Scientific name : Carcharodon Carcharias

Meaning : 'Jagged Teeth'

Common Names : Great White, White Shark, White Death

Family : Lamnidae

Diet : Seal, sea lion, whale carcass, dolphine, penguins, fish (including other sharks) and any thing they can get

Location : Sea with temperature between 12 and 24C ( the most popular place is South Africa, California, Mexico and Australia )

Period : Quaternary, Holocene ( modern period )

Length : 4 to 5.2m ( Some specimens believe to be exceeded 6 meter or even specimen over 10 meter length are claimed to be found )

Weight : 2240- 3200kg

 
Introduction

The Myth of Infamous Man-eating Shark

  Great white, the shark which gained its brutal imagine by Steven Spielburg's movie 'jaws', have long been the nightmare of many people as 'man-eating machine'. However, this illusion is surely wrong because great white will generally not prey on human. The reason of most white shark attack reports is misrecognising human, especially surfer, as their prey, seals and sea lion. In this case, white shark usually reject to eat human once they found that they made a mistake. Another reason for the shark to bite human is the 'testing-bite'. Great white, like human, is a curious creature for many things, alive or not, in the ocean. In contrast to human, they study new things not by hands as we do but by teeth. In some extreme cases, the curiousity of whites are even painful as well as fatal. Despite these, the white sharks are generally not interested in attack man and they killed much lesser people as we thought. Actually, the bees and wasp kill more people then the white sharks do.

Appearance

   Great white, like other sharks, have sharp sense of olfactory as well as ampullae of Lorenizi. According to studies, the shark can feel blood in one faction per million sea water. This means, the shark can smell injuried animal a few kilometers away and it can increase the chance for them to find am injuried prey.

  Another feature enhancing sharks to find a injuried animal is the ampullae of Lorenzini. Ampullae of Lorennzini is a modified lateral line of sharks which allows them to detect things like eletricity or even magnetic fields. When an animal swimming or struggling in the sea, there is usually some volt produced to the sea. The lateral line of fish is efficiently to detect such volts and find their preys or enemies. The modified lateral line in ampullae of Lorenzini are even sharper than any lateral line to since such volt. With the structure, the sharks can find injuried animals in the sea by plotting the specific volt cause by struggling. And hence killed the animals with less efforts. Some scientist even think that the ampullae of Lorenzini allow some sharks to detect magnetic field of the earth which work as a compass in the shark's bosy. This can guide the way of the sharks.

  However, on the other hand, ampullae of Lorenzini is also the weakness of any sharks. Traditional way to cope with shark attacks is hitting sharks' nose. The reason for beating the sharks' nose is that the sharks' nose have dense ampullae of Lorenzini on the surface. Once the sharks' nose are being hit, the structure will be over-sensed. Thus, the shark may got stunned and go away.

Behaviour

  The main preys of white sharks are varies depending on location. But most of the preys like seals, sea lions, penguins and tunas are good swimmers. That's why, it is hard for the white sharks to catch their prey by simply chasing the animals. As a result, they developped a new way to change the preys.

  The belly of the sharks are white in colour and the dorsal colour of the sharks are grey and darker. This allow the shark hide in the open sea when the colour of its back completely suit the sea buttim and the colour of its belly completely suit the sea surface. And when a prey is approaching, the white sharks swim to the preys' side quietly and quickly. And before the preys' realize, the white shark make a sudden attack from the buttom and kill the preys with no time. It is not uncommon to see a white shark jumpping from the sea surface to kill their victims. The triangular and knife-like teeth are big and sharp enough for tearing their prey apart, needless to say to kill. Sometimes when the sharks handling the tough preys, their teeth may tore apart from their jaws. In this case, like some reptile, their teeth will go again from the jaw. An average shark may grow thousands of teeth during their life time.

Enemies

  Notwithstanding the white sharks are apex predator in the ocean, they still do have some enemies. Orcas (killer whales) are recorded as a predator of shark. In a case, a adult female whale killed a shark for eating its liver. And there is a species of puffer fish mainly prey for sharks. They let themself be eaten by sharks and swim to thier stomach. After sometimes, they start to blow up themselves and use their spine to break though the sharks stomach. And after a whiel, they can eat the shark alive in the sharks' belly.

  And of course, the greatest enemies of great white is human. Human recently continously devastating to the shark's habitat and complete for their prey like tuna. And what's more? The fishing industry even carrying a massacre to the shark for their fins. After a few decades, the sharks may vanish from the earth because of our philia of shark fin soups. At the end, I would like all of you having a facebook to join and invite your friends to join the group called the 'Pangaea shark's project'. Hopefully this will raise all of your attention to stop the sharks from extinction!

http://www.facebook.com/home.php?#/group.php?gid=248020642907&ref=ts