How Many Bones Do Sharks Have In Their Bodies?
Sharks are famous for a lot of things. There are the pop culture references, the fear they create of going in the ocean, and also the ‘fact’ that they can never stop swimming. However, another super popular question people ask about sharks is: how many bones do sharks have in their bodies?
The short answer, which may surprise you, is none. Yes, it’s true. These majestic and powerful beasts that thrash on huge prey and swim non-stop through the depths of the ocean have no bones.
What Are “Bones” Anyways?
Here’s where the technicality comes in. The bones that make up the human skeleton are there to provide our bodies with shape, rigidity, and strength, as well as protection of our organs. They basically provide us with a framework to connect muscle and tissue.
The skeleton of a shark, however, is made up of cartilage, not bones. Bones are hard, inelastic, and tough parts of the vertebral skeleton. Cartilage is soft, elastic, and flexible. In a human, cartilage protects bones from rubbing against each other. But in a shark, cartilage forms the structure of its body, and also provides it with strength.
No Bones, Eh? But What About…
So how many bones do sharks have in their bodies? Now that we know the answer is ‘none’, let’s explore why.
The cartilaginous skeletal structure of a shark is lighter and aids in floatation. Because of this, a shark has speed and power, but without all the weight. In fact, sharks have a thicker skin on them to make up for their lack of protection from bones.
Do Sharks Have A Back Bone?
Sharks have vertebrae, and are indeed classified as vertebrates because they have a spinal column. However, nothing about the definition of a spine says that it needs to be made of bone.
The primary role of the vertebrae in general is to protect the spinal cord. Because the spinal column of a shark is made of cartilage, it’s super flexible. This is crucial to the shark’s mobility and ability to move through the water they way they do.
They Must Have A Skull Though…
Sharks do have a skull, but the question ‘how many bones do sharks have in their bodies’ also applies to the skull. It’s made of cartilage, which also allows their jaws to be more flexible and extendable.
If a shark had a rigid jawbone, it would not be able to open its mouth so wide to eat its prey. Plus, the relative flexibility of the cartilaginous skull allows the downward force of their bite to be faster and more powerful!
Are Shark Teeth Bones?
If you’re wondering: how many bones do sharks have in their bodies, you’d think that their teeth might be an exception. However, this is not the case.
Just like humans, shark teeth are made of dentin, a calcified tissue. In fact, dentin is stronger and denser than bone, and it also fossilizes well. That’s why sharks have that deadly bite, and why they’re some of the most deadly predators on the planet!
Related: These scary ocean pictures go way beyond just sharks.