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Sand shark

Sand sharks, also known as sand tiger sharks or ragged tooth sharks, are lamniform sharks of the family Odontaspididae (or sometimes - but incorrectly - referred to as Carchariidae). They are found worldwide in temperate and tropical waters, including on both sides of the Atlantic coast, but most notably in the Western Indian Ocean and in the Gulf of Maine.^{[citation needed]} There are four species in two genera. Sand sharks are the only known shark to surface for gulps of air. They store the air in their stomachs which allows them to float motionless in the water as they hunt for prey.

Deion

Sand sharks have a large second dorsal fin. They grow up to 3.9 metres (13 ft) in adult length.^[1] A Sand Shark can reach up to 250 pounds, which is quite light compared to other sharks. The body tends to be brown in color with dark markings in the upper half. They possess a rudimentary swim bladder^{[citation needed]} - a highly unusual feature in sharks - which enables them to have fine control over their buoyancy compared with other sharks. Their needle-like teeth are highly adapted for impaling fish, their main prey. Their teeth are long, narrow, and very sharp with smooth edges, with one and on occasion two small spurs, "denticles", on either side of the jaw.^[2]

Reproduction

Sand sharks only develop two embryos, one in each uterus. The strongest pups eat other embryos and any other unfertilized eggs in a process called "intrauterine cannibalism" before being born. They have a gestation period of about 9 to 12 months. A female Sand Shark becomes sexually mature when she reaches 2 meters long. At birth, Sand Sharks are already 1 meter long.^[3]

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