A few facts about sharks
he oldest sharks there are over 400 million years, sharks are older than dinosaurs.
There are about 350 species of sharks; their size can vary from 15 centimeters to 18 meters.
It should be noted that interesting fact. what is the ratio of brain to body weight of sharks, almost the same as in mammals, from which the conclusion that sharks are as smart as other animals
Life expectancy of sharks for about 30 years. But the sharks are long-lived. So, the life expectancy of the whale shark exceeds 100 years!
The average rate of movement of sharks about 8 km/h, but during the attack the shark can accelerate up to 19 km/h for Example — the Shark-the Mako and the great White shark can accelerate to a speed of 50 km/h.
The shark is able to feel one gram of blood dissolved in 600 thousand liters of water, at a distance of 500 meters.
Biologists noted the fact. that person mostly attack: tiger shark, hammerhead shark, Mako shark, bioplanta shark, bull shark, the sand shark. blue shark, and sea Fox. Almost half of all shark attacks on humans over the death of a person .
As a result of shark attacks every year in the world affecting up to 300 people. Today in most tourist countries prefer not to release information about shark attacks on tourists. For example, locals — only area of the resort of Eilat, as a result of shark attacks killed 2-3 people per year. Basically it is the tourists bathing the yacht in the open sea.
The shark begins to consider the victim around five meters. From a distance she the victim only feels and hears.
Attacking the shark first plunges into the victim’s body, the teeth of the lower jaw. The upper teeth as the knife cut him, inflicting terrible wounds.
In the stomachs of sharks found a variety of subjects — for example, bottles, jute bags, postal parcels, shells and grenades, spinning rods and even a large African Tam-Tam. In 1952 Italian fishermen said about the sad message delivered by a shark. In the stomach they’ve caught the shark was the bottle and in the bottle — a letter to a French fisherman, who, dying alone in the sea, sent his wife and children farewell.
Almost all calves are born with a full set of teeth and is able immediately to protect themselves and to find food.
New teeth of sharks appear every 8 days.
Depending on the form of sharks, their jaws may be from 30 to 400 teeth arranged in several rows.
The compression force of the jaws, a four-meter shark — 20 KN.
A three-metre shark at one time to swallow a whole beef side.
A week shark is enough food in only a 3% – 14% of its own weight.
Not all sharks are predators. Many feed on plankton, jellyfish, small fish, like the giant whale shark.