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Narwhal has the strangest tooth in the sea

5:00pm, May 4, 2014
narwhal illustration

TWISTING TOOTH  Most narwhals grow only one, the left tooth, and it always spirals to the left. Even in the rare cases where a right tusk emerges too, it also spirals to the left instead of having the mirror symmetry usual for mammal body parts. Narwhal tusks can grow to half the animal's body length.

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Sometimes called the unicorn of the sea, the male narwhal’s tusk is actually a tooth, and it grows directly through the whale’s upper lip instead of pushing the lip aside. It’s an exuberantly large version of a canine tooth that grows in a spiral; the only tooth known to do so. Otherwise narwhals are practically toothless, with only vestigial stubs that stop growing during development and rarely emerge into the mouth.

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