Narwhal

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What it is: The closest thing the planet has to a unicorn (albeit a swimming one), this medium-sized, speckled whale has a long, spiraling horn—technically a tooth—that can grow up to nine feet in length for males.

What’s strangest about it: Though no one knows exactly what the narwhal’s horn is for, it’s thought to play a part in mating rituals. Males have been spotted battling with their horns, as if fencing with swords (apparently to impress females); occasionally, narwhal skulls are found with other narwhals’ horns embedded in them.

Where to see it: In Arctic waters, especially off the eastern and western coasts of Greenland. The High Arctic Explorer and Spitsbergen & East Greenland cruises run by Mountain Travel Sobek (mtsobek.com) give narwhal fans the best chance of glimpsing the creatures, which swim in the icy clear water between floes and bergs.

The World's Strangest Animals

Narwhal

What it is: The closest thing the planet has to a unicorn (albeit a swimming one), this medium-sized, speckled whale has a long, spiraling horn—technically a tooth—that can grow up to nine feet in length for males.

What’s strangest about it: Though no one knows exactly what the narwhal’s horn is for, it’s thought to play a part in mating rituals. Males have been spotted battling with their horns, as if fencing with swords (apparently to impress females); occasionally, narwhal skulls are found with other narwhals’ horns embedded in them.

Where to see it: In Arctic waters, especially off the eastern and western coasts of Greenland. The High Arctic Explorer and Spitsbergen & East Greenland cruises run by Mountain Travel Sobek (mtsobek.com) give narwhal fans the best chance of glimpsing the creatures, which swim in the icy clear water between floes and bergs.

Getty Images/National Geographic Creative

The World's Strangest Animals

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