Last updated on February 5th, 2022
While I was waiting at a doctor’s chamber, a program being televised on a wildlife channel caught my niece’s attention.
The program was primarily about amphibians, reptiles, and their evolution. But what got me thinking was the question asked by my ten-year-old niece, whose appointment it was.
I saw that the broadcast had shifted to alligators and crocodiles after which she asked me how the creature could swim fast in the water but only crawl or make similar awkward movements on land.
We mostly associate animals with swift action on land, but we often forget that some creatures can only crawl.
Animals that crawl on land:
- Alligators
- Snakes
- Crabs
- Seals
- Ants
- Lizards
- Octupuses
Certain animals have evolved into land crawlers naturally while others are usually forced to crawl as land isn’t entirely their natural habitat. I discovered a few of the animals that crawl on land, and some of these are as follows:
Here are seven animals that crawl on land:
1. Alligators
If you’ve observed an alligator’s body structure, you’ll see that the animal has short and stumpy legs. The tail of the animal is long, which acts as a propellant when it swims in water.
The tail helps the alligator swim forward in the water, and its swift movement makes it a deadly predator in the water.
The short legs work in unison as the predator suddenly emerges from the water and hunts its prey even from land.
But when an alligator moves on the ground, its movement becomes twisted and cumbersome, resembling a crawling movement.
You’ll find that alligators can move fast on land only when trying to avoid being hunted by a more significant predator.
Another movement belonging to their crawling motion is the ‘death roll’. The alligator spins or maneuvers its body on a longitudinal axis, which is similar to a rolling motion.
An alligator will perform this movement on land only to avoid being captured or dismember a prey that it finds difficult to be torn.
Thus, the alligator’s movement on the ground resembles that of crawling. It does so primarily because of the shape of its limbs.
2. Snakes
Snakes are usually associated with the ‘S’ like movement, but in reality, snakes can even move in straight lines.
Snakes can crawl in a straight line, and climb, all with the help of the powerful muscles attached to their ribs.
Snakes are invertebrates, which means they have an inner bone structure that allows them more freedom of movement.
They can crawl by expanding and contracting the powerful muscles of their entire body. If you observe the actions of a snake, you’ll find that it’s similar to that of a spring.
When it contracts, it reduces in shape, and as it expands, it moves forward with great force.
The entire process occurs in a matter of moments allowing the snake to crawl along with great speed.
The crawling movements of snakes are so powerful that they can use this force to move small objects from their path.
Snakes can also use their crawling motion to twist and climb up trees and branches.
Additionally, a snake will use the scales on its abdomen to help it move ahead especially when crawling on a relatively smooth surface.
3. Crabs
Crabs are unique creatures because you’ll find that they swim swiftly in the sea and crawl equally fast on land.
Then again, certain species of crabs never go into the water and spend their entire lifetime on the ground whereas other crabs spend their entire lifecycle crawling on the seafloor.
Unlike snakes and alligators, crabs use their pincers and their legs to move on land.
Another thing that sets it apart from other creatures that crawl on the ground is the sheer speed with which a crab can move.
If you observe the movement of crabs on land, you’ll see that the creature uses two of its limbs on the opposite side of its body to propel itself forward.
But don’t be deceived by its unusual and clumsy movement. A crab is known for its speed, and you must have seen it scoot suddenly from one end of a beach to another in a matter of minutes.
Likewise, if a crab feels threatened and needs to run away from a predator, it can even crawl away at the speed of five feet in just a matter of a second.
The crustacean’s incredible ability to crawl on land makes it capable of creeping, running, and even moving sideways on all of its ten legs.
4. Seals
Seals are considered to be semi-aquatic animals, but they spend most of their life in water.
Seals are excellent swimmers, but when they emerge on land, their movement becomes undulating, and they seem to be using their heads to propel themselves forward.
Seals aren’t comfortable on the ground, and they aren’t good crawlers either.
Instead, you’ll find them lying in groups on the edge of a water body and only making the necessary movement on land if the need arises.
The primary reason is that seals don’t have any limbs to aid their movement on the ground.
They have flippers as forelimbs, but these are designed to help them swim in the water.
They use these flippers to move forward when on land, and their movement resembles that of caterpillars.
They’re also unable to rotate their flippers forward or backward to make the movement easier.
Hence, you’ll find that seals move on land with great difficulty, and they’ll try to combat this by wiggling forward.
They don’t typically turn around or try to move sideways because this will exhaust a sizeable amount of energy since it requires extensive maneuvering on their part, which they’re not used to.
5. Ants
Ants are unique creatures that belong to the insect family. You’ll find that ants can crawl on land, walls, backward, and forwards.
Many animals that crawl on land can’t make movements in all directions, but ants can.
If you check the movement of ants carefully, you’ll find that they have an alternating tripod system to move on land.
In this, the front and back leg of one side and the middle leg of the other side move together to take a step.
Then the entire setup is alternated to move another step. This unique system of movement helps ants move forward, turn around and even move backward.
Ants can crawl up and down a vertical wall in a similar manner. But they also use the hooks at the end of their tiny feet to adhere to the wall.
The entire setup of their limbs is designed to help them crawl swiftly on land.
Their legs are agile enough to hold up the weight of their body while allowing them to adhere to any surface they find themselves on.
6. Lizards
Lizards are reptiles that can crawl on any object they find themselves due to the help of the tiny hair at the end of their feet.
There are tiny hairs at the end of its fingers are called setae, and this hair increases the surface area of contact towards the spot on which they want to crawl.
The tiny hairs can increase the surface area by nearly forty percent resulting in the creation of Van der Waals force.
A lizard has four limbs, and if you look at its feet carefully, you’ll find five fingers on each of its feet.
Lizards tend to rotate their feet when they move, ensuring that the oppositely charged molecules are attracted to each other.
This will ensure that the lizard stays adhered to the surface and can quickly move ahead.
A lizard can detach its legs nearly fifteen times per second to keep the surface charged and help it progress.
These swift movements of the lizard’s feet and the generation of Van der Waals force allow lizards to easily crawl on land.
7. Octopus
It’s natural to associate octopuses with living in the sea and never venturing on land. However, a few of these aquatic creatures have been seen crawling on beaches.
The Abdopus aculeatus is an octopus that lives on land, specifically beaches.
Additionally, you might have seen a small octopus sometimes crawling from one tidal pool to another. This will be an algae octopus which is also known as the Abdopus aculeatus.
Octopuses use their arms when swimming in the water and these same arms are used to crawl on land.
Octopuses are nocturnal creatures, and they usually come out of their hideouts at night in search of food.
To move from one spot to another, you’ll find an octopus tightly gripping onto a rock while it propels itself forward with the remaining arms. They shorten and extend the length to move forward.
If you’ve seen videos of octopuses moving on ocean floors, you must have observed that their movement is similar to that of other mollusks.
However, they have more arms to help them coordinate their movement and with the help of these arms, an octopus can grip onto the ocean floor or on the land and propel itself forward.
