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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.