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- Shark - Wikipedia
Sharks are a group of elasmobranch cartilaginous fishes characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head Modern sharks are classified within the division Selachii[1] and are the sister group to the Batomorphi (rays and skates)
- Shark | Attacks, Types, Facts | Britannica
Shark, any of numerous species of cartilaginous fishes that make up the order Selachii (class Chondrichthyes) Most species have a tough skin that is dull gray in color and roughened by toothlike scales
- Shark Species — Shark Research Institute
An annotated and illustrated catalogue of shark species known to date by Leonard J V Compagno, Ph D , the world’s foremost expert on sharks and Director of our Board of Trustees
- White Shark Information - California Department of Fish and Wildlife
White sharks, also called great white sharks (Carcharodon carcharias), are one of the ocean's primary predators, and fascinating creatures to many Yet white sharks remain one of the least understood of the sea's creatures, despite the enormous public and scientific interest in them
- Sharks, explained | National Geographic
Sharks can rouse fear and awe like no other creature in the sea Find out about the world's biggest and fastest sharks, how sharks reproduce, and how some species are at risk of extinction
- Sharks | Smithsonian Ocean
There are more than 500 species of sharks swimming in the world’s ocean Yet when most people think of these cartilaginous fish, a single image comes to mind: a large, sharp-toothed and scary beast That generalization does sharks a huge disservice, as they have far more variety than that
- Shark Facts | Fish | BBC Earth
Sharks are often characterised as vicious killers, but in reality, they’re a diverse and endangered group of creatures that add tremendous value to marine ecosystems Despite having a reputation as vicious, bloodthirsty predators, sharks are much more benign, varied and diverse than their portrayal in popular culture suggests
- Shark Resource Collection | National Marine Sanctuaries
Sharks, a species that has existed for more than 400 million years, exist throughout our world’s ocean with more than 450 species of shark in total Most sharks are apex predators and sit at the top of the food chain
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