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!

Perhaps the Most Unpleasant But Interesting Facts About Cockroaches

It seems that there is no such person in the world who would love cockroaches. These disgusting insects often bother residents of apartments and houses, and besides, their neighborhood is not so easy to get rid of. What else is cockroaches infamous for? About this in the selection of cockroaches ...

The Actual Sizes of Some Things: 20 Examples With a Comparison!

The truth is, everything in this world is known in comparison! Human vision is an amazing thing, but alas, it is not always possible to trust it. Sometimes, in order to understand the real size of certain things, sometimes familiar to us, things, they just need to be placed next to those whose real sizes we know for sure. You will be surprised how big or small some objects, phenomena or creatures actually are, the real size of which we could not have guessed.