Shark! For many, their size, power, and great, mouthwatering jaws fill us with fear and fascination. Not for me, I’m bewitched by them. Sharks kill only a few people each year, but media coverage and movie representation of attacks have marked sharks as voracious killing machines. Our fears—and appetites—fuel an industry that hunts more than 100 million sharks each year and threatens to purge these vital predators from the oceans.
The shark is an enchanting creature, over 400 different swim in the ocean today. Too many, sharks symbolize the terrible essence of ruthlessness, representing the ultimate savages of the seas. Although many folks would rather not deliberately socialize with these fearsome predators of the depths, I appreciate swimming among sharks. Sharks in addition to their direct predecessors are swimming within the world's oceans for well over three hundred million years, and were going about their business long before dinosaurs walked the world. The fact that sharks have survived thus far without changing very much is a long real tribute to the effectiveness of their anatomy.
Sharks are fishes, confined within the taxonomic class called Chondrichthyes (meaning "cartilage-fish"). Sharks besides other cartilaginous fishes (rays, skates, and rat fishes) differ from the skeletal fishes because sharks have a cartilaginous skeleton, and lack a swim bladder. Worldwide there are over six hundred different types of fish, not to mention three hundred species of sharks.
From time to time sharks are referred to as primitive creatures. They are a prehistoric group of animals, so assuming sharks are primitive is correct. Unfortunately, this assumption is wrong. Recent offshore studies have shown that sharks are, in fact, extremely educated. Most sharks have an incredible sense of smell. Sharks can become aware of a single drop of blood dissolved in as much as one million gallons of water. Numerous sharks can sense the minute electrical currents produced by the muscles of swimming fish. Certain sharks like the Nerf shark can feel at a great distance the tiny pressure variations generated by injured fish struggling to swim. Contrary to popular opinion, most sharks have exceptional low light vision, thanks to a mirror located behind the retina. This mirror allows light to reflect through the retina a second time. A shark may have many rows of teeth, for example, the great white shark has five razor sharp rows of teeth. When an old tooth breaks or becomes too dull, a new one rotates into place. Are these the attributes of a primitive animal?
Sharks come in many shapes and sizes. The largest fish in the ocean is, in fact, the marvelous whale shark, reaching about 60 feet in length. The smallest known shark is the pygmy ribbon tail cat shark, which is about six to seven inches long when fully grown. While many sharks like the Sand Tiger shark do have exposed teeth, they only eat small invertebrates. Other sharks have no teeth at all, feeding by...