The narwhal tusk was considered to be one of the ocean’s greatest mysteries by researchers and seafaring enthusiasts until just a few years ago. Narwhals, which are medium-sized toothed whales that were first discovered in the mid-1700s, possess a large tusk that extends from a protruding canine tooth. Because they commonly dive to depths of up to 1,500 meters, narwhals are rarely seen, and because of the fact that they are often killed off by suffocation or starvation when the sea ice freezes over, narwhals have always been difficult to spot and study, most especially now that their current population of about 75,000 qualifies as near threatened.
The tusk is a characteristic of the male of the narwhal species. It is about 1.5 to 3 meters in length, straight and narrower as it spirals toward the tip. Because of the resemblance that the narwhal tusk has to a unicorn’s horn, narwhals were nicknamed the “unicorns of the ocean.” The tusk projects from the left side of the male narwhal’s upper jaw, and it continues growing throughout the specimen’s life. Although most females of the species don’t grow tusks, about 15% of them have been estimated to possess a similar growth, that is however, much smaller and with a less pronounced spiral than that of a male narwhal.
Before a recent study has managed to shed light on the actual purpose of the tusk, people have come up with a variety of myths and stories about its function. Some have ventured a guess that it might be an ice pick that the narwhals may have evolved in order to smash through the ice when they are trapped. Certain researchers have also pointed out that it might be an acoustic probe used by the animal to communicate or sense disturbances in the water from a long distance away. Until recently, however, scientists have been unable to prove any of these claims, nor did they have the knowledge and equipment necessary to study the matter further.
Drone footage of narwhals has revealed that the tusk is actually a weapon that the narwhals use in a more unusual fashion. The tooth that spirals out of the left side of the narwhal’s jaw are long and sharp enough to allow the species to use it for hunting purposes. However, further research also suggests that the tusk is used to detect chemical changes in the water. Studies conducted on live narwhals and the detailed examination of the tusks show that the animals can use them to actually taste or detect food and even to find females that are ready to mate.