10 Fun Facts about Sharks


By Justin Kovach

Sharks make the news for all the wrong reasons, but there are many other points of interest about this majestic fish that deserve consideration. So let’s sink our teeth into some fun facts about this celebrated deep-sea predator:

  1. There are over 500 species of shark varying in size, shape, environment and diet. While some are small, others, like the whale shark, can grow up to 40 feet long.
  2. Sharks live in every part of the ocean, and some can survive in fresh water. One of the most interesting in appearance is the Mitsukurina Owstoni, or goblin shark, so called for its facial features. It is the oldest living species among lamniform sharks, dating back to about 125 million years ago. 
  3. The first sharks are believed to have evolved about 400-455 million years ago. But it may have been even longer ago because unlike other fish, sharks have a flexible cartilage skeleton that is rarely preserved the same way typical fish bones are. Although they are considered vertebrates, they have no bones. Their skeletons are made of cartilage, making them cartilaginous fish. 
  4. All sharks have several rows of teeth, which they lose regularly, only to be replaced by new ones. Shark teeth from millions of years ago have been preserved at the bottom of the ocean. Sandy sediment that covered the shark teeth protected them from oxygen and bacteria, allowing them to fossilize over the course of 10,000 years. 
  5. Sharks eat fish, crustaceans, mollusks, plankton, marine mammals, and even other sharks. Their strong sense of smell allows them to detect blood in the water miles away.
  6. Most sharks are cold-blooded. But some sharks, such as the great white shark, are warm-blooded, which enables them to grow and swim faster. But they need to eat up to 10 times more than their cold-blooded cousins. 
  7. Some etymologists believe the word shark derives from earlier German and Dutch words for a shifty character, while others suggest it comes from Xoc (pronounced "shoke"), which means “great fish” in the Mayan language of Yucatec.
  8. The largest known species was the megalodon, which grew longer than 50 feet. But you're safe from that behemoth, as it went extinct around 2.6 million years ago.
  9. The notion that sharks can’t develop cancer is a myth. They do, as we've known since at least 1908. Researchers in Australia found a tumor protruding from the mouth of a great white shark in 2013. 
  10. Humans perceive sharks as a threat, yet the fishing industry kills up to 100 million sharks a year just for their dorsal fins. The slaughtered far outnumber the few shark attacks that are reported each year. So even though they can be aggressive, remember that when you're swimming in the ocean, you’re swimming in their home. It is best to be not only cautious but also appreciative of this diverse and ancient species that is an integral part of a vast and magnificent ecosystem.  


  • What other interesting facts about sharks do you know?
  • What conservation efforts are being made on sharks’ behalf? Discuss their benefits or other measures that may be necessary to ensure their survival. 


  • Buoyancy
  • Etymology
  • Lamniform