"Sharks are a large group of fish that have inhabited the oceans for over 400 million years, even before dinosaurs populated our planet. They belong to the superorder Selachimorpha, and modern sharks have specific characteristics like a cartilaginous skeleton, five or six pairs of gills and several rows of teeth." -sharks-world.com
From the Smithsonian's Ocean Portal:
The Many Species of Sharks
There are over 370 different species of sharks, from small and spunky to gigantic and docile.
Shark Senses from Discovery's Sharkopedia
"A shark's main missions in life are to eat and survive. But finding food in the ocean takes an arsenal of finely tuned senses, even some we don't have. Find out how sharks are hardwired to hunt their prey." sharkopedia.discovery.com
On Animal Planet's series "Fooled by Nature," we learn about the most famous teeth on Earth: shark teeth. Sharks have a massive bite, with rows of teeth. They even have teeth on the surface of their skin.
Words to Know
Cartilage strong connective tissue that supports the body and is softer and more flexible than bone
Denticles- The teeth-like scales that cover sharks’ skin which help them to swim quickly.
Dorsal Fin an unpaired fin on the back of a fish or whale, e.g., the tall triangular fin of a shark or killer whale.
Ecosystem a biological community of interacting organisms and their physical environment.
Electroreception a shark's "sixth" sense; electroreception is the ability to sense electrical signals/
Gill Slits any of a series of openings between the gill arches of a fish, through which water passes from the pharynx to the exterior, bathing the gills in the process.
Habitat The natural home or environment of an animal, plant, or other organism.
Plankton tiny plants and animals that float in the ocean
Pectoral Fin each of a pair of fins situated on either side just behind a fish's head, helping to control the direction of movement during locomotion. They correspond to the forelimbs of other vertebrates.
Predator an animal that naturally preys on others.
Pup a young shark.
Species a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding.
Temperate being of mild temperature: neither extremely hot nor extremely cold.
Shark Research Institute (SRI), a multi-disciplinary nonprofit scientific research organization, was created to sponsor and conduct research on sharks and promote their conservation. sharks.org
The Ocean Portal from the Smithsonian National Museum of Natural History offers in depth info and resources for educators. ocean.si.edu
Educator resources from Florida's official Natural History Museum located at the University of Florida. flmnh.ufl.edu
The Discovery Channel's interactive one stop shop for Shark information, videos and activities. sharkopedia.discovery.com