Title: BBC - Earth - The tusks of narwhals are actually teeth that are inside-out
Headings: The tusks of narwhals are actually teeth that are inside-out
The tusks of narwhals are actually teeth that are inside-out
Content: Doug Allan/NPL)
The narwhal's tusk was once passed off for exorbitant sums as unicorn horn. It is a mainly male feature, but occasionally female narwhals have one. There are also a few "double tuskers": males that have two tusks rather than one, for unknown reasons. A lot of people think this whale has teeth in its mouth, and it has none
Perhaps the most pervasive myth about the tusk is that narwhals use it to spear food. Anyone who believes this needs to think through the practicalities, says Kristin Westdal of The Pew Charitable Trusts' Oceans North Canada. Narwhal tusks can grow to lengths of 2-3m, and they eat relatively small prey like halibut, shrimp and squid. Spearing these animals would be really difficult, and even if a narwhal managed it, it would not have any other appendages long enough to retrieve the fish from its tusk. Many people also have the idea that narwhals chew their food. This is understandable, given that they belong to a group of animals known as " toothed whales ", but it's not true.