What is a Shark?
Sharks are a type of fish 3 to 4 hundred of theses are sharks. There are different kinds, and species of sharks. Most live in seas, and some live in rivers or lakes.
Taking Shape
Many sharks are gray, with a long, torpedo-shaped bodes. There are lots of sharks that have different shapes and sizes. For example, hammerheads have distinctive, or they might have a flattened head, and numbers or sharks live on the seabed and have a flat bodies.
Size Matters
Sharks have a reputation of being huge or tiny, and ferocious killers. But some fewer than a fifth of them are larger than humans. An average , a shark can be up to 60-90 cm long (2-3 feet). The largest shark, is the whale shark, is longer than a bus, while one of the smallest is the spined pugmy shark, is about the size of a banana.
Are Sharks Dangerous
Although about thirty species of sharks have attacked humans, only a few are thought to have killed them. Sharks attacks are very rare and most don't cause serious injuries. Sharks such as the basking shark are bug enough to hurt or kill humans, but they are harmless.
Where Do Sharks Live?
Sharks live in different parts all over the world. From warm tropical seas to cold polar waters. Some live deep down in the bottom of the sea, while others live on surface. Many sharks live on coral reefs. these rock-like structures are found in warm, shallow, clear water of tiny animals called coral polyps.
Not Like Other Fish
Most fish, like people, have skeletons made from bones. All sharks have skeletons made of a lightweight flexible material are called cartilage.