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Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the Batoidea ( rays and kin).
Find out about the world's biggest and fastest sharks, how sharks reproduce, and how some species are at risk of extinction. Subscribe: http://bit.ly/NatGeoSubscribe #NationalGeographic #Sharks #...
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Like rays and skates, sharks fall into a subclass of fish called elasmobranchii. Species in this subclass have skeletons made from cartilage, not bone, and have five to seven gill slits on each side of their heads (most other fish have only one gill slit on each side), which they use to filter oxygen from the water. Whale sharks, the largest fish s...
Sharks are found in deep and shallow waters throughout the world’s oceans, with some migrating vast distances to breed and feed. Some species are solitary, while others hang out in groups to varying degrees. Lemon sharks, for example, have been foundto congregate in groups to socialize. Scientists are still trying to figure out how long sharks live...
People aren’t on a shark’s menu. Even though shark attacks have increased at a steady ratesince 1900—a result of better recording of attacks and a rising human population—they are still exceedingly rare: A beachgoer has only a one in 11.5 million chance of being bitten. Sharks bite people out of curiosity, to defend themselves from a perceived thre...
Sharks may not be a significant threat to us, but we are to them. Humans are responsible for drastic declines in shark populations. Overfishing is the biggest threat. An estimated 100 million sharks are killed each year, mostly to supply demand for an expensive Chinese dish called shark fin soup. Some fisheries allow the catch of whole sharks, like...
Learn about the world's oldest and most diverse fish, from their skeletons and teeth to their diets and migrations. Find out how sharks are threatened by overfishing, climate change, and human activities.
2 days ago · Learn about sharks, the cartilaginous fishes of predatory habit that have more than 400 living species. Find out their characteristics, habitats, diets, threats, and human interactions.
- Jeffrey Carrier
Learn about sharks, their diversity, importance and threats from overfishing, demand for fins and bycatch. Find out what WWF is doing to protect sharks and rays and how you can help.
Some common kinds of shark are the hammerhead shark, the great white shark, the tiger shark, and the mako shark. Most sharks are cold-blooded but some, like the great white shark and the mako shark are partially warm-blooded.
Learn about the largest predatory fish on Earth, its speed, teeth, camouflage, and reproduction. Find out how humans threaten this vulnerable species and what is being done to protect it.
