Pygmies of the Sea

posted: 04/11/12
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A spined pygmy shark, or a creepy finger puppet?
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Pygmy sharks, sometimes known as spined pygmy sharks, are some of the smallest sharks swimming the seas. Averaging about 8 inches (20 centimeters) long, these tiny, toothy little sharks hunt for prey at extreme depths — it's believed they might even plunge more than a mile (1.6 kilometers) underwater to catch a savory meal and stay out of the way of larger predators.

Pygmy sharks are special in another way, too. Besides being super small, they also exhibit a biological trait that is common among animal species, but much less common among sharks in particular. They're one of the few shark species to exhibit bioluminescence — they can make their own light. Although scientists don't know exactly why they have bellies that glow in the cold, dark ocean depths, some believe it could be a way for them to attract prey or mates. It may also be a crafty tool for foiling potential predators — something pygmy sharks' bigger kin don't always have to consider.

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