Perfect sense of smell and good eyesight, plus the ability to sense the electric fields of the animals assigned the king of the seas. With this sense, a shark can detect the smell of prey blood, or urine, for miles away. Therefore, many people think that if they bleed, they should not swim or surf because they were afraid of being attacked. But it is due to the shark’s good sense of smell that it easily distinguishes human blood from wild prey, so it cannot be confused and will not attack because sharks do not consider humans as prey. Most attacks are caused by sharks mistaking the surfers or swimmers at sea for seals or sea cows.
The shark’s eye is similar to that of other vertebrates, including the cornea, retina, and lenses. Their eyes adapt to the marine environment by being covered with a thin film. This curtain is behind the retina and reflects light to the retina, increasing clarity in the dark. The effects of this curtain are varied, with some types of sharks helping them adapt to the dark more easily. Sharks have eyelids but do not blink because the surrounding water cleans their eyes. Eye protection are the eye membranes. This membrane covers the eyes when they eat or be attacked. Some sharks, including the white shark, do not have this membrane, but they roll their eyes when attacking prey
See more at: Shark nice butt poster