A Look At Fascinating Sharks
View PDF | Print View | Html View
Written by: Andries Joubert
Total views: 10 |
Word Count: 446 |
Date: Wed, 3 Feb 2010 |
0 comments
Many people have a narrow idea of what sharks are and their relevance on the planet. Most equate sharks with a movie in which a Great White is cruising beaches for unsuspecting bathers in the middle of the night. This is a very unfair depiction of one of the most majestic creatures on the planet.
These fish have been in existence longer than almost any other creature on earth. They have evolved to survive a multitude of changes that have taken place on the planet over the last four hundred million years. There are some characteristics they share and make them stunning to study and watch.
The entire body of a shark is designed for forward motion. Many of the species never sleep, but must continually move in order to get the oxygen that they need to survive. In addition, their dorsal fin prevents backward movement. The tail fin on each fish is specifically designed for it's primary purpose. The Thrasher shark uses it's tail fin to corral other fish, the Tiger gets maximum power for cruising slowly and for sudden bursts of speed.
The size of these fish varies greatly, they can be found as small as seven inches long and as large as thirty-nine feet. The skin of the shark is composed on dermal denticles. This is not related to the scales that other fish have, but is more like a corset that is flexible and acts like an outer skeleton. The skin is very tough and has been used for sandpaper and leather in commercial industries.
Connective tissue hold the cartilage of this boneless fish. The lack of bones and a rib cage allow it to twist, bend, and move much more quickly than a regular fish. They also are able to control their movements when they are moving through the water.
Only a few sharks jump out of the water. These fish catch birds and other animals that are near the surface of the water. Some Makos have been known to jump into boats. Many of these beautiful creatures are on the endangered species list because of uncontrolled hunting and a disregard for the many lessons they can teach humans in the art of survival.
About the Author
In his studies of sharks one feature that has always fascinated Andries Joubert is shark migration.
Rating: Not yet rated
