Some fun shark facts include that they have no bones, they have skin like sandpaper, have extraordinary sensory skills and teeth that are constantly being replaced. Most sharks never stop swimming and some species give birth to live young, called pups.Continue Reading
Sharks have cartilage instead of bone, making their bodies lighter and more flexible. Cartilage is the same substance that humans have in their ears and noses. This gives the shark the capability to "turn on a dime" and swim fast at the same time when pursuing prey.
The sandpaper-like skin is made up of dermal denticles, a type of scale that's more like a tooth. Each denticle has a pulp cavity, dentine and an enamel surface and helps streamline the shark, reducing water friction. Some animals can be injured by brushing against the skin, which helps the shark incapacitate prey.
Sharks can sense a struggling fish in water from a distance of 500 meters, or 1,640 feet. They have a series of canals that reach from head to tail that are filled with sensory cells growing minute hairs. The hairs pick up the water vibrations. Sharks can also smell one drop of blood in one million drops of water.
Sharks teeth are often lost during hunting forays, but there are rows of teeth behind the main set in various stages of development. As a front tooth is lost, the next one back moves into position. Sharks must keep swimming in order to keep water flowing over their gills. One exception is the nurse shark, which usually stays still during the colder months and while sleeping.
Shark pups, whether live born or hatched out of egg sacks left on the ocean floor, instinctively know how to swim and hunt. When they are small, they are closer to the bottom of the food chain and are often preyed upon by other sharks. They are also born with voracious appetites, which help them grow faster.Learn more about Sharks