All turtle species and tortoises are distinguishable because of their shell covering. The shell is there to protect the turtle and serve as a home. Now, you may wonder if shells are developed as baby turtles grow. Or are turtles born with shells already?
The answer is that they are born with a shell in their body. Turtle shells are part of a turtle’s exoskeleton. And just like any other bone in our human body, turtle shells also grow as the turtle matures into adulthood.
This article will discuss what you need to know about turtle shells and their importance as part of the body.
Are Turtles Born With Shells?
Are turtles born with shells? This question baffles both adults and kids alike. Understanding the current biology of turtles will help us take care of them as pets.
Turtle shells do not just appear out of nowhere. Hatchlings are born with their shells covering their bodies. However, a baby turtle comes into the world from an egg with a soft shell. Eventually, as the young turtle grows, its shell hardens to ward off predators.
Aside from protection, turtle shells also serve as water, fat and waste storage. It is where a turtle keeps its much-needed nutrients and minerals, such as calcium. Turtles use calcium to strengthen their shell and bones and assist in muscle function. Without minerals like calcium, a turtle won’t attain an optimal level of wellness.
Before, scientists thought that evolved turtle shells were mainly for protection. But, shells also served purposes for burrowing, swimming, buoyancy, heat absorption, and smoother movements.
Parts of a Turtle Shell
A turtle shell is composed mainly of two parts: the carapace and the plastron.
The carapace is visible to the eye since it is the top of the shell that we always see when the turtle is upright.
Conversely, the plastron is the bottom shell that protects the turtle’s lower body. It is also considered the turtle’s belly.
Scutes, the hard scales covering the shells, give the turtle a layer of protection from predators and other external factors that may harm it. A scute is extremely hard, so if predators attempt to bite it, they cannot penetrate the turtle shell.
Developmental Stages of a Turtle Shell
The development of a turtle shell starts when a mother lays turtle eggs. The embryonic development begins with notochord and somites, which lead to spine formation. The shell growth starts 20 to 30 days after embryo formation.
At the start, the shell will look like a simple protuberance. However, as soon as the carapacial ridge forms, it will become more like a turtle. From there, the carapace starts to grow along with bone formation.
While the carapace develops, the plastron starts to form. This is also the time when ribs and vertebrae begin their development. The ribs grow in the carapace and connect to the vertebrae. The spinal column also fuses with the carapace.
The last stage is the development of scales covering the carapace and plastron.
Older and adult turtles may shed off thin layers of their shell. The peeling and shedding process of the shell is perfectly normal for most turtles. But, if the shedding happens in a young turtle, a non-shedding species or a tortoise, then it is alarming.
The frequency of peeling and shedding depends on the turtle’s age and species. Common aquatic turtles that shed include, but are not limited to, diamondback terrapins, map turtles, painted turtles, yellow belly sliders and red-eared sliders. Again, it is important to note that baby sea turtles should not experience shedding since it normally occurs in older turtles.
How Do Turtle Shells Differ From One Species to Another?
The shell has a similar structure, but it may differ in shape and color as each turtle adapts to their own habitat. For example, a sea turtle has to adapt to water as opposed to a land turtle.
Some aquatic turtles, such as softshell turtles, a species of freshwater turtles, do not have scutes. Instead, a softshell turtle’s carapace has small spines and is flexible. Female turtles from this species have a carapace that measures 7 to 9 inches, while males have 5 to 10 inches. Another sea turtle that does not have scutes is a leatherback sea turtle.
Now, you may wonder why most sea turtles do not have a very solid shell with a strong carapace and plastron. That is mainly because sea turtles tend to dive deep into the water rather than conceal themselves in their shells.
However, there are also sea turtles with scutes, such as the green sea turtle. This species has 5 central scutes and 4 lateral scutes. Most sea turtles use their shells as storage for minerals and nutrients they need to live underwater.
Will a Turtle Die Without Its Shell?
Questioning whether a turtle can die without its shell is like asking if a human can live without skin. That said, the answer is no. A turtle’s shell is essential for its survival. While parts of the shell may get chipped or damaged at some point in a turtle’s life, total removal will cause the turtle’s demise.
Aside from protection, storage and shelter, the shell also consists of bones and nerve endings. It also protects the turtle’s vital organs and is connected to its rib cage and spinal cord. These are crucial parts of a turtle’s whole body system. That is why the carapace and plastron should never be removed.
Shell Injuries: What to Do?
Fret not if a part of the shell has been broken. A broken shell does not necessarily result in death. If there is an injury of some sort, treating it is necessary, as with any other animal injury.
A broken shell isn’t uncommon for pet turtles. They are also common for turtles in the wild, especially when accidentally stepped on. A shell injury can be classified into two types:
A depression fracture happens when there is a break along the middle of the carapace that may result in a damaged spinal column. This fracture may heal naturally since the shell comprises living and natural materials. Thus, healing itself.
For mild to severe fractures, however, consulting a vet is recommended.
Missing Shell Fragments
Broken and missing shell fragments may be more fatal than a fracture. When a shell fragment is missing, it may lead to exposure to harmful pathogens that can enter the turtle’s fragile system. So, bringing the turtle to a vet is of utmost importance for treatment.
Tests and assessments will be done so that proper treatment can be given.
Also, if possible, ensure that turtle shell damage is prevented in the first place. You can provide a proper living space, such as a clean tank and the right diet full of nutrients and minerals needed for a stronger shell.
Identifying Turtle Species Through Their Shell
The painted turtle is the most common native turtle in North America. It has 4 different species: midland painted turtle, southern painted turtle, eastern painted turtle, and western painted turtle. All of these species have olive to black carapace and red or dark orange markings on the enlarged scutes. You can also further distinguish them through the presence of red and yellow stripes around their head and neck.
This is one of the species that does not shed parts of their shells. A wood turtle’s carapace has scutes with irregular pyramid shapes lending it its distinctive sculpted appearance. The carapace has differing amounts of yellow, black and brown patterns or lines, while the yellowish plastron has a big dark botch on the outside corner of each scute.
Box turtles have a terrestrial habitat similar to a tortoise. It has more than seven species, including the eastern box turtle, spotted box turtle, and three-toed box turtle. A box turtle is highly recognizable for its domed carapace and hinged plastron. This is beneficial for protecting itself from predators since it easily allows the box turtle to retract its head and legs.
The carapace of an adult and sub-adult loggerhead turtle is reddish-brown and slightly heart-shaped. The plastron has a pale yellowish color. Meanwhile, hatchlings of this species have dark brown carapace and yellow to tan plastron.
This semi-aquatic turtle is Ontario’s smallest turtle consisting of a shell only 13 cm long (or less). It has a smooth black shell and is recognized with its bright yellow-orange spots splattered all over the carapace.
A snapping turtle has a carapace length that may be as long as its tail. The shell typically ranges from 8 to 8.5 inches and may be dark brown, tan or black in color.