Scientists have determined that there are approximately 465 species of sharks swimming in our oceans. As far as we know there could be more prowling the depths of the water that covers 71% of the earth. Sharks have been on earth far longer than humans have, around 400 million years to be exact. Since they’ve been on earth for so long they have had time to adapt better to their surroundings. The smallest shark scientists have identified is the Etmopterus perryi also known as the dwarf lanternshark. The maximum length of this shark is 8.3 inches. On the other hand, the largest species of sharks known to man is the Megaladon. It reached lengths of 70 feet and a weight of 100 tons. The lifespan of a shark also varies. Most sharks live around 20-30 years but the spiny dogfish has been known to live for 100 years. In captivity, however, a shark’s lifespan drastically decreases. For example, the whale sharks can live up to 100 years in their natural habitat while in captivity they would be lucky to even reach the age of 8.
|