The narwhal’s tusk is actually a large tooth

The unicorn of the sea, narwhals are known for the large tusk protruding from their heads. In fact, the narwhal’s spiral tusk can grow up to 10 feet in length, according to the World Wildlife Fund.

The narwhal’s tusk is actually a large tooth, and it contains about 10 million nerve endings, as further explained by the World Wildlife Fund. This means the tusk likely has some sensory capabilities.

Its name is derived from the Norse word “nar,” which means “corpse-like,” according to Whale Facts. With this in mind, the name narwhal means “corpse whale.” This may be in reference to the narwhal’s grey-white coloring, which sort of resembles a dead body. Yikes.