Narwhal

Narwhals are mid-sized whales known for the long tusk that grows from their nose. The tusk, forming from a protruding canine tooth, appears primarily on males and can grow up to 10 feet in length over the course of an adult narwhal's life. In addition to helping the narwhal attract mates (much like a peacock's feathers), the tusk can serve as a weapon.

Like dolphins, narwhals communicate via clicks and whistles, and they use sound to navigate and hunt. They congregate in groups of five to 10, except in the summer when they gather in the hundreds. Adult narwhals are typically 13-18 feet long (not counting the tusk) and weigh 1,500-3,500 pounds.

The similarities between a narwhal's tusk and a unicorn's horn have led to the narwhals' nickname of "sea unicorns," but the narwhal's tusk is not made of the same highly sought material. Legends surrounding narwhals have nevertheless attributed magical characteristics to these remarkable tusks, such as neutralizing poison. Collectors and artisans also value the tusks as an elegant crafting material useful for carvings and other works of art.