Hippos are definitely one of the most dangerous, ironically herbivorous animals. Not sink in water - the fat keeps them afloat, they can even take a nap while floating on the surface. The bullets ricocheting from their teeth - they are so strong... But their 4-cm skin, which the doctor has to sew up with the metal wire if necessary, - bullets shoot through. And hippos, like nearly everything in the wild today - an endangered species.