Tortoise Anatomy: What Tortoises Are Made of & Why

Tortoises are crazy cool animals, but a lot of people are confused about their anatomy and what goes on in that shell. Consider this your one-stop-shop for all questions on what makes a tortoise a tortoise. In this article we will talk about all the crazy and not so crazy things that may be on, or in, your wonderful pet tortoises.

The Tortoise Head

If you look at a tortoise’s head, they have a very distinct block-like shape and a beak. The tortoise usually has narrow-set eyes. Their noses are basically two little holes near the front of their beaks called nares. They use their nares to take in oxygen.

A tortoise has a long, wrinkly neck with five vertebrae, just like many other animals. Unlike most animals, however, tortoises can pull their head straight back into their shell. Imagine curving your neck backwards into a sharp S shape. That would hurt! But that’s totally normal for a tortoise.

Do Tortoises Have Teeth?

No. Instead of teeth to chew food, the tortoise uses a very strong beak, but it is not like a bird’s beak. With this beak the tortoise can shred and grind up foods. What they eat will vary depending on the species of tortoise and where they live.

Generally, a tortoise’s diet will consist of a variety of plants. Sulcata tortoises, for example, are originally from desert regions. They naturally feed on a variety of grasses, shrubs, and herbs, so their beak is perfectly shaped to handle those fibrous plants. Some tortoises have been seen eating prickly cacti!

Tortoises in captivity like to snack on whatever you feed them. As long as they can grind it up with that impressive beak and it provides the right nutrients, it’s okay to feed a variety of plants. Many tortoises enjoy a dandelion or two.

Do Tortoises Have Ears?

Many people think that tortoises don’t have ears at all. This is simply untrue. Their ears aren’t like ours, which has caused some controversy.

The ears on a tortoise are hidden under a scale behind the eyes and just above the jaw. It’s located near the back of the head. These scales or flaps cover an internal ear that goes right to the eardrum.

There is a big debate as to what a tortoise can hear, let alone whether they understand what they’re hearing. The argument goes that since tortoises, as far as we can tell, don’t communicate like a dog or bird, why do they have ears at all?

So far, however, there haven’t been many studies done to answer that question. For now, we’ll just continue to talk to our tortoises and hope they’re listening.

Tortoise Eyes

The eyes of a tortoise are relatively narrow-looking. It’s almost like they are squinting, though they do have decently sized eyes. A tortoise’s eyes are placed more forward, near their nose, as a tortoise doesn’t have that large of a head in comparison to its body. Their eyes are also placed at the side of their head, unlike humans’ forward-facing eyes.

To protect their eyes while burrowing, tortoises have a third eyelid. You can often just barely see this eyelid. But don’t be alarmed if you can’t see your pet tortoises third eyelid at all.

Unfortunately, there are not a lot of studies done on the subject of what a tortoise can see. Since we can’t ask them directly, we can only assume. It appears that they have rather decent vision, however. A tortoise can see in a small range of colors, which aids them in finding brightly colored fruits and flowers in the wild. To test this, you just need to hide a strawberry in their enclosure to see how long it takes them to spot it.

The Tortoise Body

A tortoise’s body is designed for life on land. With a heavy shell, elephant-like legs, and claws, they can live in some of the hottest and most inhospitable environments.

Do Tortoises Have Claws?

Yes, tortoises have claws! A tortoise walks on its toes like an elephant. This is called digitigrade. Tortoises have big claws which make them amazing diggers, some can even dig down ten feet!

The front legs are heavily armored with thick scales. Depending on the species, some scales can appear like spurs or spines which deter many predators.

Do Tortoises Have Webbed Feet?

No, tortoises don’t have webbed feet or flippers (it’s turtles that do!) Webbed feet are designed for swimming, and tortoises do not swim well. They are land creatures, so they have toes and claws.

Do Tortoises Have Tails?

Yes, all tortoises have tails. Often, for older tortoises, you can use the length of their tail to determine their sex. Males will often have a much longer tail than females.

Near the base of the tail is the cloaca, also called a vent. Both sexes will eliminate wastes from the cloaca. It is basically a multipurpose hole for the tortoise: poop, pee, and reproduction are all completed using the cloaca.

The Tortoise Shell

The tortoises shell is probably the most recognizable part of the tortoise. It serves as a very important tool for their survival. From portable home to tiny tank armor, the tortoise is ready for whatever comes its way.

What Are Tortoise Shells Made Of?

There are two major parts of the tortoise shell. The carapace is the top of the shell. The plastron is the bottom. The shell is made up of keratin, which is the same substance as your fingernails.

The Carapace

As the tortoise grows, its shell grows with it. As the shell grows, it creates those little circle-like shapes which are called scutes. These scutes will start out pale or almost white in color, but as the tortoise ages and the scutes grow they take on darker, more mature colors.

Each scute on the shell actually has its own name. The scutes on the outer bottom edge of the carapace and along the back end are called marginal scutes. The one at the back of the neck is the nuchal scute. The scutes along the sides are the costal scutes. And finally we have the vertebral scutes, which are directly down the middle along where the tortoise’s spine is.

The Plastron

The carapace is larger than the plastron, and both are connected by scutes called bridges. Starting near the neck of the plastron are the gulars, then the humeral scutes, pectoral scutes, abdominal scutes, femoral scutes, and then the anal scutes near the tail. Each of these scutes are in pairs.

For males, the plastron is slightly concave, allowing them to be able to mate with females. It’s like a weird puzzle. The female tortoise’s plastron is flatter since she doesn’t need to fit another tortoise beneath her. The anal scutes on female tortoises are shorter and more flexible, allowing her to lay eggs with ease.

Do Tortoises Have a Backbone?

Yes, but it’s hidden! Some people think that the tortoise’s shell can come off and wonder how they keep it from slipping. The shell of a tortoise is actually fused with their bones, primarily the bones of their spine and rib cage. Obviously, that would make it impossible for the shell to just slip off. Because the shell is fused with their bones, it can make it a little harder for the tortoise to breath if they are overfed and become obese.

Do Tortoises Have Scales?

A tortoise’s skin is usually quite wrinkled and dry-feeling. That can make it tough to tell if your tortoise is dehydrated. On that wrinkled skin are sections of hardened scales with a slight bumpy texture.

Most tortoises are in shades of brown and gray, but they can have some variations due to breeding in captivity. Color variations are called morphs, but the morphs for tortoises are limited. Color also depends on the species of tortoise that you are looking for and where they are naturally from in the wild.

Do Tortoises Have Hair?

No, tortoises do not have hair or fur of any kind. They are reptiles, so they have skin and scales.

It’s What’s On The Inside That Counts

A tortoise is an amazing animal, and that doesn’t stop on the scaly skin of these old creatures. The insides of a tortoise are quite unique. They don’t have anything extra, but it’s how their insides are arranged that is so interesting to us.

The tortoise has an interesting bladder as it can store liquids for longer periods of time in case the tortoise cannot find a reliable source in the wild. A lot of plant matter that tortoises eat contain water to some degree, and some tortoises have even been seen eating their own waste as a means of getting some liquid back in them. Luckily most tortoises don’t have to do this in captivity if cared for properly.

A tortoise, depending on the species, can actually live for a good while with no food or water. Sailors used to use this survival adaptation to their advantage, as terrible as this will sound. They’d catch a tortoise, flip it on its back, and keep it there as an emergency source of food while at sea.

Or that is how the tale goes, we would like to think that it’s just a wives’ tale. But it is true that a tortoise can store liquids in its bladder, which is why you shouldn’t try to scare them or make them defecate. In the wild they need those stores of nutrients in times of emergency.

Do Tortoises Have Lungs?

Yes. A tortoise’s lungs are held up in the top section of their shell. They have what is called chelonian lungs which are a lot like sponges. A tortoise breathes by forcing air in through the nares and into the lungs with a particular motion. It looks like they’re shrugging their shoulders, but they are just working their limbs to breathe.

These unique lungs are adapted so that if the tortoise finds itself submerged, it will be able to hold its breath for some time. Of course, a tortoise is not a turtle and most species of tortoise do not like being in water like turtles do. Some tortoises can’t even swim!

Can a Tortoise Smell?

Yes, and it’s a good sense of smell, too. To use their sense of smell, they pump their throat and move air past their Jacobson’s organ, which is an organ widely used by most reptile species. It can detect heavy, moisture-rich odor particles.

They can use their sense of smell to detect predators, find food, and decide if a spot of good for digging.

What Internal Organs Do Tortoises Have?

Just below the lungs up near the front of the tortoise and working our way down there is the stomach, liver, gall bladder, kidneys, and if the tortoise is male then the testes right by the kidneys. Under all these organs are the intestines taking up the center. Up higher in the chest of the tortoise sits the heart.

There are a lot more parts in a tortoise. Everything has an important function, but it’s much more than we intended to cover in this article. If you’re curious about all these other parts, check out this veterinary medicine site.

The Difference Between Tortoises and Turtles

What is the difference between a tortoise and a turtle? This is a common question that most people ask. Simply put, all turtles are tortoises, but not all tortoises are turtles.

This is a bit confusing and not very descriptive, but that’s why we are here. Here are a few quick tips on telling the differences between these two species.

• Turtles live mainly in and around water, spending little time on shore. Tortoises are only land dwellers and can’t swim well, if at all.
• Though turtles live primarily in the water, female turtles will come to land to lay their eggs and then return to the sea. The female tortoise may actually stay with her young until they are roughly 8 months old after hatching.
• Turtles often have a smoother shell than tortoises so they can slip through the water with ease. Tortoises have large rounded shells that are very heavy which are necessary for protection against land and aerial predators.
• Tortoises have stompy almost elephant-like legs and thick claws for digging. Turtles have slimmer legs and some even have flippers. If they don’t have flippers, turtles will have webbed feet used for swimming.
• Tortoises walk on their toes; this is called digitigrade. If they have feet instead of flippers, turtles will walk flat on their feet. This is called plantigrade.
• Tortoises are covered in thicker scales, especially along the outer edges of their legs, some will grow spur like scales which are useful to keep predators away. The scales of a turtle are smoother.
• Most Tortoises will have a more earthy or dusty coloration to them, this is to help in their camouflage on land, but these colors vary depending on species and breeding. Turtles tend to be more colorful and have a wider variation of colors.

Conclusion

Tortoises of all kinds have interesting bodies, both inside and out. And while we do not know everything about them yet, what we do know is they are an old and unique creature on this planet. They are one of the oldest reptiles on Earth, having remained largely unchanged since prehistoric times.

Related Questions

Can tortoises feel through their shell? Yes, they can. A tortoise’s shell is full of nerve endings and they can feel when you touch, pet, or rub their shell. Some tortoises even seem to enjoy the feeling.

Is a tortoise attached to its shell? Yes. The shell is fused with the tortoise’s spine and ribs. Please don’t try to make a tortoise come out of its shell as that can be extremely painful for the animal. Learn about it in this article called “Can tortoises and turtles live without their shell?”