Shark Grin Postcard

This illustration is of a Shark Grinning. The shark linage can be traced back to before the dinosaurs. There are currently more than 440 species of sharks. Ranging from 7 inches in length to 40 feet. Most sharks live in salt water. There are a few that can live in either. The sharks teeth are not actually located in the jaw like humans, but, instead they are embedded in the gums. It is believed that sharks will have 30,000 teeth in their life time. This is because the teeth of sharks get replaced every 7-10 days. Their eyes are similar to humans, They are able to dilate their eyes, most marine animals do not have that ability. The importance of sight in sharks is debated. Sharks have another sense in addition to the 5 we are used to. Electroreception is the ability to detect e electromagnetic fields that organic material produces. In otherwords, they are able to sense where their prey is at by the aura that that species produces. But do not worry, although sharks get a bad name, they do not go after humans often. There are only 4 species of shark that have a tenancy to attack humans, great white, oceanic white tip, bull and tiger sharks. Even than, it is safe to film them without the aid of a cage.