Sharks

Alistair EllulJunior 3A

What are sharks?

• Sharks are amazing fish that have been around for about 400 million years. The first sharks existed before the dinosaurs existed.

• Sharks have no bones. They have a skeleton made of cartilage. Cartilage is a strong substance but is more soft than bone. Our nose and ears are made of cartilage. So, sharks belong to the group of fish called cartilaginous fish.

Where do sharks live?• They live in waters all over

the world, in every ocean, in some beaches and even in some rivers and lakes. 

• Some sharks live near the surface of the sea, some live deep in the water, and others live on or near the ocean floor.

• Some sharks live in warm waters, for example hammerhead sharks

and tiger sharks.

• Other sharks, such as blue shark, live in

temperate water which is neither hot nor cold.

• Others, like the dogfish live in cool waters.

What are the shapes of sharks?• Sharks have different body shapes.

Most sharks look like this:

• Some sharks have a flat body. This is an angel shark:

• The whale shark has spots and stripes and looks like a whale.

How do sharks eat?

• Sharks have a lot of teeth. They may have up to 3 000 teeth. Most sharks do not chew their food, but gulp it down whole it in large pieces. The teeth are arranged in rows. Most sharks have about 5 rows of teeth.

What do sharks eat?• Almost all sharks are carnivores that is they

eat animals.

• Some like the tiger shark eat fish, other sharks, and marine mammals.

• Some like the  angel shark eat shellfish like crabs and clams.

• Others like the whale shark are filter feeders and eat a lot of plankton and small animals.

How do sharks have their young?• Some sharks are oviparous. These sharks

lay eggs and the eggs hatch in the sea.

• Some sharks are viviparous and give birth to live young.

• Most sharks are ovoviviparous that is the eggs grow and hatch inside the mother’s body and then they are born.

Sharks that I saw at the National Aquarium

Shark eggs Manta ray

Black tip reef shark