7 Most Dangerous Jellyfish in the Underwater World

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Portuguese boat (Physalia physalis)

The second name for jellyfish is physalia. Although this is rather not even a jellyfish, but a whole colony of polypoid and medusoid individuals. The «bite» of a Portuguese boat is extremely dangerous and painful (sensations are compared to hitting the skin with a whip). The main risk is the systemic effects of the poison. In severe cases, intense pain is followed by fever, shock, and impaired heart and lung function, which can lead to death. Physalias are accustomed to moving in groups of up to 100 colonies, and sometimes in resorts they have to close entire beaches because of them!

The Most Interesting Facts About Traffic Jams

Residents of megacities and big cities know firsthand what traffic jams are, especially at rush hour. This collection will tell you about the most fun and unusual facts regarding traffic jams that affect major cities in the world ...