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This shark is looking for its next meal.
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Sharks

For some reason, sharks have the reputation of being the "bad boy" of the sea. Movies such as Jaws give the impression that sharks are killing machines, eating everything in their sights. But only a few species of sharks are actually dangerous to humans.

The great white shark is probably the most famous of all the species. The great white can grow over 25 feet long! Fortunately, humans aren't the great white's favorite meal. Instead, they enjoy sea lions and other sea life. There are not very many great white sharks alive today.

A more common shark is the blue shark. It is much smaller in length and not as fierce as the great white. Blue sharks can be found all over the world, and are often seen near the surface.

The nurse shark is a lesser known species. It is very lazy, and is usually found on the ocean floor. The nurse shark grows to about 8 feet in length, and preys on shellfish. The horn shark is similar to the nurse. It is very timid, and doesn't grow longer than 4 feet. It hides under rocks during the day and comes out at night to feed on fish and crustaceans.

Finally, the largest shark and fish in the world is the giant whale shark. The whale shark can grow over 40 feet long! But don't let its size scare you. The whale shark only eats plankton, which are small organisms floating in the water.

So you see, sharks aren't all that scary! There are several more species, hundreds to be exact! Many are harmless creatures that are more scared of humans than we are of them!


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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA