Jellyfish are ancient creatures, they live on Earth for over 650 million years. These amazing animals came before dinosaurs and sharks. Some species of jellyfish can live in fresh water. Usually, except for the fact that these creatures sting, people know nothing about them.
The edges of the body of a jellyfish are the tentacles with cells containing a capsule of poison that causes burns. Tiny "harmonici" paralyze small prey. Jellyfish were watching fish and other sea creatures, people too often become victims of the toxin. But not all of these animals are poisonous. "Burning" is dominated by jellyfish in the Atlantic ocean off the coast of the United States.
They are mainly active in summer and autumn. Even Medusa, who was recently thrown on the shore, is a dangerous, yet its tentacles wet.
There are several types of jellyfish which are capable of its poison to kill a man, for example, sea wasp, which lives in the coastal waters of Australia. Every year this animal is dark gathers his "harvest" — from her touch killed about 60 people. Her toxin more potent than Cobra venom.