The Dead Sea is around 8.6 times more salty than a ocean. This salinity makes for a harsh environment where animals cannot flourish, because they cannot drink it, hence its name.
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It is called dead because it is thought to be without life by most people.
There is however some algae that actually thrive in this water. They are specially adapted and to my knowledge are not found elsewhere in the world.
There may also be bacteria called halophilis, an archeabactera that can survive in extreme conditions.
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Metaphorically, the Dead Sea is called that because water does not flow out of it. All rivers lead in, none go out--as if the river dies in it.
There is a thriving tourist industry as people visit the lowest place on earth, float on the water and take the salt and mud baths.
Also there is chemical industry that extracts the salt and potash and sells it around the world.
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It is called the dead sea because no living thing can live in it. The amount of salt would cause any living thing to die as all its water will travel into the surrounding water. To understand why read up on diffusion and osmosis. However some very few types of bacteria can survive there, because they can handle extreme conditions.
