Shark Anatomy

Shark Anatomy

There are more than 300 shark species in the ocean, but they all have the same basic anatomy.

This amazing anatomy masterfully designed by evolution is what sets sharks apart from other types of aquatic life including whales and dolphins.

Understanding the basic description of shark anatomy will help you to understand the incredible evolutive adaptations that have made sharks flawless predators.

There are six important anatomic structures characteristic of sharks that will be described below in greater detail.

The Amazing Shark Anatomy

Cartilage instead of Bones

All sharks have cartilage for their skeleton rather than bones. This is very different from humans and most types of land animals. Having this cartilage though is what allows them to move at unbelievable speeds through the water.

Dermal Denticles

Since sharks don’t have bones they rely on dermal denticles on their skin to help them keep the right shape. 

Shark skin is very rough because if you see it very closely it is covered with small denticles.

Denticles are found all over the body of every species of shark out there. They help make it easier to swim and help the shark to save energy. They also help to protect the shark skin from various elements in the water.


Jaw & Teeth

Sharks don’t have a jaw that is attached to their skull. Instead it moves as separate piece. The upper and the lower jaw can work on their own without the other moving. This allows the shark to have a very powerful pull and to be able to latch onto what it wants fiercely.

Sharks have many rows of teeth, which reach up to 15 rows of teeth for the biggest toothed sharks.

Shark teeth are extremely sharp as most sharks are meat eaters. They can rip through meat and bones instantly without any struggle at all. Sharks loose their teeth all the time and one from the rows behind it will move into that position so they are always geared with a full army of them to attack. They can lose their front rows of teeth every couple of weeks to a month. It is estimated a shark will go through 20,000 teeth in its lifetime.

Liver

Just like humans and many other types of animals sharks have a liver. They use theirs differently though. They are able to store oils in it for a very long time. The more oil they store the less often they have to eat.

Sharks are able to thrive on the oil that has been reserved in their livers for weeks, months, or even a year before they have to feed again. Once the level of oil in the liver gets low though the hunt is on. A shark never wants to deplete what is stored in the liver.

Tail

Each species of shark has a unique tail design. This has to do with the overall size of the shark as well as what the purpose of the tail is. In many instances the tail allows the shark to move very fast in the water. Other times it is to help balance the movements of the shark so that they can glide along gracefully.

Tails give them the ability to make flexible movements, so make the best use of their cartilage skeleton.

See the tail chart...

Fins

All species of sharks have fins as well. They have two sets of them that are matching pairs. They help them to move along in the water as well as to pick up vibrations that are taking place. There is a dorsal fin on the back, sometimes two of them depending on the species, that helps with balancing. The anal fin on the underside of the shark serves the same purpose.

It is often said that the anatomy of an airplane is very similar to that of a shark. When you visualize this in your mind you can see it is very true. There is a tail and the wings to help balance everything and to give it speed. While there is no proof that the dynamic design of an airplane was developed from the shark it does make sense. After all they have been able to thrive with that body design for millions of years. 

Highly Developed Senses

The highly developed shark senses are among the most important anatomic structures of the shark.

Shark senses are only listed below, but detailed information is included in our page Shark Senses