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Why Do Land Turtles Hide In Their Shells?

By Kerry
Updated on

Turtles are known for their unique shell structure that allows them to move around from place to play without being detected by predators.

European pond turtle hiding

It also provides them with protection from threats and helps to protect their internal organs from becoming damaged by unwanted attacks.

The turtle shell is composed of two parts: the carapace (the top part) and the plastron (the bottom).

The carapace protects the animal from predators, while the plastron helps regulate body temperature.

Turtles have evolved over millions of years to become masters at hiding in plain sight.

Their shell structure has helped them survive for hundreds of thousands of years, but why do they do it?

In this article, we’re going to be taking a closer look. Read on to learn more!

Why Do Turtles Hide In Their Shells?

The most common reason that turtles hide in their shells is due to feeling scared of a potential threat, such as a dangerous predator.

In order to stay hidden, turtles need to be able to camouflage themselves against their surroundings.

This way, they can avoid detection by predators or prey.

This is where their shell comes into play.

When a turtle feels afraid or as though they need to protect themselves, they will extend their neck out of their shell, which causes them to expand outward.

This expansion creates an outline shape on the outside of the shell, making it look like a larger version of itself. This makes it harder for predators to see the actual turtle inside the shell.

A turtle’s shell is made up of two parts – the carapace and plastron. These two parts help protect the turtle from predators and provide a place for it to rest.

The carapace is made up of several different layers. It serves as protection for the turtle and provides a surface on which the turtle rests.

The plastron is located underneath the carapace. It holds the air sacs that allow the turtle to breathe.

In addition, the plastron acts as a stabilizer when the turtle moves.

What Is The Scientific Reason That Turtles Hide In Their Shells?

Scientists believe that the main purpose of the turtle shell is to help regulate the internal temperature of the animal.

A turtle is hiding in its shell

The shell acts as insulation, protecting the animal’s vital organs from extreme temperatures.

In addition, scientists believe that the shell gives the turtle a better grip when swimming. It also provides more protection from predators.

How Does A Turtle’s Shell Work?

A turtle’s shell is made of calcium carbonate, which is what makes up seashells. When the turtle breathes, it pushes out oxygen through its lungs and takes in carbon dioxide through its gills.

When the turtle exhales, it pulls in carbon dioxide through its trachea and pushes out oxygen through its skin.

Because the shell is porous, the oxygen passes right through the shell and into the bloodstream. Carbon dioxide, however, cannot pass through the shell, so it collects inside the shell.

As more carbon dioxide builds up, the turtle begins to feel uncomfortable.

Its brain sends signals to the respiratory system telling it to take in more oxygen. As a result, the turtle starts breathing faster and taking in more oxygen.

As more carbon dioxide builds up in the shell, the turtle becomes increasingly uncomfortable.

Its brain sends another signal to the respiratory system telling the turtle to slow down. As a result, it slows down and takes in less oxygen.

Eventually, the turtle feels completely comfortable again. At this point, the turtle stops breathing.

Because there is no longer any carbon dioxide building up in the shell, it will stop absorbing oxygen.

What Type Of Turtles Hide In Their Shells?

Even though it is a well-known fact that turtles often hide in their shells in order to rest or if they feel fearful and want to hide from a threat – it is not so well-known that there are certain types of turtles that display this behavior more frequently than other types.

More so, even though all turtles have their own shell, not all types of turtles will completely nestle their neck and limbs inside but will instead opt to conceal themselves only partially.

The main type of turtle that is unable to retract entirely into their shells are sea turtles.

Close up head of turtle hiding on wood

For the most part, almost all turtles and tortoises will decide to conceal their whole body in their shells whenever they feel threatened.

Once they have done this, this will then sadly mean that their entire body is hidden, and only the outer shell will be visible. To a predator, this shell will look like a rock.

In addition to this, even if a predator knew that the turtle was inside, the majority of predators are far too large to be able to get inside them.

The most common types of turtles that conceal themselves inside their shells are as follows:

Tortoises (Gopherus Agassizii)

This species of tortoise can be found throughout North America. They are known for being very docile and easy to care for.

However, they also tend to be rather shy and will normally retreat into their shells at the first sign of danger.

Terrapins (Geochelone Pardalis)

This type of turtle is native to Australia. They are much smaller than most other turtles and are usually seen swimming around in shallow water.

They are extremely active and quite playful. Even though they swim in the water, they typically reside on the land.

Chelonia Turtles (Chelonia Mydas)

These are one of the most popular types of turtles and are commonly kept as pets. They come in many different colors and sizes and are considered to be omnivorous.

They are also known for being very friendly and curious animals.

Snapping turtles (Chelydra Serpentina)

This type of turtle comes from the family Chelydridae. It has been reported that these turtles are capable of producing a loud snapping sound when threatened.

Loggerhead turtles (Caretta Caretta)

This type of turtle belongs to the family of Cottidae. They are mostly found along the Atlantic coastlines of North America. They are generally considered to be peaceful creatures.

Why Can’t Sea Turtles Hide In Their Shells?

Sea turtles are unique because they cannot fully conceal themselves within their shells. This is due to the fact that they have flippers to swim with instead of legs.

Turtle swimming in the sea

In addition to this, sea turtles also typically tend to have smaller shells than land turtles and tortoises, which makes it physically impossible for them to be able to conceal themselves.

How Did Turtles Evolve Their Shell Structure?

Turtle shells were originally made up of hardened skin, but evolution eventually led to the development of the hard outer layer of bones that we know today.

The first step was the development of the carapace, which covered the head, back, sides, and tail of the turtle. Next came the plastron, which protected the underside of the turtle.

Finally, the last major change was the formation of the ribs, which allowed the turtle to breathe.

When Did Turtles Begin Using Their Shells As Homes?

It wasn’t until about 100 million years ago that turtles began living in their shells.

Prior to this point, turtles lived in the ocean, where they could swim freely.

However, as the continents began moving closer together, there became less space for sea life. As a result, many species of marine reptiles started living on land.

One of these species was the modern-day turtle. These animals adapted to living on land by developing a new lifestyle.

Instead of just relying on their fins to propel themselves through the water, they now used their legs to walk along the ground. As a result, they needed a new place to live.

They found one in the form of a protective shell.

How Long Does It Take For A Baby Turtle To Develop Its Shell?

Baby turtles are born with soft, flexible shells. As they grow older, however, they start to use their shells to protect themselves.

A baby turtle’s shell starts off as a thin membrane covering the top of its body.

Over time, the membrane thickens and becomes stronger.

Eventually, the turtle reaches adulthood and develops a fully formed shell. This process takes anywhere between four months to two years.

Final Thoughts

There we have it.

Now that you have taken the time to read through this guide, we’re hoping that you now have a much better understanding of the reason turtles and tortoises often conceal themselves inside their shells.

For the most part, turtles will typically do this in order to hide from a predator, although sometimes it can simply be down to them wanting to rest.

Don’t forget – sea turtles can’t do this due to their unique anatomy.

We hope that this information has provided you with what you were looking for.

Thanks for reading!

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About the author


Kerry White is an avid dog lover and writer, knowing all there is to know about our furry friends. Kerry has been writing for PetDT for three years now, wanting to use her knowledge for good and share everything she can with new dog owners.Kerry has two dogs herself - a German shepherd called Banjo and a chocolate labrador called Buttons. Kerry knows more than anyone how adjusting to new life with a puppy can turn your life upside down, and she wants to ease some of the burdens through her articles.