Ocean
The ocean is a vast and wonderful place. It covers more of
the world thank land almost twice as much!
In fact, oceans cover 140 million square miles of the
earth’s surface. Seas are smaller than oceans and
are usually no more than 600 feet deep.
Dolphins are strong swimmers. Most ocean dolphins
can swim at speed of 15 miles per hour.
Dolphin
When dolphins want to find food they make
clicking or whistling noises. These noises
travel through the water and bounce
off objects like fish or squid.
They came from the first fish, which lived
500 million years ago! Swimmers can protect
themselves from shark attacks. Some divers
Shark
experimented with diving suts made of metal
to protect themselves from sharks.
But larger sharks can bite right through the metal.
