Sharks

Sharks are the most skillful under water predators.

Most shark detect prey with their finely turned senses, then charge suddenly at great speed biting with bone crunching power.

There are so many different types of sharks a few venture into the mouth of rivers.

They live in seas and oceans,some staying in coastal shallows others in deeper water.

Lifespan:up to 70 years

Habitat:seas and ocean

Number of family's:35

Number of species:

513

One of the reasons that sharks are such successful predators is that they have such super senses.

Two-thirds of a shark's brain is dedicated to its keenest sense -- smell.

Some sharks have eyes similar to a cat.  A mirror-like layer in their eyes allows them to see better in the water.  This allows the shark to hunt in clear seas or murky water.

To top it off, sharks have a few unusual senses.  For instance, they are able to feel vibrations in the water using a line of canals that go from its head to its tail.  Called a "lateral line", these canals are filled with water and contain sensory cells with hairs growing out of them.  These hairs move when the water vibrates and alerts the shark to potential prey.

Sharks also have a sensory organ called the "ampullae of Lorenzini" which they use to "feel" the electrical field coming from its prey.Sharks have the most powerful jaws on the planet.  Unlike most animals' jaws, both the sharks' upper and lower jaws move.

A shark bites with it's lower jaw first and then its upper.  It tosses its head back and forth to tear loose a piece of meat which it swallows whole.

Each type of shark has a different shaped tooth depending on their diet (the shark in the photo is a great white -- you can tell he's a carnivore just by looking at those sharp, pointy teeth!).  

A shark may grow and use over 20,000 teeth in its lifetime.In some form, sharks have been around for about 400 million years.  They are the top predators of the ocean's natural food chain.

Even before dinosaurs roamed the earth, sharks hunted through the oceans!  They're such good survivors that they've had little need to evolve in the last 150 million years.

There are over 400 types of sharks -- at least 30 of these species have been known to attack humans.  They range in size from 6 inches to 45 feet. 

These ancient predators fascinate adults and children alike.

Scientific Information:  Sharks belong to the class of fish, Chondrichthyes.