Shark

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 and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark, a deep sea species that is only 17 centimetres in length, to the whale shark, the largest fish in the world, which reaches approximately 12 metres in length. Sharks are found in all seas and are common to depths up to 2,000 metres. They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and freshwater.

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Aussies, Drop That Fish! It May Be Endangered Shark.

First Confirmed ‘Night Shark’ In Puerto Rico Spotted

Researchers Sequence Genomes of Two Endangered Shark Species

Genomes of endangered great hammerhead and shortfin mako sharks reveal historic population declines. The findings may help develop more nuanced shark management strategies.

Massive graveyard of fossilized shark teeth found deep in the Indian Ocean

Female zebra shark opts for 'virgin birth' even when sharing a tank with healthy males

House Passes Legislation Banning The U.S. Shark Fin Trade

Scientists Discover Shark Graveyard In Australia

Accidental Shark Catches Have Been Dramatically Reduced By Electric Pulses

Swimming In Great White Shark Territory? You Might Want To Grab This.

202 Shark Week episodes found to be filled with junk science, misinformation and white male 'experts' named Mike

Study explores link between shark nose shape, size and sensitivity of smell

Lowest ever price! Save $130 on this Shark air purifier for Cyber Monday

International body likely to protect many shark and ray species

Groundbreaking CITES Vote Regarding Global Shark Conservation

U.S. Government Decides Against Adding Great Hammerhead Shark To Endangered Species List

A Loss Of Support For The Maldives Shark Sanctuary

Greenland Shark Finally Gets Protection

Shark Finning By One Of China’s Largest Fishing Fleets Is Worse Than We Thought

Shocking 439-Million-Year-Old “Shark” Forces Scientists To Rethink the Timeline of Evolution