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"Alien Sharks of the Deep" Shark Week 2013
A frilled shark, a very old type species of shark, sometimes called a living fossil. Part of red gills are exposed to efficiently take oxygen from the water in the abyss containing much less oxygen than near the surface.

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'Alien Sharks of the Deep' Gets Weird

August 7, 2013

Discovery's new Shark Week special "Alien Sharks of the Deep" shines a light on the darkest corners of our oceans to reveal some truly strange sharks. Here are five of the creepiest fish you'll see this Shark Week. — Robert Chan, Yahoo! TV