™™Scientific name: Class Chondrichthyes
Superorder Elasmobranchs
 | Size |
There are approximately 350 different kinds of sharks. The largest is the whale shark, which can reach lengths up to 45 feet long. One of the smallest species could be the midwater shark which reaches lengths up to 8 to 10 inches.
| What do they eat? |
What they eat depends on the kind of sharks. Some eat crustaceans, mollusks, or small fish. Others eat larger fish, squid, and octopus. Others may eat dolphins, seals, sea lions, penguins, other sharks, and whales. Some are even plankton eaters.
| Shark Highlights: |
Sharks are extraordinary predators. To find their food sharks use their sense of hearing and smell to locate prey (lunch). When they get closer to their prey the "lateral line" help them find the prey. The lateral line is a fluid filled canal that runs along the side of a shark's body. The movement of the small sensory hairs in the lateral line feel vibrations and movements in the water.Sharks have been around a long time - longer than dinosaurs. Fossil evidence shows sharks (relatives of today's sharks) existed 400 million years ago. The shark families that exist today were around at least 100 million years ago.
Sharks are found all over the world, even in some freshwater rivers. Depending on the species of shark, some have live birth, others hatch from an egg. Sharks don't stay with their young. As soon as the egg is laid or the pup is born the female leaves. (Leviathan Link: Shark Reproduction)
Some sharks travel with other sharks (in schools) others are solitary. This also depends on the species of shark.
Moving closer still, they use their eyes to track prey. It is thought that in clear water, some sharks may be able to see up to 50 feet away (15 meters).
When a shark gets right next to the food their "Ampullae of Lorenzini" helps them get the food right in their mouth. Ampullae of Lorenzini pick up electrical currents in the water. Anything alive gives off an electrical current.
No bones about it... Sharks do not have bones. That doesn't mean they do not have a skeleton, though. A shark's skeleton is made of cartilage (like in your ears and nose bridge).
Do sharks and dolphins fight? Find out...
What about shark reproduction?
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